Improving Breakdown Voltage for double-Channel AIGaN/GaN HEMTs with Slant Field-Plate

• Main Authors: Kuo-Nan Zhuang, 莊國男
• Other Authors: Yang-Hua Chang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/79002115331023624529

碩士 === 國立雲林科技大學 === 電子工程系 === 103 === AlGaN/GaN high electron mobility transistor short for HEMTs because of its excellent material properties, is very suitable for high temperature and high power high frequency. According to the study pointed out that the improving breakdown voltage can increase the power of device, therefore, how to improve the breakdown voltage of device is the important direction to this paper.The paper by dual-channel AlGaN/GaN HEMTs itself has two carrier channels and has a high saturation current, and for improving the performance of the device breakdown voltage, so that dual channel element having high breakdown voltage is more suitable for high output power components.Research indicates that leakage current of components is an important factor in the device that is why the breakdown voltage drop, there are three major leakage path, the first due to the high electric field peak of gate edge through impact ionization effect and cause gate leakage current, the second with the ends of the drain-source bias pressure, so that in the channel off, through tunneling effect causes the drain-source leakage current, The third because the drain bias voltage is too high and straight through the substrate caused the entire vertical leakage current. The research is often used to enhance the breakdown voltage by using the gate field plates and doped layers in two ways, namely to reduce the high electric field peaks of gate edge and tunneling effect of the channel drop leakage current, and thus enhance the breakdown voltage of the device. In this paper, use Sentaurus TCAD semiconductor simulation software to simulate AlGaN / GaN HEMT device characteristics, first introduced the physical model that we use in simulation and through the analog current and measurement of electrical current matching to ensure the accuracy of the physical model that we simulation. Then improvement the breakdown voltage for dual-channel device.First, compare the general gate field plate and the gate slant field plate for enhancing the breakdown voltage on the dual-channel device, and then use the gate slant field plate with optimize their gate length structure to improve the breakdown voltage of components.Next, using the doping layer, and discussed in greater thickness and doping of different doping concentration, optimum design of the doped layer to improve the breakdown voltage of components.Finally, combine the optimized slant field plate structure and design of the optimized doping concentration of the doped layer structure, to improve the breakdown voltage characteristics of components,let the components has a high breakdown voltage characteristics, designed to effectively improve the breakdown voltage of the structure components.