Improvement of switching characteristics by substrate bias in AlGaN/AlN/GaN heterostructure field ef

• 作 者: 杨铭 林兆军 赵景涛 王玉堂 李志远 吕元杰 冯志红
• 机 构: School of Physics, Shandong University,National Key Laboratory of Application Specific Integrated Ci
• 出 处: Chinese Physics B
• 发表日期: 2015年11期
• 关键词: switching AlGaN swing drain attributed applying nucleation leakage sapphire semi

A simple and effective approach to improve the switching characteristics of Al Ga N/Al N/Ga N heterostructure field effect transistors(HFETs) by applying a voltage bias on the substrate is presented. With the increase of the substrate bias,the OFF-state drain current is much reduced and the ON-state current keeps constant. Both the ON/OFF current ratio and the subthreshold swing are demonstrated to be greatly improved. With the thinned substrate, the improvement of the switching characteristics with the substrate bias is found to be even greater. The above improvements of the switching characteristics are attributed to the interaction between the substrate bias induced electrical field and the bulk traps in the Ga N buffer layer, which reduces the conductivity of the Ga N buffer layer.

A simple and effective approach to improve the switching characteristics of Al Ga N / Al N / Ga N heterostructure field effect transistors (HFETs) by applying a voltage bias on the substrate is presented. With the increase of the substrate bias, the OFF-state Both the ON / OFF current ratio and the subthreshold swing are demonstrated to be greatly improved. With the thinned substrate, the improvement of the switching characteristics with the substrate bias is found to be even greater. The above improvements of the switching characteristics are attributed to the interaction between the substrate bias induced electrical field and the bulk traps in the Ga N buffer layer, which reduces the conductivity of the Ga N buffer layer.