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Nanofabrication and characterization Nanofabrication and characterization of of ZnO nanorod arrays and ZnO nanorod arrays and

branchedbranched nanorods for nanorods for device device applicationsapplications

Academy of Sciences of Moldova

Oleg LUPAN Technical University of Moldova, MD 2004 Chisinau, Moldova University of Central Florida, Orlando, FL 32816

lupan@physics.ucf.edulupan@mail.utm.md

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Collaborations with the UCF Teams

Synthesis and advising – Dr. Lee ChowMCF - XRD, FIB device fabrication – Dr. G. Chai XPS – Dr. B. Roldan, Dr. A. Naitabdi

Micro-Raman – Dr. A. Schulte, S. ParkCL spectra – Dr. L. Chernyak, L. Lopatiuk-TirpakTEM – Dr. Helge Heinrich SEM, EDX – Dr. G. Chai, H. Khallah

& Equipment available at the UCF and MCF

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Collaborations with the Moldova Teams

MD. Scintific advising – Prof. Dr.hab. T. ShishiyanuRPP, Hall – Dr. S. ShishiyanuGas sensitivity – Prof. Dr. V. SonteaCharacterizations – Dr. S. Railean

Technical University of MoldovaTechnical University of Moldova

PL – Dr. Hab. V. Ursaki, Institute of Applied Physics, MD Acad. I. Tigineanu, Academy of Sciences of MoldovaEDX, SEM – PhD. E. Monaico, NCMST, TUM, Moldova

Academy of Sciences of Moldova

National Center for Materials Study and Testing

Technical University of Moldova

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Introduction and Motivation ZnO is a key functional material exhibiting :

near-ultraviolet emission , transparent conductivity

semiconducting, magnetic, and piezoelectric properties.

It has a : wide direct band gap (3.37 eV), &

large exciton binding energy (60 meV) excellent chemical, mechanical, and thermal stability [1, 2]

Zinc oxide has extensive commercial use during the past 100 years [3] in:

optoelectronics nano/microelectronics sensors, transducers, hydrogen storage material and biomedicine.

ZnO is a phosphor materials with ability to retain a high efficiency, even at low-voltage excitation [1–8].

Nanofabrication and characterization ofNanofabrication and characterization of ZnO nanorod ZnO nanorod arrays and branchedarrays and branched nano/microrods for device nano/microrods for device

applicationsapplications 4

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Introduction and Motivation Nanostructures,

-> nanorods, -> nanowires, -> nanotubes, -> nanobelts,

have attracted extraordinary attention for their potential applications in device and

interconnect integration in nanoelectronics and molecular

electronics.

Control the particle size & morphology of nanostructures

is of crucial importance from a fundamental and industrial point of view

Department of PhysicsDepartment of PhysicsUniversity of Central University of Central

FloridaFlorida

Department of Department of MicroelectronicsMicroelectronics

Technical University of Technical University of MoldovaMoldova

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DeviceDevice FabricationsFabricationsat the MCF, UCFat the MCF, UCF

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In-situ lift-out fabrication and characterizations of

ZnO branched nanorods - based nano/microsensors

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Conclusions The nanorod arrays and branched chemical deposited zinc

oxide as gas sensors &

solar cells.

The merit of this technology is in The merit of this technology is in simplicity of the process, economy in energy, structures with high efficiency, short duration, energy save, accessible auxiliary materials & nonsophisticated equipment.

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ConclusionsBy this technique has been fabricated different

shaped-nanosensors &

preliminary investigated their gas sensitivity to H2, O2, oxygen partial pressure,

UV sensitivity, relative

humidity, alcohol and ammonia gases.

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Future work We plan further investigations with different dopants and second

components in ZnO, etc architectures are underway other nanoarchitectures & nanostructures multilayer structures… Nanorod p-n junctions!!!!! & devices for sensor & high-tech applications of nanostructured

metal oxide material devices

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Acknowledgements This work described here was made possible in part

by an Award No.MTFP-1014 for young researchersof the Moldovan Research and Development Association

under the funding from the U.S. Civilian Research and Development Foundation (CRDF) with support from U.S. Department of State

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Acknowledgements Financial support by the Project 321b/s from the

Ministry of Education and Science of Moldova, and Project 032P from Supreme Council for

Research and Technological Development of the Academy of Sciences of Moldova

are gratefully acknowledgedare gratefully acknowledged.

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Publications - Dr. LUPAN Oleg et.al. Jan-May-2007

[1] O. Lupan, G. Chai, L. Chow, "Hydrogen nanosensor on single nanorod" US patent pending, May, 2007.

[2] S. Shishiyanu, T. Shsishiyanu, O. Lupan “Gas sensor" MD patent registered #4639 and pending, May, 2007.

[3] O. Lupan, L. Chow, SYNTHESIS AND CHARACTERIZATIONS OF ZnO NANORODS ARRAYS FOR SOLAR CELL AND CHEMICAL SENSOR APPLICATIONS, Proceedings of NSTI Nanotechnology Conference and Trade Show, May 20-24, 2007, Santa Clara, California, U.S.A., ISBN 1420063766 Vol. 4, pp. 457-460.

[4] O.Lupan, L. Chow, S. Shishiyanu, V. Ursaki, E. Monaico, T. Shishiyanu, B. Roldan, A. Naitabdi, A. Schulte, S. Park, Nanostructured zinc oxide synthesized by successive chemical solution deposition for solar cells and gas sensor applications, submitted to Materials Research Bulletin, April 2007.

[5] V. V. Ursaki, O. Lupan, L. Chow, I. M. Tiginyanu, V. Zalamai, Rapid thermal annealing induced change of the mechanism of multiphonon resonant Raman scattering from ZnO nanorods, submitted April, 2007, accepted Solid State Communications.

Other 5 submitted Papers to International peer-review Journals

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2 accepted Poster Papers accepted and Presented by Dr. LUPAN Oleg 20-24 May-2007 NSTI Nanotechnology

Conference and Trade Show, May 20-24, 2007, Santa Clara, California, U.S.A., ISBN 1420063766 Vol. 4, pp. 457-460

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Young generation of engineers and scientists in USA

Undergraduate students (4+) MSc (1+) Graduate students or PhD

students(3+)

& Moldova

Questions???

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Q & A, please ? !

Thank You !!!

lupan@physics.ucf.edulupanoleg@yahoo.com