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Hindawi Publishing CorporationActive and Passive Electronic ComponentsVolume 2013 Article ID 720191 7 pageshttpdxdoiorg1011552013720191

Research ArticleNoise Performance of Heterojunction DDR MITATT DevicesBased on Si sim Si

1minus119909Ge

119909at W-Band

Suranjana Banerjee1 Aritra Acharyya2 and J P Banerjee2

1 Academy of Technology West Bengal University of Technology Adisaptagram Hooghly West Bengal 712121 India2 Institute of Radio Physics and Electronics University of Calcutta 92 APC Road Kolkata West Bengal 700009 India

Correspondence should be addressed to Aritra Acharyya ari besuyahoocoin

Received 24 February 2013 Accepted 5 April 2013

Academic Editor Gerard Ghibaudo

Copyright copy 2013 Suranjana Banerjee et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

Noise performance of different structures of Si sim Si1minus119909

Ge119909anisotype heterojunction double-drift region (DDR) mixed tunneling

and avalanche transit time (MITATT) devices has been studied The devices are designed for operation at millimeter-wave W-band frequencies A simulation model has been developed to study the noise spectral density and noise measure of the deviceTwo different mole fractions 119909 = 01 and 119909 = 03 of Ge and corresponding four types of device structure are considered forthe simulation The results show that the 119899 minus Si

07Ge03

sim 119875-Si heterojunction DDR structure of MITATT device excels all otherstructures as regards noise spectral density (082times10

minus16 V2 sec) and noise measure (3309 dB) as well as millimeter-wave propertiessuch as DC-to-RF conversion efficiency (2015) and CW power output (77329mW)

1 Introduction

Impact avalanche transit time (IMPATT) devices are noisydevices having an average noise level of 30ndash40 dB [1ndash4] Thenoise in IMPATT devices arises mainly from random natureof carrier generation by impact ionization and avalanchemultiplication phenomena The intrinsic avalanche noise inIMPATT device depends mainly on the carrier ionizationrates in the base semiconductor material [5] The group IV-IV compound semiconductor Si

1minus119909Ge119909has been used as an

important base material for both optoelectronic and micro-electronic devices [6ndash9] Si

1minus119909Ge119909is a bandgap engineered

material whose material properties depend on the Ge molefraction (119909) [10]

Mixed tunneling avalanche transit time (MITATT) deviceis an important member of avalanche transit time (ATT)device family operating at higher millimeter-wave frequen-cies [11ndash23] In 1958 W T Read [11] in his very early paperpredicted that band-to-band tunneling phenomenon mightlimit the DC-to-RF conversion efficiency of the IMPATTdiodes at high frequencies Kwok and Haddad [12] reportedthe effect of tunneling on the negative conductance of thedeviceThey considered that instantaneous carrier generation

process through tunneling is equivalent to that of a field-dependent carrier source This concept gave birth to newmodes of IMPATT device namelyMITATT and tunnel tran-sit time (TUNNETT) modes Nishizawa et al [13] describedthe design and principle of the pulse oscillation character-istics of GaAs TUNNETT diodes Elta and Haddad [14 15]analyzed the high frequency performance of IMPATT diodeby using a modified Read-type equation and consideringdead space correction for impact ionization for the chargecarriers They proposed that the above mentioned threedifferent modes (pure IMPATT MITATT and TUNNETTmodes) of operation of IMPATT depend on the widthof avalanche region Luy and Kuehnf [16] found that thedevice efficiency decreases due to tunnel generated carriersA generalized computer simulation method for MITATTmode based on the model proposed by Roy et al [17 18]was later reported [19] Elta [20] and Kane [21] showedthat the performance of IMPATT devices deteriorates dueto tunneling-induced phase distortion Eisele and Haddad[22] also carried out experimental work on TUNNETTmode operation of IMPATT diodes grown on diamondheat sink They reported highest RF conversion efficiencyof TUNNETT devices According to [23] special designs of

2 Active and Passive Electronic Components

119899+

Si

(Si1minus119909Ge119909)

119899

Si

(Si) (Si)(Si1minus119909Ge119909)

119901+

119901

Si1minus119909Ge119909 Si1minus119909Ge119909

119909 = 0 119909119860

119909119860

1 119909119895 1199091198602 119882

119882119899119882119901

Figure 1 One-dimensional schematics of the Si sim Si1minus119909

Ge119909aniso-

type heterojunction DDRMITATT devices

MITATT devices can provide higher efficiency higher outputpower and lower noise as compared to normal IMPATTdiodes The effect of tunneling on the high frequency prop-erties of DDR Si IMPATTs operating at millimeter-wave andterahertz frequencies was studied and reported by Acharyyaet al in their earlier paper [24 25] which showed that thecritical background doping concentration and operating fre-quency above which tunneling effect becomes predominantare 50 times 1023mminus3 and 260GHz respectivelyThemillimeter-wave performance of IMPATTs operating in MITATT modewas studied by Acharyya et al from the shift of avalanchetransit time (ATT) phase delay and reported in [26] Thereported results show that with increasing frequency the shiftof ATT phase delay increases which explains the physicalreason behind the deterioration of millimeter-wave perfor-mance of the device at higher frequencies Since tunneling isa noiseless phenomenon it is expected that the noise level inMITATTs will be lower than that in IMPATTs Furthermoreit is reported [27] that heterojunction IMPATTs have lowernoise level than their homojunction counterparts All thesefacts have inspired the authors to study the noise performanceof four types of Si sim Si

1minus119909Ge119909anisotype heterojunction

DDR structures of MITATT devices at W band In this studyonly two different mole fractions of Ge 119909 = 01 and 119909 =

03 are considered The performance of different structuresof heterojunction DDR MITATTs is compared with theirhomojunction counterpart based on Si operating at the samefrequency band

2 Simulation Method to Studythe Noise Properties

One-dimensional model of reverse biased Si sim Si1minus119909

Ge119909

DDR MITATT device shown in Figure 1 is considered fornoise analysis The DC electric field and current densityprofiles in the depletion layer of the device are obtainedfrom simultaneous numerical solution of fundamental deviceequations that is Poissonrsquos equation combined carrier conti-nuity equation in the steady state current density equationsand mobile space charge equation subject to appropriateboundary conditions as discussed in detail in the earlierpapers by the authors of [24ndash26] A double-iterative simula-tion method described elsewhere [17] is used to solve theseequations and to obtain the electric field and current densityprofiles The boundary conditions for the electric field at the

depletion layer edges that is at 119909 = 0 and 119909 = 119882 are givenby

120585 (0) = 0 120585 (119882) = 0 (1)

