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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 18 of 18 for “"Schottky contact"”.
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Investigation of Surface States and Device Surface Charging in Nitride Materials Using Scanning Kelvin Probe Microscopy
… after turning off a reverse bias to the Schottky contact of a GaN Schottky diode as well as an AlGaN/GaN Hetero-junction Field Effect Transistor (HFET) show an increase of band bending near the Schottky contact edge. For an applied reverse bias of 4 V, about 0.5 eV increase of band …
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Parallel Fabrication and Transport Properties of Carbon Nanotube Single Electron Transistors
… on SWNT. Two different techniques: i) metal-SWNT Schottky contact, and ii) mechanical templating of SWNTs were used for tunnel barrier creation. Low temperature (4.2K) transport measurement of 100 nm long metal-SWNT Schottky contact devices show that 93% of the devices with contact resistance (RT) …
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Fabrication and characterization of AIGaN/GaN HEMTs
… processing procedure for the formation of ohmic contact using Ti/Al/Pd/Au, and Schottky contact using Pd/Au on AlGaN/GaN HEMT has been developed. A specific contact resistance of 1.08 x 10-7 W cm2 was achieved and an Schottky barrier height of 1.12eV was reached. Large dimension AlGaN/GaN HEMT …
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Measurement and Modeling of Blocking Contacts for Cadmium Telluride Gamma Ray Detectors
… This thesis characterizes and models two unique Schottky devices: one with an argon ion sputter etch before Schottky contact deposition and one without. Analysis of current versus voltage characteristics shows that thermionic emission alone does not describe these devices. This analysis points to …
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AFM and C-AFM Studies of GaN Films
… all similar. Local I-V spectra of the tip-sample Schottky contact could be grouped according to three major types: low leakage, high leakage, and "p-type". The highest quality samples with low leakage were usually grown at moderate temperatures (~650°C). For such samples, localized leakage only …
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Modeling of Joule heating and thermoelectric transport in thin film silicon for SJEM measurement
… of 1019 cm-3 and 1018 cm-3. PtSi or NiSi Ohmic contacts are formed on the devices and thermoelectric behaviors are analyzed in conditions either under simultaneous DC and AC excitations, or AC only excitations. The simulation results show that thermoelectric contribution in heating increases …
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Self-Aligned Fabrication of Nanogap Based Zinc Oxide Nanowire Schottky Devices Using Adhesion Lithography
… advantages can only be realized if high quality contacts can be made to the nanowires, which require expensive techniques such as electron beam lithography. To fabricate nano devices on a large scale, this work focuses on combining bottom-up nanowire growth with nanogap fabrication using adhesion …
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Development of the Visible Light Photon Counter for Applications in Quantum Information Science
… the incident photons are absorbed within the top contact of the device, whereas, in the infrared, Si is practically transparent. A number of applications in quantum information science would benefit from use of the VLPC if the QE was improved in the ultraviolet (e.g., state detection of trapped …
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Modelling of Multichannel GaN Transistors
… p-GaN gate HEMT, this thesis compares the gate Schottky contact and ohmic contact, evaluating their reliability and the influence of the field plate on device performance. Further research extends to multichannel HEMTs, establishing a multichannel simulation platform to investigate the …
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Synthesis and characterization of TiO2 nanotube Schottky diodes
… rectifying metal-semiconductor interface, or Schottky junction, throughout an ordered array of semiconducting nanotubes. The atomic layer deposition (ALD) technique offers a precise, conformal growth mechanism and was used to deposit a continuous platinum (Pt) Schottky contact throughout the …
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Integration of aligned arrays of single-walled carbon nanotubes in electronic devices
… unlike in networks of SWNTs. Hence, tube/tube contacts, which limit the transport in SWNT networks due to tunneling barriers or electrostatic screening at the contacts to prevent effective gate modulation at those specific points, are absent. Nonetheless, challenges still remain for these …
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Diamond Schottky barrier diodes
… results exhibited by silicon carbide (SiC) Schottky batTier diodes (SBDs), commercially available since 2001, showed the potential of wide band gap semiconductors for replacing silicon (Si) in the range of medium to high voltage applications, where high frequency operation is required. With …
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Charakterisierung und Optimierung von (Al, Ga)N-basierten UV-Photodetektoren
… The focus was on the realization of Schottky-type MSM PD suitable for photodetection below wavelengths of 300 nm with a high external quantum efficiency (EQE). First, experimental and simulated results were combined to give a detailed study of the performance of top- and …
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OPTICAL CHARACTERIZATION OF WIDE ENERGY AGP GROUP III-NITRIDE SEMICONDUCTORS
… spectra and findings. Photoreflectance (PR) and contactless electroreflectance (CER) were employed to study the undoped GaN, n-type GaN, Au-Schottky contacts on GaN, and piezoelectric effects in AIGaN/InGaN/GaN heterostructures. With the assistance of the PV spectra, we found that both the free …
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Electronic structure, defect formation and passivation of 2D materials
… theory (DFT) which provides robust results. The Schottky barrier height (SBH) is calculated for hexagonal nitrides. The SBH has a linear relationship with metal work function but the slope does not always equal because Fermi level pinning (FLP) arises. The chemical trend of FLP is investigated. …
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Reliability Characterisation of III-Nitrides Based Devices for Technology Development
… degradation (e.g. access resistance of contacts, and gate leakage current) persist to be limiting reliability factors. The mechanisms contributing towards performance and reliability degradation of AlGaN/GaN HEMTs, namely self-heating, charge trapping and strain, are required to be …
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Graphene Heterostructures with Wide Bandgap Semiconductors
… applicazioni in dispositivi (fra cui il diodo Schottky Gr/SiC con barriera modulata da un elettrodo di gate e un transistor ad elettroni caldi costituito da eterostrutture Gr/AlGaN/GaN) e sono stati stimati i relativi possibili vantaggi rispetto agli equivalenti dispositivi su silicio.
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Electron Injection-induced Effects In Iii-nitrides: Physics And Applications
… electrons into commercially built p-i-n and Schottky barrier photodetectors. Up to an order of magnitude increase in the peak (360 nm) responsivity was observed. The enhanced photoresponse lasted for over four weeks and was attributed to an electron injection-induced increase of L[subscript …