Office: ITE 459
Phone: (860) 486-2666
- Ph.D, Electrical and Electronics Engineering, Bilkent University, 2004
- M.S., Electrical and Electronics Engineering, Bilkent University, 1996
- B.S., Electrical and Electronics Engineering, Bilkent University, 1992
|2017 –||Assistant Professor, Electrical and Computer Engineering, University of Connecticut|
|2016 – 2017||Research Fellow, Electrical and Computer Engineering, Utah State University|
|2011 – 2016||Assistant Professor, Materials Science and Nanotechnology & National Nanotechnology Research Center (UNAM), Bilkent University|
|2008 – 2011||Research Assistant Professor, Materials Science and Nanotechnology & National Nanotechnology Research Center (UNAM), Bilkent University|
|2007 – 2008||Research Scientist, Electrical and Computer Engineering, Utah State University & Cornell Nanoscale Science and Technology Facility (CNF)|
|2004 – 2007||Postdoctoral Research Associate, Electrical and Computer Engineering, Virginia Commonwealth University|
Materials & Growth
- III-Nitride semiconductor materials (AlN, GaN, InN)
- III-Nitride thin-film growth (Plasma-enhanced atomic layer deposition, MOCVD)
- Metal-Oxide semiconductor materials (ZnO, TiO2, SnO2)
- Metal-Oxide thin-film growth (DC/RF-Sputtering, atomic layer deposition)
- Piezo-electric thin-films (AlN, ZnO)
- Tunable/smart alloys (Phase change – GST / Tunable dielectric – BST)
- Durable materials (BN)
Devices & Applications
- Opto-electronics: Photodetectors, LEDs based on III-Nitride compounds
- Electronics: High-power/high-frequency III-Nitride transistors, thin-film transistors (TFTs)
- Renewable energy: Inorganic solar cells, hybrid organic/inorganic solar cells, dye synthesized solar cells (DSSC)
- Sensing: Chemical/gas sensors for environmental monitoring using ZnO/SnO2/TiO2 nanostructures and ZnO/AlN SAW sensors
- Wireless communication: Novel materials & architectures for next-generation smart/green wireless communication systems
- Functional surfaces: Photocatalytic coatings based on hybrid organic/inorganic nano-structures using ALD
- Health monitoring & Medical diagnosis: Biological sensors, micro-needles, Lab-on-a-Chip (LoC) devices & systems
- National security and defense: Reconfigurable RF-antenna systems for agile & secure communication systems
Memberships of Scientific Societies
1999 – IEEE, MRS, AVS, SPIE
Prizes & Awards
- 4 Student Finalist Awards by Biyikli Group members in Annual AVS-ALD Conferences (Boston, MA – 2011; San Diego, CA – 2013; Portland, OR – 2015; Denver, CO – 2017)
- Middle East Technical University (METU) Prof. Mustafa Necati Parlar Education and Research Foundation – Research Incentive Award (2013)
- European Research Executive Agency – Marie Curie Fellowship – International Re-integration Grant (MC-IRG) Award (2010)
- M. A. Khalily, N. Biyikli, et al.,“Facile synthesis of three-dimensional Pt-TiO2 nanonetworks: Highly active catalyst for hydrolytic dehydrogenation of ammonia borane”, Angewandte Chemie 55, 12257 (2016).
- A. Haider, N. Biyikli, et al.,“Low-temperature grown wurtzite InxGa1-xN thin films via hollow cathode plasma-assisted atomic layer deposition”, Journal of Materials Chemistry (C) 3, 9620 (2015).
- F. Kayaci, N. Biyikli, et al.,“Role of zinc interstitials and oxygen vacancies of ZnO in photocatalysis: A bottom-up approach to control the defect density”, Nanoscale 6, 10224 (2014).
- C. Ozgit-Akgun, N. Biyikli, et al., “Hollow-cathode plasma-assisted atomic layer deposition of crystalline AlN, GaN, and AlxGa1-xN thin films at low temperature”, Journal of Materials Chemistry (C) 2, 2123 (2014) [Front Cover Article]. Major breakthrough: A novel method for plasma-assisted ALD which enabled a dramatic decrease in impurity content of low-temperature-grown GaN thin films is proposed. Moreover, for the first time, the self-limiting growth for crystalline AlGaN alloys along with bandgap tuning is demonstrated.
- A. Haider, N. Biyikli, “Fabrication of BN/AlN bishell hollow nanofibers by electrospinning and atomic layer deposition”, APL Materials 2, 096109 (2014). Key contribution: A low-temperature process to fabricate multi-layered hollow crystalline BN/AlN nanostructures on polymeric nanofibrous templates is developed.
- S. Bolat, N. Biyikli, et al.,“Low temperature thin film transistors with hollow cathode plasma-assisted atomic layer deposition based GaN channels”, Applied Physics Letters 104, 243505 (2014). Major breakthrough: The lowest process temperature budget (growth and fabrication @ T<200°C) reported ever for GaN-based thin-film transistors by using our own hollow-cathode plasma-assisted ALD (HCPA-ALD) technique is achieved.