Similarly the boundary conditions for normalized currentdensity 119875(119909) = (119869

119901(119909) minus 119869

119899(119909))119869

0(where the total current

density 1198690= 119869119899(119909) + 119869

119901(119909) where 119869

119899(119909) and 119869

119901(119909) are the

electron and hole current densities respectively at the spacepoint 119909) at the depletion layer edges are given by

119875 (0) = (2

119872119901(0)

minus 1) 119875 (119882) = (1 minus2

119872119899(119882)

)

(2)

where 119872119899(119882) and 119872

119901(0) are respectively the electron and

hole multiplication factors at the depletion layer edges whosevalues are of the order of 106 under dark or unilluminatedcondition of the device

The magnitude of peak field at the junction (120585119901) break-

down voltage (119881119861) the widths of avalanche and drift zones

(119909119860and119909119863 where119909

119863=119889119899+119889119901) and the voltage drops across

these zones (119881119860 119881119863= 119881119861

minus 119881119860) are obtained from double-

iterative DC simulation program These values are fed backas input parameters in the small-signal simulation programto obtain the admittance properties of the device such asavalanche resonance frequency (119891

119886) optimum frequency

(119891119901) negative conductance (119866(120596)) and corresponding sus-

ceptance (119861(120596)) as functions of frequency Two second-order differential equations are framed by resolving the diodeimpedance 119885(119909 120596) into its real part 119877(119909 120596) and imaginarypart 119883(119909 120596) [18 19 24 25 28ndash31] Here 119885(119909 120596) = 119877(119909 120596) +

119895119883(119909 120596) where 119877(119909 120596) and 119883(119909 120596) are respectively thenegative specific resistance and specific reactance at the spacepoint 119909 for angular frequency of 120596 (frequency 119891 = 2120587120596)A double-iterative simulation over the initial choice of thevalues of 119877 and 119883 described in details in [18] is used to solvesimultaneously the two above said second order differentialequations subject to appropriate boundary conditions at thedepletion layer edges The spatial profiles of negative specificresistance and specific reactance (ie 119877(119909 120596) versus 119909 and119883(119909 120596) versus 119909) for a particular frequency are obtainedfrom the above solution within the depletion layer of thedevice The device negative resistance (119885

119877(120596)) and reactance

(119885119883(120596)) are obtained from the numerical integration of the

119877(119909 120596) and119883(119909 120596) profiles over the space-charge layerwidth(119882) Thus

119885119877(120596) = int

119882

0

119877 (119909 120596) 119889119909 119885119883(120596) = int

119882

0

119883 (119909 120596) 119889119909

(3)

The impedance of the device is given by 119885119863(120596) = 119885

119877(120596) +

119895119885119883(120596) and the device admittance is 119884

119863(120596) = 1119885

119863(120596) =

119866(120596) + 119895 119861(120596) The negative conductance and corresponding

Active and Passive Electronic Components 3

susceptance at different frequencies are computed from thefollowing expressions

|119866 (120596)| =119885119877(120596)

(119885119877(120596)2+ 119885119883(120596)2)

|119861 (120596)| =minus119885119883(120596)

(119885119877(120596)2+ 119885119883(120596)2)

(4)

The random nature of the impact ionization process isthe main source of noise in avalanche transit time (ATT)devices This random impact ionization process gives rise tofluctuations in the DC current and DC electric field whichappear as small-signal components to their DC values evenin the absence of voltage variation across the device Opencircuit condition without any variation of applied voltageis considered for the noise analysis of IMPATTMITATTdevice Starting from the small-signal AC field due to noise119890(119909 119909

1015840) = 119890119903(119909 1199091015840) + 119895 119890

119894(119909 1199091015840) two second-order differential

equations are framed corresponding to the real (119890119903(119909 1199091015840))

and imaginary (119890119894(119909 1199091015840)) parts of the noise electric field

119890(119909 1199091015840)This field is assumed to be due to a noise source 120574(1199091015840)

located at space point 1199091015840 within the depletion region of the

device [32ndash34] The numerical solution of two simultaneousdifferential equations involving the real and imaginary partsof noise electric field 119890(119909 119909

1015840) is carried out by using a

double-iterative technique and Runge-Kutta method subjectto the satisfaction of appropriate boundary conditions at thedepletion layer edges [32ndash34] The noise source 120574(119909

1015840) is first

considered to be located at one edge of the depletion regionThe noise source is then shifted to the next space point andthe procedure is repeated until the entire depletion region iscovered and the other edge of the depletion layer is reachedNumerical integration of noise electric field 119890(119909 119909

1015840) over the

entire depletion layer provides the terminal voltage 119881119879(1199091015840)

produced by noise source that is

119881119879(1199091015840) = int

119882

0

119890 (119909 1199091015840) 119889119909 (5)

The transfer impedance of the device is defined as

119885119879(1199091015840) =

119881119879(1199091015840)

119868119873

(1199091015840) (6)

where 119868119873(1199091015840) is the average current generated in the interval

1198891199091015840 due to 120574(119909

1015840) located at 1199091015840 Themean-square noise voltage

is obtained from

⟨V2

119899⟩ = 2119902

2sdot 119889119891 sdot 119860int

10038161003816100381610038161003816119885119879(1199091015840)10038161003816100381610038161003816

2

120574 (1199091015840) 1198891199091015840 (7)

Mean-square noise voltage per bandwidth is called noisespectral density (⟨V2

119899⟩119889119891V2 sec) The noise performance of

the device can be known from a parameter called the noisemeasure (NM) defined as

NM =⟨V2119899⟩119889119891

4119870119861119879 (minus119885

119877minus 119877119878) (8)

where119870119861is the Boltzmann constant (119870

119861= 138 times 10minus23 J Kminus1)

119879 is the absolute temperature 119885119877is the device negative

resistance and 119877119878is the positive parasitic series resistance

associated with the device

3 Material Parameters and Design

The realistic field dependence of ionization rates (120572119899 120572119901) and

drift velocities (V119899 V119901) of Si and Si

1minus119909Ge119909(119909 = 01 and 119909 =

03) at realistic junction temperature of 500K are taken fromthe recently published experimental reports [35ndash40] Othermaterial parameters of Si and Si

1minus119909Ge119909(119909 = 01 and 119909 = 03)

such as intrinsic carrier concentration (119899119894) effective density

of states of conduction and valance bands (119873119888119873V) diffusion

coefficients (119863119899119863119901)mobilities (120583

119899120583119901) and diffusion lengths

(119871119899 119871119901) of charge carriers and permittivity (120576

119904) are taken

from the published data given in [10] The active layer widths(119882119899119882119901) and doping concentrations (119873

