Investigations of AlGaN/GaN HFETs with High-k TiO2 by Using Ultrasonic Spray Pyrolysis Deposition Technique
| Autor: | Cheng-Long Yang, 楊政龍 |
|---|---|
| Rok vydání: | 2014 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 102 In this thesis, the conventional schottky gate, surface passivated and metal-oxide-semiconductor AlGaN/GaN heterostructure field-fffect transistors (HFETs) were studied by using ultrasonic spray pyrolysis deposition technique are presented. In order to solve the issue of higher gate leakage current and surface leakage current in scaled devices, we use high dielectric materials such as titanium dioxide as a surface passivated and gate dielectric layer and compare them with conventional HFETs structure. The optimizations of the experimental conditions of surface passivated and gate dielectric layer structure HFETs were studied in direct current characteristics: maximum saturation drain current density ID, max (511 mA/mm, 571 mA/mm and 650 mA/mm), maximum extrinsic transconductance gm, max (110 mS/mm, 125 mS/mm and 107 mS/mm), maximum current density IDSS0 (342 mA/mm, 377 mA/mm and 384 mA/mm), Ig (2.27 × 10-1 mA/mm, 2.71 × 10-3 mA/mm and 1.22 × 10-4), two terminal gate-drain breakdown voltage BVGD (-104 V, -130 V and -155 V), three terminal drain-source breakdown voltage BVDS (94 V, 131 V and 139 V), respectively. From the experiment results, the performance enhancement of TiO2 surface passivated HFET and TiO2 metal-oxide-semiconductor HFET (MOS-HFET) structure process successfully improve DC characteristics by using ultrasonic spray pyrolysis deposition technique. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|