- C. Ozgit-Akgun, N. Biyikli, et al.,“Fabrication of flexible polymer-GaN core-shell nanofibers by the combination of electrospinning and hollow cathode plasma-assisted atomic layer deposition”, Journal of Materials Chemistry (C) 3, 5199 (2015). (Key advance: Fabricating flexible core-shell GaN nanofibers via low-temperature HCPA-ALD, which might have potential use in flexible electronics is succeeded)
- F. Kayaci, N. Biyikli, et al.,“Selective isolation of the electron or hole in photocatalysis: ZnO–TiO2 and TiO2–ZnO core-shell structured heterojunction nanofibres via electrospinning and atomic layer deposition”, Nanoscale 6, 5735 (2014) [Front Cover Article]. (Key contribution: Novel core-shell metal-oxide nanofiber structures demonstrating significantly improved photocatalysis performance)
- C. Ozgit, N. Biyikli, et al.,“Template-based synthesis of aluminum nitride hollow nanofibers via plasma-enhanced atomic layer deposition”, Journal of the American Ceramics Society 96, 916 (2013).
- C. Ozgit, N. Biyikli, et al.,“Self-limiting low-temperature growth of crystalline AlN thin films by plasma-enhanced atomic layer deposition”, Thin Solid Films 520, 2750 (2012). Major breakthrough: The self-limiting growth of crystalline AlN thin films at extremely low temperatures down to 100°C is accomplished.
- F. Kayaci, N. Biyikli, et al.,“Polymer-Inorganic Core-Shell Nanofibers by Electrospinning and Atomic Layer Deposition: Flexible Nylon-ZnO Core-Shell Nanofiber Mats and Their Photocatalytic Activity”, ACS Applied Materials & Interfaces 4, 6185 (2012).
- H. Ceylan, N. Biyikli, et al., “Size-controlled conformal nanofabrication of biotemplated three-dimensional TiO2 and ZnO nanonetworks”, Scientific Reports, 3, 2306 (2013). Key advance: We used the ultimate conformality and precision of our ALD recipes to coat highly 3D nano-biotemplates to craft functional metal-oxide nanomaterials and demonstrated intensely improved photocatalytic activity.
- N. Biyikli, et al.,”Magneto-transport properties of MOVPE-grown AlxGa1-xN/AlN/GaN heterostructures with high-mobility two-dimensional electron gas”, Journal of Applied Physics 101, 113710 (2007). Key contribution: The III-nitride HEMT epilayers are grown using two different lateral overgrowth techniques and the low-temperature mobility values are characterized which resulted in significantly enhanced 2DEG mobility when compared to conventional HEMT structures.
- N. Biyikli, et al.,”Solar-blind AlGaN-based Schottky photodiodes with low noise and high detectivity”, Applied Physics Letters 81, 3272 (2002). Key contribution: We demonstrated AlGaN-based Schottky photodiodes showing solar blindness with record detectivity performance approaching PMT sensitivity levels.
- N. Biyikli, et al.,”45-GHz Bandwidth-Efficiency Resonant-Cavity-Enhanced ITO-Schottky Photodiodes”, IEEE Photonics Technology Letters 13, 705 (2001). Key advance: We developed AlGaAs/GaAs-based RCE-Schottky photodiodes exhibiting the highest bandwidth-efficiency performance reported for vertical type of photodetectors.
Full list of publications can be reached here.
Invited Talks at Peer-Reviewed International Conferences (Since 2013)
- Biyikli, A. Haider, P. Deminskyi, “Self-aligned nanoscale processing solutions via selective atomic layer deposition of oxide, nitride, and metallic films”, SPIE Optics + Photonics 2017, San Diego, CA, 6 – 10 August (2017).
- Biyikli et al.,“Low-temperature plasma-assisted atomic layer deposition growth technology for group III-Nitride hetero-/nano-structures and their (opto)electronic device applications”, AVS 63rd International Symposium and Exhibition, Nashville, TN, 6 – 11 November (2016).
- Biyikli et al.,“Template-assisted synthesis of III-nitride and metal-oxide nano-heterostructures using low-temperature atomic layer deposition for energy, sensing, and catalysis applications”, SPIE Optics + Photonics 2015, San Diego, CA, 9 – 13 August (2015).
- Biyikli, et al.,“Hollow-cathode plasma-assisted atomic layer deposition: a novel route for low-temperature synthesis of crystalline III-nitride thin films and nanostructures”, IEEE 35th International Conference on Electronics and Nanotechnology (IEEE-ELNANO), Kyiv, Ukraine, April 21-24 (2015).
- Alevli, N. Biyikli, et al., “Effect of Reactor Pressure on The Optical and Electrical Properties of HP-CVD Grown InN Films”, MRS – 5th International Symposium on Growth of III-Nitrides (ISGN-5), Atlanta, GA, May 18-22 (2014).
- Ozgit-Akgun, N. Biyikli, et al.,“Low-Temperature Plasma-enhanced Atomic Layer Deposition of Crystalline III-Nitride Thin Films” International Semiconductor Science and Technology Conference (ISSTC-2014), Istanbul, Turkey, January 13-15 (2014).
- Ozgit-Akgun, N. Biyikli, et al.,“Plasma-Enhanced Atomic Layer Deposition of III-Nitride Thin Films”, 224thECS Meeting, San Francisco, CA, October 27 – November 1 (2013).