119863119873119860) of all different

structures of MITATTs under consideration are designedfollowing a width modulated design method suggested forMITATTdevices in [23] for operation at 94GHz atmosphericwindow frequencyThe doping concentrations of the 119899

+- and119901+-layers (119873

119899+ 119873119901+) are taken to be in the order of 1025

for W-band operation The designed doping and structuralparameters are listed in Table 1

4 Results and Discussion

The authors have used a double-iterative simulation method[18 19 24 25 28ndash31] to study the static and high-frequencyproperties of homojunction (N-Si sim 119875-Si) and heterojunc-tion (119873-Si sim 119901-Si

09Ge01 N-Si sim 119901-Si

07Ge03 n-Si09Ge01

sim

119875-Si and n-Si07Ge03

sim 119875-Si) DDR IMPATTs operatingat 94GHz atmospheric window Peak tunneling generationrate (119902119866Tp) peak avalanche generation rate (119902119866Ap) andratio of 119866Tp to 119866Ap (119866Tp119866Ap ()) of all the devices underconsideration are listed in Table 2 The ratio 119866Tp119866Ap ()is very high (3169) in Si homojunction DDR IMPATTThus the phase distortion associated with tunneling resultsin deterioration of RF performance of the Si homojunctiondevice and the device operates in MITATT mode But thesame (119866Tp119866Ap ()) is very small around 006ndash029 inthe Si sim Si

1minus119909Ge119909heterojunction DDRs which indicates

that those devices operate in pure IMPATT mode (withoutconsiderable amount of band-to-band tunneling) at 94GHz

The simulated DC parameters such as peak electricfield (120585

119901) breakdown voltage (119881

119861) avalanche voltage (119881

119860)

avalanche layer width (119909119860) ratio of avalanche layer width to

total depletion layer width (119909119860119882 () whereW =119882

119899+119882119901)

and DC-to-RF conversion efficiency (120578) of all the devices atthe respective bias current densities (119869

0) are given in Table 3

Figure 2 shows the electric field profiles of those devices Itis evident from Figure 2 and Table 3 that the heterojunctionDDRs require lower field at breakdown as compared to theirSi homojunction counterpart Breakdown voltage (119881

119861) is

obtained by numerical integration of electric field profile overthe depletion layer width (ie from 119909 = 0 to 119909 = 119882)The simulated values of breakdown voltage of heterojunction


Table 1 Design parameters

Structureslowast 119882119899(120583m) 119882

119901(120583m) 119873

119863(times1023 mminus3) 119873

119860(times1023 mminus3) 119873

119899+ (times1025 mminus3) 119873

119901+ (times1025 mminus3) 119863

119895(120583m)dagger

NSPS 040 038 120 125 50 27 350NSpSG1 034 032 085 085 50 27 350NSpSG2 034 030 085 100 50 27 350nSGPS1 032 032 078 090 50 27 350nSGPS2 034 032 085 090 50 27 350lowastNSPS119873-Si sim 119875-Si homojunction DDRMITATTlowastNSpSG1119873-Si sim 119901-Si09Ge01 anisotype heterojunction DDRMITATTlowastNSpSG2119873-Si sim 119901-Si07Ge03 anisotype heterojunction DDRMITATTlowastnSGPS1 119899-Si09Ge01 sim 119875-Si anisotype heterojunction DDRMITATTlowastnSGPS2 119899-Si07Ge03 sim 119875-Si anisotype heterojunction DDRMITATTdagger119863119895 is the diameter of the p-n junction

Table 2 Values of 119902119866Tp 119902119866Ap and 119866Tp119866Ap

Parameters NSPS NSpSG1 NSpSG2 nSGPS1 nSGPS2119902119866Tp (times10

12 mminus3 secminus1) 55287 63498 36309 38271 14560q119866Ap (times10

15 mminus3 secminus1) 17441 45615 35989 13303 22810119866Tp119866Ap () 3169 014 010 029 006

Table 3 Millimeter-wave and noise properties

Parameters NSPS NSpSG1 NSpSG2 nSGPS1 nSGPS21198690(times108 Amminus2) 28 30 32 33 36

120585119901(times107 Vmminus1) 60125 36760 35666 35534 33656

119881119861(V) 2389 1289 1181 1140 1108

119881119860(V) 1634 667 606 437 407

119909119860(120583m) 0354 0210 0204 0166 0162

119909119860119882 () 4539 3182 3186 2594 2455

120578 () 1006 1536 1549 1964 2015119891119901(GHz) 106 94 96 95 94

119866119901(times107 Smminus2) 46593 83760 10594 10441 11790

119861119901(times107 Smminus2) 17320 12252 90710 12102 42031

119876119901(= minus119861

119901119866119901) 372 146 086 116 036

119885119877(times10minus9Ωm2) 14484 38026 54463 40869 75254

119875RF (mW) 64744 57147 56322 71086 77329⟨V119899

2⟩119889119891

(times10minus16 V2 sec) 3951 375 185 139 082

NM (dB) 4000 3742 3654 3427 3309

devices are lower than that of homojunction device Againthe avalanche voltage drop can be obtained from numericalintegration of the electric field profiles over the avalancheregion (ie from 119909 = 119909

1198601to 119909 = 119909

1198602)The avalanche voltages

of heterojunction MITATTs are found to be smaller thanthat of homojunction device Narrower avalanche widths ofheterojunctionMITATTs indicate sharper growth of normal-ized current density profiles (119875(119909) versus 119909) The sharperthe growth of 119875(119909) profile the narrower the avalanche zoneThis leads to higher DC-to-RF conversion efficiency (120578) ofheterojunction devices as compared to their homojunctioncounterpart based on Si [41] Table 3 further shows that this

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

0

1

2

3

4

5

6

7times10

7

minus4 minus3 minus2 minus1 0 1 2 3 4times10

minus7

119899-side 119901-side

Junction

Position (m)

Elec

tric

fiel

d (V

mminus1)

Figure 2 Electric field profiles of the DDRMITATT devices

efficiency is the highest in n-Si07Ge03

sim 119875-Si heterojunctionDDR device (2015) of all other types of DDRs

The admittance characteristics of the devices underconsideration are shown in Figure 3 Table 3 shows thatmagnitude of the peak negative conductance (119866

119901) and neg-

ative resistance (119885119877) are higher for heterojunction MITATTs

as compared to those for Si homojunction counterpartIt may be noted that the above parameters (119866

119901 119885119877) are

maximum for n-Si07Ge03

sim 119875-Si heterojunction structure(nSGPS2) Also power output (119875RF) from that particularstructure (nSGPS2) is the highest (77329mW) as comparedto that from all other structures The lowest value of119876-factor(119876119901

