Development of an Accelerated Step-Stress Methodology for the Evaluation of the Stability of GaN-on-Si Power MIS-HEMTs

• Main Authors: Zhang, Jin-Ming, 章晉銘
• Other Authors: Sze, Simon
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/nhcnda

碩士 === 國立交通大學 === 電子研究所 === 106 === By means of an accelerated step-stress methodology, the stability of GaN MIS-HEMTs was evaluated. We first studied the off-state stress condition and the reverse gate bias condition by using the constant stress measurement. Then, we utilized the step-stress measurement to monitor the stress leakage current, threshold voltage and on-resistance variation. The measurements were made under : (1) the off-state step-stress condition to study the real operation of devices. (2) the reverse gate step-stress condition to study the capability and endurance of the films below the gate. (3) the back-gating step-stress condition to study the influence of the epitaxial layer. Comparing the two methodologies, we found an interesting phenomenon under off-state step-stress condition. Based on the evaluation of the activation energy, the shallow traps are responsible for the phenomenon. In addition, the increase of the bulk leakage current is due to the traps of the complexes of gallium vacancies and oxygen or/and nitrogen vacancies.