7/31/2019 Cryogenic SPM

1/4

Low Temperature3He & 4He SPM Operation

in High Magnetic FieldsLowtemperaturesofbelow500mK

Highmagneticeldsofupto12T

Cryostatholdtimeofupto160h

ContinuousSPMoperationduring

magneticeldvariation

Springsuspensionformechanicaldecouplingbetweencryostatand

microscope

Cryogenic SPM System 160-V01/Mar.10

CryogenicSPMSystems

7/31/2019 Cryogenic SPM

2/4

Omicron NanoTechnology GmbH

www.omicron.de

High-performanceSPMoperationatlow temperatures and high magnetic

eldsputsstringentrequirementson

instrumentdesign.WiththeCryogenic

series,Omicronhasdevelopedasta-

bleandmultifunctionalplatformfor

delicate experimental conditions.

SPM operation at cryogenic temperatures is a

well-established technique and known to bekey to observation of topography and elec-tronic structure of atoms, clusters, molecules,islands and surfaces in general. A small lateraland vertical drift as well as the reduced ther-mal energy broadening of the local density ofstates at low temperatures are ideal pre-condi-tions for long term spectroscopy experiments.Furthermore, the reduced surface diffu-sion allows for atom manipulation includingmeasurements of the involved forces and thesystematic study of the adsorption behavior of

selected atoms and molecules.

Cryogenic UHV bottom loader systems:

a 3He-Cryogenic STM system (in the front) and

a 4He-Cryogenic SFM system in the background.

These properties of a low temperature SPM systemin combination with high magnetic elds open up theaccess to a larger variety of measurements like Mag-netic Force Microscopy, Magnetic Exchange Force Mi-croscopy or Spin Polarized Scanning Tunneling Micro-scopy and Spectroscopy, as shown in the example1).

BottomLoaderConcept

The system concept is based on a bottom loadercryostat from Oxford Instruments with various magnetconfgurations and two alternative cooling techniques: a

pumped 4He variable temperature insert for continuousSTM operation from 2.5 K up to 300 K and a 3He insertfor temperatures below 500 mK.Two different microscopes are available: a CryogenicSTM for ultimate STM/STS performance and an inter-ferometer-based Cryogenic SFM for AFM, STM, andMFM measurements. Using a rigid vertical manipula-tor, the cryostat insert with attached microscope canbe transferred to the STM chamber for in-situ tip/sample exchange (situated below the cryostat). Asecond custom-tailored chamber with a fast entryload lock serves for sample preparation purposes and

additional analysis techniques.

2

ProvenPerformance

7/31/2019 Cryogenic SPM

3/4

Omicron NanoTechnology GmbH

www.omicron.de

VersatilityandAccessibleSPMTechniques:ScanningTunnelingMicroscopyandSpectroscopy

SpinPolarizedTunnelingMicroscopyandSpectroscopy

InelasticTunnelingSpectroscopy

ScanningForceMicroscopyand-Spectroscopy

MagneticForceMicroscopy/MagneticExchangeForceMicroscopy

ElectrostaticForceMicroscopy/KelvinProbe

AtomManipulationTemperatureVariation

MagneticFieldVariation(SingleAxis,2D-or3DVectorField)

Spin-Polarized STM measurements obtained with a previous version of a Cryogenic SFM system at the Max-Planck Institute of

Microstructure Physics in Halle, Germany. Local modulation of spin polarization at 8 K 1):

a) Topography STM image of a triangular Co island on Cu(111). The Co island is two atomic layers in height (~0.4 nm) and has a base

length of 12 nm. Ugap

=-0.1 V, IT=1 nA.

b) and c) Two dI/dV images of the Co island measured at B=-1.1 T but with different magnetization congurations between the magne-

tic tunneling tip (Cr-Co-W) and the Co island: antiparallel and parallel (see insert).

d) dI/dV asymmetry map calculated from b) and c) showing the local modulation of spin polarization which can be ascribed to the

difference between the spatially modulated density of states of the majority spin and the non-modulated minority spin contribution.

Reference: 1)H. Oka, P.A. Ignatiev, S. Wedekind, G. Rodary, L. Niebergall, V.S. Stepanyuk, D. Sander and J. Kirschner, Science 327 (2010) 843

A B C

D

FascinatingResultsonSpin-PolarizedSTM:

3

7/31/2019 Cryogenic SPM

4/4

Cryogenic SPM System 160-V01/Mar.10

Printed by Druckerei und Verlag Klaus Koch GmbH

Specications and descriptions contained

in this brochure are subject to alteration without notice.

Headquarters:Omicron NanoTechnology GmbHLimburger Str. 7565232 Taunusstein, Germany

Tel. +49 (0) 61 28 / 987 - 0Fax +49 (0) 61 28 / 987 - 185Web: www.omicron.de orwww.omicron-instruments.com

e-mail: info@omicron.de

We have agents and partnersworldwide please check our web-site to nd your nearest contact.

How to contact usMinneapol is Pittsburgh East Grinstead Linkping PoznanMoscow

Beijing

Seoul

Tokyo

Taipei

Mumbai

Melbourne HeadquartersSales & ServiceSales

BucharestRomeSt. CannatMadridDenver Riyadh

Singapore

Cryogenic STM Cryogenic SFM

The microscope provides vertical and lateral

coarse positioning, 4 electrical contacts at

the sample plate, and in-situ exchangeable

tip carriers with three electrical contacts.

Atomic resolution on metal surfaces with pm

range stability and meV energy resolution

prove the performance of the system.

The Cryogenic SFM is a highly sensitive

interferometric AFM with 3D-coarse posi-

tioning designed for STM, AFM and MFM

measurements. The sample plate provides

10 electrical contacts. Exchangeable sensor

carriers feature 4 electrical contacts.

TechnicalInformation:

CryogenicSTM

Scanrange: XYZ = 6.5 m x 6.5 m x 0.8 m at RTXYZ = 1.2 m x 1.2 m x 0.15 m at 4.2 K

Resolution: atomic resolution STM2)

2Dcoarsepositioning:Z: ~6 mm, X: ~4 mm

4 electrical sample contacts

In-situexchangeabletipcarrierswiththreeelectricalcontacts

Cernoxtemperaturesensor

Measurementmodes:STM, STS, IETS, SP-STS, etc.

CryogenicSFM

Scanrange: XYZ = 20 m x 20 m x 2.2 m at RT

XYZ = 3.6 m x 3.6 m x 0.39 m at 4.2 K

Resolution: atomic resolution STM and AFM2)

3Dcoarsepositioning:X/Y: ~5 mm circle, Z: ~10 mm

10electricalsamplecontacts

In-situexchangeabletipcarrierswithfourelectricalcontacts

Cernoxtemperaturesensor

Measurementmodes:NC-AFM, C-AFM, MFM, KPFM, STM, STS,

IETS, SP-STS, etc.

StandardMagnetConfguration&Cryostat(othersonrequest):Verticalmagneticfeldoption: 6T

(higher magnetic felds on request)

3Dvectorfeldoption:

1D: BZ=6T, or B

X=1T, B

Y=1T

2D: BZ=2T and B

Xor B

Y=1T

3D: BZ=2T plus |B

XY|=1T

Temperaturerange:4He pumped insert: 2.5 K 300 K, continuously

(achieved: 1.8 K)3He insert: 500 mK 100 K

(achieved: < 400 mK)

Specifed4Heholdtime:60 h (achieved >160 h

- depending on cryostat confguration, magnet

operation and minimum temperature)

2) Please refer to quaranteed specications. Dependingon environmental conditions, site evaluation by Omicron.