= minus119861119901119866119901

=036) in that structure (nSGPS2) indicatesgrowth rate and stability of IMPATT oscillation The spatialvariations of negative resistivity of all structures of MITATTdevices are shown in Figure 4 All these negative resistivityprofiles exhibit two peaks in the two drift regions with aminimum in the avalanche regionThemagnitude of negativeresistivity peaks in both the drift layers is the highest in thatstructure (nSGPS2) compared to those of other structures

Furthermore it is interesting to observe fromTable 3 thatthough the breakdown voltage (119881

119861) of n-Si

09Ge01

sim 119875-Si and


minus12 minus11 minus10 minus9 minus8 minus7 minus6 minus5 minus4 minus3

times107

0

05

1

15

2

25times10

8

Conductance (S mminus2)

Susc

epta

nce (

S mminus2)

85GHz94GHz

94GHz

110GHz

110GHz

110GHz 110GHz106GHz

120GHz

85GHz

85GHz 85GHz80GHz95GHz

96GHz

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

Figure 3 Admittance characteristics of the DDRMITATT devices


minus7

15

10

5

0

minus5

minus10

minus15

minus20

minus25

times10minus3

Position (m)

Resis

tivity

(Ohm

middotm)

119901-side119899-sideJunction

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

Figure 4 Negative resistivity profiles of the DDRMITATT devices

n-Si07Ge03

sim 119875-Si heterojunctionDDRs is almost half of thatof Si homojunction DDR due to much smaller breakdownfield in Si

1minus119909Ge119909than that of Si [10 37ndash39] the RF power

output (119875RF = 120578 times 119881119861

times 1198690times 119860119895) which is proportional to

both the breakdown voltage (119881119861) and DC-to-RF conversion

efficiency (120578) of those heterojunction devices is higher ascompared to that of their homojunction counterpart dueto much larger DC-to-RF conversion efficiency (120578) of thoseabove said heterojunction devices

Figures 5 and 6 show respectively the simulated noisespectral densities (⟨V2

119899⟩119889119891) and noisemeasures (NM) against

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

109

1010

1011

1012

10minus19

10minus18

10minus17

10minus16

10minus15

10minus14

Frequency (Hz)

Noi

se sp

ectr

al d

ensit

y (V

2s)

Figure 5 Variations of noise spectral densities (⟨V2119899⟩119889119891 V2 sec) of

DDRMITATT devices with frequency

frequency of Si sim Si1minus119909

Ge119909heterojunction and Si homojunc-

tion DDR MITATT devices It is observed that both NSDand NM are minimum (082 times 10minus16 V2 sec and 3309 dB) inn-Si07Ge03

sim 119875-Si heterojunction DDR MITATT device at94GHzTheminimumnoise level in that particular structureis due to suppression of noisy impact ionization phenomenain the narrowest avalanche zone

The simulation results presented in this paper arecross checked with the previously reported experimentallyobtained results to validate the simulation scheme adoptedby the authors Luy et al [42] experimentally obtained CWpower output of 600mW at 94GHz with 67 efficiency inSi homojunction flat DDR in 1987 Latter Dalle et al [43]measured CW power output of about 500mW at 94GHzwith 80 conversion efficiency in 1990 These experimentalresults are in close agreement with the simulation results pre-sented in this paper for Si homojunction flat DDR (Table 3)The slight discrepancy in the simulated and experimentallyreported values RF power output and DC-to-RF conversionefficiency may be due to the slight difference in the designparameters andDC bias current densityThe first experimen-tal results on SiSi

1minus119909Ge119909heterostructure mixed tunneling

avalanche transit time (MITATT) diodes were reported byLuy et al [44] in 1988 They obtained 25mW of RF poweroutput with 13 of conversion efficiency at 103GHz But theyused Si

04Ge06

alloy to fabricate SiSi1minus119909

Ge119909heterostructure

Due to this fact and also due to lack of optimization oftheir design they obtained such lower power output andlower efficiency but the simulation results presented in thispaper with optimized design of the device predicting the factthat the SiSi

1minus119909Ge119909heterojunction DDRs especially the 119899119875

Si07Ge03Si heterojunction DDRs are capable of delivering


85 90 95 100 105 110 115 120 125 130 13510

20

30

40

50

60

70

Frequency (Hz)

Noi

se m

easu

re (d

B)

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

Figure 6 Noise measures (NM) versus frequency curves of DDRMITATT devices

much larger power with much larger conversion efficiencyas compared to the experimentally obtained values Thus thesuitable choice of Ge mole fraction (119909) of Si

1minus119909Ge119909 device

structure and proper optimization in design of the device areessential for getting expected RF power output

5 Conclusions

In this paper the authors have made an attempt to studythe millimeter-wave and noise properties of different struc-tures of SisimSi

1minus119909Ge119909anisotype heterojunctionDDRMITATT

devices This simulation study clearly indicates that the n-Si07Ge03

sim 119875-Si heterojunction MITATT is the most suit-able structure for generation of high RF power with highconversion efficiency and low noise measure The results areextremely encouraging for the experimentalists to fabricatethe n-Si

07Ge03

sim 119875-Si heterojunctionMITATTs for millime-ter-wave applications

References

[1] M E Hines ldquoNoise theory for the Read type avalanche dioderdquoIEEE Transactions on Electron Devices vol 13 no 1 pp 158ndash1631966

[2] H K Gummel and J L Blue ldquoA small-signal theory ofavalanche noise in IMPATT diodesrdquo IEEE Transactions onElectron Devices vol 14 pp 569ndash580 1967

[3] H A Haus H Statz and R A Pucel ldquoOptimum noise measureof IMPATT diodesrdquo IEEE Transactions on Microwave Theoryand Techniques vol 19 no 10 pp 801ndash813 1971

[4] R L Kuvas ldquoNoise in IMPATT diodes Intrinsic propertiesrdquoIEEE Transactions on Electron Devices vol 19 no 2 pp 220ndash233 1972

[5] J Banerjee K Roy and M Mitra ldquoEffect of negative resistancein the noise behavior of Ka-Band IMPATT diodesrdquo Interna-tional Journal of Engineering Science and Technology vol 4 no7 pp 3584ndash3691 2012

[6] Z Pei C S Liang L S Lai et al ldquoA high-performance SiGe-Simultiple-quantum-well heterojunction phototransistorrdquo IEEEElectron Device Letters vol 24 no 10 pp 643ndash645 2003

[7] A Acharyya and J P Banerjee ldquoA comparative study on theeffect of optical illumination on Si

