Browsing by Author "Bıyıklı, Necmi"
Now showing items 1-20 of 125
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45 GHz bandwidth-efficiency resonant cavity enhanced ITO-Schottky photodiodes
(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
(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 ... -
A 60 GHz beam-steering reconfigurable antenna
(IEEE, 2016)We present the design, microfabrication, and characterization of a multifunctional reconfigurable antenna (MRA) with beam steering capability operating at 60 GHz band (59-66 GHz). The MRA provides 3 different beam directions ... -
AlGaN-based high-performance metal-semiconductor-metal photodetectors
(Elsevier BV, 2007-10)Design, structure growth, fabrication, and characterization of high performance AlGaN-based metal–semiconductor–metal (MSM) photodetectors (PD) are reported. By incorporating AlN nucleation and buffer layers, the leakage ... -
Amorphous to tetragonal zirconia anostructures and evolution of valence and core regions
(American Chemical Society, 2015)In this report, we study the evolution of valence band (VB) structure during a controlled amorphous to tetragonal transformation of ZrO2 core-shell nanostructures fabricated from electrospun nanofiber template (at 130, ... -
Area-selective atomic layer deposition using an inductively coupled plasma polymerized fluorocarbon layer: A case study for metal oxides
(American Chemical Society, 2016)Area-selective atomic layer deposition (AS-ALD) has attracted immense attention in recent years for self-aligned accurate pattern placement with subnanometer thickness control. Here, we demonstrate a methodology to achieve ... -
Atomic layer deposition of GaN at low temperatures
(A I P Publishing LLC, 2012)The authors report on the self-limiting growth of GaN thin films at low temperatures. Films were deposited on Si substrates by plasma-enhanced atomic layer deposition using trimethylgallium (TMG) and ammonia (NH 3) as the ... -
Atomic layer deposition: an enabling technology for the growth of functional nanoscale semiconductors
(Institute of Physics Publishing, 2017)In this paper, we present the progress in the growth of nanoscale semiconductors grown via atomic layer deposition (ALD). After the adoption by semiconductor chip industry, ALD became a widespread tool to grow functional ... -
Au/TiO2 nanorod-based Schottky-type UV photodetectors
(Wiley, 2012-10-12)TiO2 nanorods (NRs) were synthesized on fluorine-doped tin oxide (FTO) pre-coated glass substrates using hydrothermal growth technique. Scanning electron microscopy studies have revealed the formation of vertically-aligned ... -
A baseball-bat-like CdTe/TiO2 nanorods-based heterojunction core–shell solar cell
(Elsevier, 2013)Rutile TiO2 nanorods on fluorine-doped thin oxide glass substrates via the hydrothermal technique were synthesized and decorated with a sputtered CdTe layer to fabricate a core-shell type n-TiO2/p-CdTe solar cell. Absorbance ... -
Boundary element method for optical force calibration in microfluidic dual-beam optical trap
(SPIE, 2015)The potential use of optical forces in microfluidic environment enables highly selective bio-particle manipulation. Manipulation could be accomplished via trapping or pushing a particle due to optical field. Empirical ... -
Broadband high-gain 60 GHz antenna array
(IEEE, 2016)The design, fabrication and characterization of a 2×8 patch antenna array operating in the IEEE 802.11ad frequency band (57-66 GHz) is presented. The design is based on two-layer structures, where the radiating patches ... -
Capacitance-conductance characteristics of Au/Ti/Al2O3/n-GaAs structures with very thin Al2O3 interfacial layer
(Institute of Physics Publishing, 2015)High-k Al2O3 with metallic oxide thickness of about 3 nmon n-type GaAs substrate has been deposited by the atomic layer deposition (ALD) technique. Thus, it has been formed the Au-Ti/Al2O3/n-GaAs MIS structures. It has ... -
Capacitance-conductance-current-voltage characteristics of atomic layer deposited Au/Ti/Al2O3/n-GaAs MIS structures
(Elsevier Ltd, 2015)We have studied the admittance and current–voltage characteristics of the Au/Ti/Al2O3/nGaAs structure. The Al2O3 layer of about 5 nm was formed on the n-GaAs by atomic layer deposition. The barrier height (BH) and ideality ... -
CO2 laser polishing of microfluidic channels fabricated by femtosecond laser assisted carving
(Institute of Physics Publishing, 2016-10)In this study, we investigate the effects of CO2 laser polishing on microscopic structures fabricated by femtosecond laser assisted carving (FLAC). FLAC is the peripheral laser irradiation of 2.5D structures suitable for ... -
CO2 polishing of femtosecond laser micromachined microfluidic channels
(Optical Society of America, 2016)The CO2 polishing of femtosecond laser micromachined channels is studied. The surface quality before and after polishing is observed with naked eye and optical microscope. The method improves imaging of microspheres. -
Comparison of trimethylgallium and triethylgallium as "ga" source materials for the growth of ultrathin GaN films on Si (100) substrates via hollow-cathode plasma-assisted atomic layer deposition
(AVS Science and Technology Society, 2016-02)GaN films grown by hollow cathode plasma-assisted atomic layer deposition using trimethylgallium (TMG) and triethylgallium (TEG) as gallium precursors are compared. Optimized and saturated TMG/TEG pulse widths were used ... -
Complementary spiral resonators for ultrawideband suppression of simultaneous switching noise in high-speed circuits
(Electromagnetics Academy, 2014)In this paper, a novel concept for ultra-wideband simultaneous switching noise (SSN) mitigation in high-speed printed circuit boards (PCBs) is proposed. Using complementary spiral resonators (CSRs) etched on only a single ... -
Current transport mechanisms in plasma-enhanced atomic layer deposited AlN thin films
(A I P Publishing LLC, 2015)Here, we report on the current transport mechanisms in AlN thin films deposited at a low temperature (i.e., 200°C) on p-type Si substrates by plasma-enhanced atomic layer deposition. Structural characterization of the ... -
Design, fabrication and characterization of high performance resonant cavity enhanced photodetectors
(Bilkent University, 1998)
