Browsing by Author "Ünlü, M. S."

Now showing items 1-12 of 12

    • 100-GHz resonant cavity enhanced Schottky photodiodes 

      Onat, B. M.; Gökkavas, M.; Özbay, Ekmel; Ata, E. P.; Towe, E.; Ünlü, M. S. (Institute of Electrical and Electronics Engineers, 1998)
      Resonant cavity enhanced (RCE) photodiodes are promising candidates for applications in optical communications and interconnects where ultrafast high-efficiency detection is desirable. We have designed and fabricated RCE ...

    • 45 GHz bandwidth-efficiency resonant cavity enhanced ITO-Schottky photodiodes 

      Bıyıklı, Necmi; Kimukin, İbrahim; Aytür, Orhan; Özbay, Ekmel; Gökkavas, M.; Ünlü, M. S. (OSA, 2001)
      We demonstrated high-performance resonant cavity enhanced ITO-Schottky photodiodes. We achieved a peak efficiency of 75% around 820 nm with a 3-dB bandwidth of 60 GHz resulting in a bandwidth-efficiency product of 45 GHz.

    • 45-GHz bandwidth-efficiency resonant-cavity-enhanced ITO-Schottky photodiodes 

      Bıyıklı, Necmi; Kimukin, I.; Aytür, O.; Gökkavas, M.; Ünlü, M. S.; Özbay, Ekmel (IEEE, 2001)
      High-speed Schottky photodiodes suffer from low efficiency mainly due to the thin absorption layers and the semitransparent Schottky-contact metals. We have designed, fabricated and characterized high-speed and high-efficiency ...

    • Design and optimization of high-speed resonant cavity enhanced Schottky photodiodes 

      Gökkavas, M.; Onat, B. M.; Özbay, Ekmel; Ata, E. P.; Xu, J.; Towe, E.; Ünlü, M. S. (Institute of Electrical and Electronics Engineers, 1999-02)
      Resonant cavity enhanced (RCE) photodiodes (PD's) are promising candidates for applications in optical communications and interconnects where high-speed high-efficiency photodetection is desirable. In RCE structures, the ...

    • Fabrication of high-speed resonant cavity enhanced schottky photodiodes 

      Özbay, Ekmel; Islam, M. S.; Onat, B.; Gökkavas, M.; Aytür, O.; Tuttle, G.; Towe, E.; Henderson, R. H.; Ünlü, M. S. (Institute of Electrical and Electronics Engineers, 1997-05)
      We report the fabrication and testing of a GaAs-based high-speed resonant cavity enhanced (RCE) Schottky photodiode. The top-illuminated RCE detector is constructed by integrating a Schottky contact, a thin absorption ...

    • High bandwidth-efficiency resonant cavity enhanced Schottky photodiodes for 800-850 nm wavelength operation 

      Ünlü, M. S.; Gökkavas, M.; Onat, B. M.; Ata, E.; Özbay, Ekmel; Mirin, R. P.; Knopp, K. J.; Bertness, K. A.; Christensen, D. H. (A I P Publishing LLC, 1998-05-25)
      High-speed resonant cavity enhanced Schottky photodiodes operating in 800-850 nm wavelength region are demonstrated. The devices are fabricated in the AlGaAs/GaAs material system. The Schottky contact is a semitransparent ...

    • High-speed >90% quantum-efficiency p-i-n photodiodes with a resonance wavelength adjustable in the 795-835 nm range 

      Özbay, Ekmel; Kimukin, İ.; Bıyıklı, Necmi; Aytür, O.; Gökkavas, M.; Ulu, G.; Ünlü, M. S.; Mirin, R. P.; Bertness, K. A.; Christensen, D. H. (A I P Publishing LLC, 1999-02-22)
      We report GaAs/AlGaAs-based high-speed, high-efficiency, resonant cavity enhanced p-i-n photodiodes. The devices were fabricated by using a microwave-compatible fabrication process. By using a postprocess recess etch, we ...

    • High-speed high-efficiency large-area resonant cavity enhanced p-i-n photodiodes for multimode fiber communications 

      Gökkavas, M.; Dosunmu, O.; Ünlü, M. S.; Ulu, G.; Mirin, R. P.; Christensen, D. H.; Özbay, Ekmel (IEEE, 2001)
      In this letter, we report AlGaAs–GaAs p-i-n photodiodes with a 3-dB bandwidth in excess of 10 GHz for devices as large as 60- m diameter. Resonant cavity enhanced photodetection is employed to improve quantum efficiency, ...

    • High-speed high-efficiency resonant cavity enhanced photodiodes 

      Özbay, Ekmel; Kimukin, I.; Bıyıklı, N.; Aytür, O.; Gökkavas, M.; Ulu, G.; Ünlü, M. S.; Mirin, R. P.; Bertness, K. A.; Christensen, D. H.; Towe, E.; Tuttle, G. (Society of Photo-Optical Instrumentation Engineers, Bellingham, WA, United States, 1999)
      In this paper, we review our research efforts on RCE high-speed high-efficiency p-i-n and Schottky photodiodes. Using a microwave compatible planar fabrication process, we have designed and fabricated GaAs based RCE ...

    • High-speed resonant-cavity-enhanced Schottky photodiodes 

      Ata, Erhan P.; Bıyıklı, Necmi; Demirel, Ekrem; Özbay, Ekmel; Gökkavas, M.; Onat, B.; Ünlü, M. S.; Tuttle, G. (IEEE, 1998)
      The top-illuminated Schottky photodiodes were fabricated by a microwave-compatible monolithic microfabrication process. Fabrication started with formation of ohmic contacts to n+ layers. Mesa isolation was followed by a ...

    • High-speed widely-tunable >90% quantum-efficiency resonant cavity enhanced p-i-n photodiodes 

      Bıyıklı, Necmi; Kimukin, İbrahim; Aytür, Orhan; Gökkavas, M.; Ulu, G.; Mirin, R.; Christensen, D. H.; Ünlü, M. S.; Özbay, Ekmel (IEEE, 1998)
      Widely-tunable high-speed resonant cavity enhanced p-i-n photodiodes were designed, fabricated and tested for operation around 820 nm. The structure was grown by solid-source MBE on GaAs substrates and features high-reflectivity ...

    • Improved selectivity from a wavelength addressable device for wireless stimulation of neural tissue 

      Seymour, E. Ç.; Freedman, D. S.; Gökkavas, M.; Özbay, Ekmel; Sahin, M.; Ünlü, M. S. (Frontiers Research Foundation, 2014)
      Electrical neural stimulation with micro electrodes is a promising technique for restoring lost functions in the central nervous system as a result of injury or disease. One of the problems related to current neural ...