1minus119909Ge119909and Si based DDR

IMPATT diodes at W-bandrdquo Iranian Journal of Electronics andElectrical Engineering vol 7 no 3 pp 179ndash189 2011

[8] A Acharyya and J P Banerjee ldquoA comparative study on theeffects of tunneling on W-band Si and Si

1minus119909Ge119909based double-

drift IMPATT devicesrdquo in IEEE International Conference onElectronics Computer Technology Kanyakumari India April2012

[9] A Acharyya and J P Banerjee ldquoStudies on anisotype SiSi1minus119909

Ge119909heterojunction DDR IMPATTs efficient millimeter-

wave sources at 94GHz windowrdquo IETE Journal of Research vol59 no 3 pp 1ndash9 2013

[10] ldquoElectronic Archive New Semiconductor Materials Charac-teristics and Propertiesrdquo 2012 httpwwwiofferuSVANSMSemicond

[11] W Shockley ldquoNegative resistance arising from transit time insemiconductor diodesrdquo Bell System Technical Journal vol 33pp 799ndash826 1954

[12] S P Kwok and G I Hadded ldquoEffects of tunnelling on anIMPATToscillatorrdquo Journal of Applied Physics vol 43 pp 3824ndash3860 1972

[13] J Nishizawa K Motoya and Y Okuno ldquoGaAs TUNNETdiodesrdquo IEEE Transactions on Microwave Theory and Tech-niques vol 26 no 12 pp 1029ndash1035 1978

[14] E M Elta and G I Haddad ldquoHigh frequency limitationsof IMPATT MITATT and TUNNETT mode devicesrdquo IEEETransactions on Microwave Theory and Techniques vol 27 no5 pp 442ndash449 1979

[15] E M Elta and G I Hadded ldquoMixed tunnelling and avalanchemechanism in p-n junctions and their effects on microwavetransit-time devicesrdquo IEEE Transactions on Electron Devicesvol 25 no 6 pp 694ndash702 1978

[16] J F Luy and R Kuehnf ldquoTunneling-assisted IMPATT opera-tionrdquo IEEE Transactions on Electron Devices vol 36 no 3 pp589ndash595 1989

[17] S K Roy M Sridharan R Ghosh and B B Pal ldquoComputermethod for the dc field and carrier current profiles in theIMPATT device starting from the field extremum in the deple-tion layerrdquo in Proceedings of the 1st Conference on NumericalAnalysis of Semiconductor Devices (NASECODE I rsquo79) J HMiller Ed pp 266ndash274 Dublin Ireland 1979

[18] S K Roy J P Banerjee and S P Pati ldquoA Computer analysisof the distribution of high frequency negative resistance inthe depletion layer of IMPATT Diodesrdquo in Proceedings of the4th Conference on Numerical Analysis of Semiconductor Devices(NASECODE IV rsquo85) pp 494ndash500 Dublin Ireland 1985

[19] G N Dash and S P Pati ldquoA generalized simulation methodfor MITATT-mode operation and studies on the influence oftunnel current on IMPATT propertiesrdquo Semiconductor Scienceand Technology vol 7 no 2 pp 222ndash230 1992


[20] M E Elta The effect of mixed tunneling and avalanche break-down on microwave transit-time diodes [PhDdissertation]Electron Physics Laboratory University of Michigan AnnArbor Mich USA 1978

[21] E O Kane ldquoTheory of tunnelingrdquo Journal of Applied Physicsvol 32 pp 83ndash91 1961

[22] H Eisele and G I Haddad ldquoGaAs TUNNETT diodes ondiamond heat sink for 100GHz and aboverdquo IEEE Transactionson MicrowaveTheory and Techniques vol 43 no 1 pp 210ndash2131995

[23] G N Dash ldquoA new design approach for MITATT and TUN-NETT mode devicesrdquo Solid-State Electronics vol 38 no 7 pp1381ndash1385 1995

[24] A Acharyya M Mukherjee and J P Banerjee ldquoEffects of tun-nelling current on mm-wave IMPATT devicesrdquo InternationalJournal of Electronics In press

[25] A Acharyya M Mukherjee and J P Banerjee ldquoInfluence oftunnel current on DC and dynamic properties of silicon basedterahertz IMPATT sourcerdquo Terahertz Science and Technologyvol 4 no 1 pp 26ndash41 2011

[26] A Acharyya M Mukherjee and J P Banerjee ldquoStudies onthe millimeter-wave performance of MITATTs from avalanchetransit time phase delayrdquo in Proceedings of the IEEE AppliedElectromagnetics Conference pp 1ndash4 Kolkata India December2011

[27] S R Pattanaik J K Mishra and G N Dash ldquoA new mm-waveGaAssimGa

052In048

PHeterojunction IMPATTdioderdquo IETE Jour-nal of Research vol 57 no 4 pp 351ndash356 2011

[28] A Acharyya and J P Banerjee ldquoProspects of IMPATT devicesbased on wide bandgap semiconductors as potential terahertzsourcesrdquo Applied Nanoscience 2012

[29] A Acharyya and J P Banerjee ldquoPotentiality of IMPATT devicesas terahertz source an avalanche response time based approachto determine the upper cut-off frequency limitsrdquo IETE Journalof Research vol 59 no 2 pp 1ndash10 2013

[30] A Acharyya S Banerjee and J P Banerjee ldquoOptical controlof millimeter-wave lateral double-drift region silicon IMPATTdevicerdquo Radioengineering vol 21 no 4 pp 1208ndash1217 2012

[31] A Acharyya and J P Banerjee ldquoAnalysis of photo-irradiateddouble-drift region silicon impact avalanche transit timedevices in the millimeter-wave and terahertz regimerdquo TerahertzScience and Technology vol 5 no 2 pp 97ndash113 2012

[32] G N Dash J K Mishra and A K Panda ldquoNoise in mixedtunneling avalanche transit time (MITATT) diodesrdquo Solid-StateElectronics vol 39 no 10 pp 1473ndash1479 1996

[33] A Acharyya M Mukherjee and J P Banerjee ldquoNoisein millimeter-wave mixed tunneling avalanche transit timediodesrdquo Archives of Applied Science Research vol 3 no 1 pp250ndash266 2011

[34] A Acharyya M Mukherjee and J P Banerjee ldquoNoise per-formance of millimeter-wave silicon based mixed tunnelingavalanche transit time (MITATT) dioderdquo International Journalof Electrical and Electronics Engineering vol 4 no 8 pp 577ndash584 2010

[35] W N Grant ldquoElectron and hole ionization rates in epitaxialSiliconrdquo Solid-State Electronics vol 16 no 10 pp 1189ndash12031973

