Investigation of Hafnium Dioxide MIS Structure Prepared by RF Sputtering System and Its Application

• Main Authors: Mien-Ho Lin, 林勉和
• Other Authors: Chun-Hsing Liu,Ping-Chuan Chang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/92750363658725265432

碩士 === 南榮技術學院 === 工程科技研究所碩士班 === 98 === This study is the investigation of the optical and electrical properties of hafnium dioxide (HfO2) using MIS structure prepared by RF sputtering system. The excellent electric and optical properties of hafnium dioxide are useful for photodetectors. The samples used in this experiment were epitaxially grown by metal organic chemical vapor deposition system (MOCVD) on 2-inch c-face (0001) sapphire substrates. The use of InGaN thin film offers the possibility of shifting the detection edge from the UV to the VIS (and even the IR) by changing the indium composition in the InGaN layers. PDs in this study were designed to be sensitive in the blue wavelength range with 0.1 indium composition. In order to increase the barrier schottky height, we utilize RF sputtering system to grow a layer of HfO2 on the top of InGaN. This study can be divided into two parts. The first part of researches includes the optical and electric characteristics of hafnium dioxide material. Experimental results show that the hafnium dioxide thin film with the thickness of 40nm has the average transmittance of exceed 80% in the wavelength ranging from 380nm to 700nm. In the electrical characteristics, the dark current with the 5V applied bias was about 1.54×10-8A. The second part illustrates that the samples with the same thickness of 40nm were annealed by rapid thermal and furnace. Experimental results demonstrate that the hafnium dioxide thin film with the same thickness of 40nm and the annealing temperature of 700℃ has the average transmittance of exceed 80% in the wavelength ranging from 380nm to 700nm. A minimum dark current with 5V applied bias was 1.3×10-10A. According to the above results, the hafnium dioxide thin film using furnace annealing obtains lower dark current. Therefore, the hafnium dioxide MIS structure prepared by RF sputtering system and annealed by furnace can be applied in the fabrication of photodetectors. Keywords: HfO2, photodetector, rapid thermal annealing.