[36] C Canali G Ottaviani and A Alberigi Quaranta ldquoDriftvelocity of electrons and holes and associated anisotropic effectsin siliconrdquo Journal of Physics and Chemistry of Solids vol 32 no8 pp 1707ndash1720 1971

[37] J Lee A L G Aitken S H Lee and P K BhattacharyaldquoResponsivity and Impact ionisation coefficients of Si

1minus119909Ge119909

photodiodesrdquo IEEE Electron Devices vol 43 no 6 pp 977ndash9811996

[38] K Yeom J M Hincley and J Singh ldquoCalculation of electronand hole impact ionisation coefficients in SiGe alloysrdquo Journalof Applied Physics vol 80 no 12 pp 6773ndash6782 1996

[39] M Ershov and V Ryzhii ldquoHigh field electron transport in SiGealloyrdquo Japanese Journal of Applied Physics vol 33 no 3 pp1365ndash1371 1994

[40] T Yamada and D K Ferry ldquoMontecarlo simulation of holetransport in strained Si

1minus119909Ge119909rdquo Solid-State Electronics vol 38

no 4 pp 881ndash890 1995[41] D L Scharfetter and H K Gummel ldquoLarge-signal analysis of

a silicon read diode oscillatorrdquo IEEE Transactions on ElectronDevices vol 6 no 1 pp 64ndash77 1969

[42] J F Luy A Casel W Behr and E Kasper ldquoA 90-GHz double-drift IMPATT diode made with Si MBErdquo IEEE Transactions onElectron Devices vol 34 no 5 pp 1084ndash1089 1987

[43] C Dalle P A Rolland and G Lieti ldquoFlat doping profiledouble-drift silicon IMPATT for reliable CW high-power high-efficiency generation in the 94-GHz windowrdquo IEEE Transac-tions on Electron Devices vol 37 no 1 pp 227ndash236 1990

[44] J F Luy H Jorke H Kibbel A Casel and E Kasper ldquoSiSiGeheterostructure mitatt dioderdquo Electronics Letters vol 24 no 22pp 1386ndash1387 1988

International Journal of

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Active and Passive Electronic Components

Control Scienceand Engineering

Journal of



RotatingMachinery


Hindawi Publishing Corporation httpwwwhindawicom

Journal ofEngineeringVolume 2014

Submit your manuscripts athttpwwwhindawicom

VLSI Design



Shock and Vibration


Civil EngineeringAdvances in

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Electrical and Computer Engineering

Journal of

Advances inOptoElectronics


Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

SensorsJournal of


Modelling amp Simulation in EngineeringHindawi Publishing Corporation httpwwwhindawicom Volume 2014


Chemical EngineeringInternational Journal of Antennas and

Propagation




Navigation and Observation



DistributedSensor Networks



119899+

Si

(Si1minus119909Ge119909)

119899

Si

(Si) (Si)(Si1minus119909Ge119909)

119901+

119901

Si1minus119909Ge119909 Si1minus119909Ge119909

119909 = 0 119909119860

119909119860

1 119909119895 1199091198602 119882

119882119899119882119901

Figure 1 One-dimensional schematics of the Si sim Si1minus119909

Ge119909aniso-

type heterojunction DDRMITATT devices

MITATT devices can provide higher efficiency higher outputpower and lower noise as compared to normal IMPATTdiodes The effect of tunneling on the high frequency prop-erties of DDR Si IMPATTs operating at millimeter-wave andterahertz frequencies was studied and reported by Acharyyaet al in their earlier paper [24 25] which showed that thecritical background doping concentration and operating fre-quency above which tunneling effect becomes predominantare 50 times 1023mminus3 and 260GHz respectivelyThemillimeter-wave performance of IMPATTs operating in MITATT modewas studied by Acharyya et al from the shift of avalanchetransit time (ATT) phase delay and reported in [26] Thereported results show that with increasing frequency the shiftof ATT phase delay increases which explains the physicalreason behind the deterioration of millimeter-wave perfor-mance of the device at higher frequencies Since tunneling isa noiseless phenomenon it is expected that the noise level inMITATTs will be lower than that in IMPATTs Furthermoreit is reported [27] that heterojunction IMPATTs have lowernoise level than their homojunction counterparts All thesefacts have inspired the authors to study the noise performanceof four types of Si sim Si

1minus119909Ge119909anisotype heterojunction

DDR structures of MITATT devices at W band In this studyonly two different mole fractions of Ge 119909 = 01 and 119909 =

03 are considered The performance of different structuresof heterojunction DDR MITATTs is compared with theirhomojunction counterpart based on Si operating at the samefrequency band

2 Simulation Method to Studythe Noise Properties

One-dimensional model of reverse biased Si sim Si1minus119909

Ge119909

DDR MITATT device shown in Figure 1 is considered fornoise analysis The DC electric field and current densityprofiles in the depletion layer of the device are obtainedfrom simultaneous numerical solution of fundamental deviceequations that is Poissonrsquos equation combined carrier conti-nuity equation in the steady state current density equationsand mobile space charge equation subject to appropriateboundary conditions as discussed in detail in the earlierpapers by the authors of [24ndash26] A double-iterative simula-tion method described elsewhere [17] is used to solve theseequations and to obtain the electric field and current densityprofiles The boundary conditions for the electric field at the

depletion layer edges that is at 119909 = 0 and 119909 = 119882 are givenby

120585 (0) = 0 120585 (119882) = 0 (1)

Similarly the boundary conditions for normalized currentdensity 119875(119909) = (119869

119901(119909) minus 119869

119899(119909))119869

0(where the total current

density 1198690= 119869119899(119909) + 119869

119901(119909) where 119869

119899(119909) and 119869

119901(119909) are the

electron and hole current densities respectively at the spacepoint 119909) at the depletion layer edges are given by

119875 (0) = (2

119872119901(0)

minus 1) 119875 (119882) = (1 minus2

119872119899(119882)

)

(2)

where 119872119899(119882) and 119872

119901(0) are respectively the electron and

hole multiplication factors at the depletion layer edges whosevalues are of the order of 106 under dark or unilluminatedcondition of the device

The magnitude of peak field at the junction (120585119901) break-

down voltage (119881119861) the widths of avalanche and drift zones

(119909119860and119909119863 where119909

119863=119889119899+119889119901) and the voltage drops across

these zones (119881119860 119881119863= 119881119861

minus 119881119860) are obtained from double-

iterative DC simulation program These values are fed backas input parameters in the small-signal simulation programto obtain the admittance properties of the device such asavalanche resonance frequency (119891

119886) optimum frequency

(119891119901) negative conductance (119866(120596)) and corresponding sus-

ceptance (119861(120596)) as functions of frequency Two second-order differential equations are framed by resolving the diodeimpedance 119885(119909 120596) into its real part 119877(119909 120596) and imaginarypart 119883(119909 120596) [18 19 24 25 28ndash31] Here 119885(119909 120596) = 119877(119909 120596) +

119895119883(119909 120596) where 119877(119909 120596) and 119883(119909 120596) are respectively thenegative specific resistance and specific reactance at the spacepoint 119909 for angular frequency of 120596 (frequency 119891 = 2120587120596)A double-iterative simulation over the initial choice of thevalues of 119877 and 119883 described in details in [18] is used to solvesimultaneously the two above said second order differentialequations subject to appropriate boundary conditions at thedepletion layer edges The spatial profiles of negative specificresistance and specific reactance (ie 119877(119909 120596) versus 119909 and119883(119909 120596) versus 119909) for a particular frequency are obtainedfrom the above solution within the depletion layer of thedevice The device negative resistance (119885

119877(120596)) and reactance

(119885119883(120596)) are obtained from the numerical integration of the

119877(119909 120596) and119883(119909 120596) profiles over the space-charge layerwidth(119882) Thus

119885119877(120596) = int

119882

0

119877 (119909 120596) 119889119909 119885119883(120596) = int

119882

0

119883 (119909 120596) 119889119909

(3)

The impedance of the device is given by 119885119863(120596) = 119885

119877(120596) +

119895119885119883(120596) and the device admittance is 119884

119863(120596) = 1119885

119863(120596) =

119866(120596) + 119895 119861(120596) The negative conductance and corresponding



|119866 (120596)| =119885119877(120596)

(119885119877(120596)2+ 119885119883(120596)2)

|119861 (120596)| =minus119885119883(120596)

(119885119877(120596)2+ 119885119883(120596)2)

(4)


1015840) = 119890119903(119909 1199091015840) + 119895 119890









1015840) is first


1015840) over the



119881119879(1199091015840) = int

119882

0

119890 (119909 1199091015840) 119889119909 (5)


119885119879(1199091015840) =

119881119879(1199091015840)

119868119873

(1199091015840) (6)


1198891199091015840 due to 120574(119909


is obtained from

⟨V2

119899⟩ = 2119902

2sdot 119889119891 sdot 119860int

10038161003816100381610038161003816119885119879(1199091015840)10038161003816100381610038161003816

2

120574 (1199091015840) 1198891199091015840 (7)




NM =⟨V2119899⟩119889119891

4119870119861119879 (minus119885

119877minus 119877119878) (8)









1minus119909Ge119909(119909 = 01 and 119909 =


1minus119909Ge119909(119909 = 01 and 119909 = 03)






119904) are taken


119863119873119860) of all different


+- and119901+-layers (119873






07Ge03 n-Si09Ge01

sim








119860)



119899+119882119901)




119861) is





119901(120583m) 119873

119863(times1023 mminus3) 119873

119860(times1023 mminus3) 119873

119899+ (times1025 mminus3) 119873

119901+ (times1025 mminus3) 119863

119895(120583m)dagger








120585119901(times107 Vmminus1) 60125 36760 35666 35534 33656

119881119861(V) 2389 1289 1181 1140 1108

119881119860(V) 1634 667 606 437 407

119909119860(120583m) 0354 0210 0204 0166 0162

119909119860119882 () 4539 3182 3186 2594 2455

120578 () 1006 1536 1549 1964 2015119891119901(GHz) 106 94 96 95 94

119866119901(times107 Smminus2) 46593 83760 10594 10441 11790

119861119901(times107 Smminus2) 17320 12252 90710 12102 42031

119876119901(= minus119861

119901119866119901) 372 146 086 116 036

119885119877(times10minus9Ωm2) 14484 38026 54463 40869 75254

119875RF (mW) 64744 57147 56322 71086 77329⟨V119899

2⟩119889119891

(times10minus16 V2 sec) 3951 375 185 139 082

NM (dB) 4000 3742 3654 3427 3309


1198601to 119909 = 119909



NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

0

1

2

3

4

5

6

7times10

7


minus7

119899-side 119901-side

Junction

Position (m)

Elec

tric

fiel

d (V

mminus1)





119901) and neg-



119901 119885119877) are



= minus119861119901119866119901



119861) of n-Si

09Ge01

sim 119875-Si and



times107

0

05

1

15

2

25times10

8


Susc

epta

nce (

S mminus2)

85GHz94GHz

94GHz

110GHz

110GHz

110GHz 110GHz106GHz

120GHz

85GHz


96GHz

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2



minus7

15

10

5

0

minus5

minus10

minus15

minus20

minus25

times10minus3

Position (m)

Resis

tivity

(Ohm

middotm)


NSPSNSpSG1NSpSG2

nSGPS1nSGPS2


n-Si07Ge03



output (119875RF = 120578 times 119881119861






NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

109

1010

1011

1012

10minus19

10minus18

10minus17

10minus16

10minus15

10minus14

Frequency (Hz)

Noi

se sp

ectr

al d

ensit

y (V

2s)










04Ge06







85 90 95 100 105 110 115 120 125 130 13510

20

30

40

50

60

70

Frequency (Hz)

Noi

se m

easu

re (d

B)

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2





5 Conclusions





07Ge03


References



































052In048












1minus119909Ge119909













RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation











|119866 (120596)| =119885119877(120596)

(119885119877(120596)2+ 119885119883(120596)2)

|119861 (120596)| =minus119885119883(120596)

(119885119877(120596)2+ 119885119883(120596)2)

(4)


1015840) = 119890119903(119909 1199091015840) + 119895 119890









1015840) is first


1015840) over the



119881119879(1199091015840) = int

119882

0

119890 (119909 1199091015840) 119889119909 (5)


119885119879(1199091015840) =

119881119879(1199091015840)

119868119873

(1199091015840) (6)


1198891199091015840 due to 120574(119909


is obtained from

⟨V2

119899⟩ = 2119902

2sdot 119889119891 sdot 119860int

10038161003816100381610038161003816119885119879(1199091015840)10038161003816100381610038161003816

2

120574 (1199091015840) 1198891199091015840 (7)




NM =⟨V2119899⟩119889119891

4119870119861119879 (minus119885

119877minus 119877119878) (8)









1minus119909Ge119909(119909 = 01 and 119909 =


1minus119909Ge119909(119909 = 01 and 119909 = 03)






119904) are taken


119863119873119860) of all different


+- and119901+-layers (119873






07Ge03 n-Si09Ge01

sim








119860)



119899+119882119901)




119861) is





119901(120583m) 119873

119863(times1023 mminus3) 119873

119860(times1023 mminus3) 119873

119899+ (times1025 mminus3) 119873

119901+ (times1025 mminus3) 119863

119895(120583m)dagger








120585119901(times107 Vmminus1) 60125 36760 35666 35534 33656

119881119861(V) 2389 1289 1181 1140 1108

119881119860(V) 1634 667 606 437 407

119909119860(120583m) 0354 0210 0204 0166 0162

119909119860119882 () 4539 3182 3186 2594 2455

120578 () 1006 1536 1549 1964 2015119891119901(GHz) 106 94 96 95 94

119866119901(times107 Smminus2) 46593 83760 10594 10441 11790

119861119901(times107 Smminus2) 17320 12252 90710 12102 42031

119876119901(= minus119861

119901119866119901) 372 146 086 116 036

119885119877(times10minus9Ωm2) 14484 38026 54463 40869 75254

119875RF (mW) 64744 57147 56322 71086 77329⟨V119899

2⟩119889119891

(times10minus16 V2 sec) 3951 375 185 139 082

NM (dB) 4000 3742 3654 3427 3309


1198601to 119909 = 119909



NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

0

1

2

3

4

5

6

7times10

7


minus7

119899-side 119901-side

Junction

Position (m)

Elec

tric

fiel

d (V

mminus1)





119901) and neg-



119901 119885119877) are



= minus119861119901119866119901



119861) of n-Si

09Ge01

sim 119875-Si and



times107

0

05

1

15

2

25times10

8


Susc

epta

nce (

S mminus2)

85GHz94GHz

94GHz

110GHz

110GHz

110GHz 110GHz106GHz

120GHz

85GHz


96GHz

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2



minus7

15

10

5

0

minus5

minus10

minus15

minus20

minus25

times10minus3

Position (m)

Resis

tivity

(Ohm

middotm)


NSPSNSpSG1NSpSG2

nSGPS1nSGPS2


n-Si07Ge03



output (119875RF = 120578 times 119881119861






NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

109

1010

1011

1012

10minus19

10minus18

10minus17

10minus16

10minus15

10minus14

Frequency (Hz)

Noi

se sp

ectr

al d

ensit

y (V

2s)










04Ge06







85 90 95 100 105 110 115 120 125 130 13510

20

30

40

50

60

70

Frequency (Hz)

Noi

se m

easu

re (d

B)

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2





5 Conclusions





07Ge03


References



































052In048












1minus119909Ge119909













RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation












119901(120583m) 119873

119863(times1023 mminus3) 119873

119860(times1023 mminus3) 119873

119899+ (times1025 mminus3) 119873

119901+ (times1025 mminus3) 119863

119895(120583m)dagger








120585119901(times107 Vmminus1) 60125 36760 35666 35534 33656

119881119861(V) 2389 1289 1181 1140 1108

119881119860(V) 1634 667 606 437 407

119909119860(120583m) 0354 0210 0204 0166 0162

119909119860119882 () 4539 3182 3186 2594 2455

120578 () 1006 1536 1549 1964 2015119891119901(GHz) 106 94 96 95 94

119866119901(times107 Smminus2) 46593 83760 10594 10441 11790

119861119901(times107 Smminus2) 17320 12252 90710 12102 42031

119876119901(= minus119861

119901119866119901) 372 146 086 116 036

119885119877(times10minus9Ωm2) 14484 38026 54463 40869 75254

119875RF (mW) 64744 57147 56322 71086 77329⟨V119899

2⟩119889119891

(times10minus16 V2 sec) 3951 375 185 139 082

NM (dB) 4000 3742 3654 3427 3309


1198601to 119909 = 119909



NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

0

1

2

3

4

5

6

7times10

7


minus7

119899-side 119901-side

Junction

Position (m)

Elec

tric

fiel

d (V

mminus1)





119901) and neg-



119901 119885119877) are



= minus119861119901119866119901



119861) of n-Si

09Ge01

sim 119875-Si and



times107

0

05

1

15

2

25times10

8


Susc

epta

nce (

S mminus2)

85GHz94GHz

94GHz

110GHz

110GHz

110GHz 110GHz106GHz

120GHz

85GHz


96GHz

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2



minus7

15

10

5

0

minus5

minus10

minus15

minus20

minus25

times10minus3

Position (m)

Resis

tivity

(Ohm

middotm)


NSPSNSpSG1NSpSG2

nSGPS1nSGPS2


n-Si07Ge03



output (119875RF = 120578 times 119881119861






NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

109

1010

1011

1012

10minus19

10minus18

10minus17

10minus16

10minus15

10minus14

Frequency (Hz)

Noi

se sp

ectr

al d

ensit

y (V

2s)










04Ge06







85 90 95 100 105 110 115 120 125 130 13510

20

30

40

50

60

70

Frequency (Hz)

Noi

se m

easu

re (d

B)

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2





5 Conclusions





07Ge03


References



































052In048












1minus119909Ge119909













RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation











times107

0

05

1

15

2

25times10

8


Susc

epta

nce (

S mminus2)

85GHz94GHz

94GHz

110GHz

110GHz

110GHz 110GHz106GHz

120GHz

85GHz


96GHz

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2



minus7

15

10

5

0

minus5

minus10

minus15

minus20

minus25

times10minus3

Position (m)

Resis

tivity

(Ohm

middotm)


NSPSNSpSG1NSpSG2

nSGPS1nSGPS2


n-Si07Ge03



output (119875RF = 120578 times 119881119861






NSPSNSpSG1NSpSG2

nSGPS1nSGPS2

109

1010

1011

1012

10minus19

10minus18

10minus17

10minus16

10minus15

10minus14

Frequency (Hz)

Noi

se sp

ectr

al d

ensit

y (V

2s)










04Ge06







85 90 95 100 105 110 115 120 125 130 13510

20

30

40

50

60

70

Frequency (Hz)

Noi

se m

easu

re (d

B)

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2





5 Conclusions





07Ge03


References



































052In048












1minus119909Ge119909













RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










85 90 95 100 105 110 115 120 125 130 13510

20

30

40

50

60

70

Frequency (Hz)

Noi

se m

easu

re (d

B)

NSPSNSpSG1NSpSG2

nSGPS1nSGPS2





5 Conclusions





07Ge03


References



































052In048












1minus119909Ge119909













RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation


















052In048












1minus119909Ge119909













RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation











RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation









Documents

Research Article Noise Performance of Heterojunction …downloads.hindawi.com/journals/apec/2013/720191.pdf · Noise Performance of Heterojunction DDR MITATT ... analyzed the high