Electric field modulation technique for high-voltage AlGaN/GaN Schottky barrier diodes  

作　　者：汤岑 谢刚 张丽 郭清 汪涛 盛况 

机构地区：[1]College of Electrical Engineering,Zhejiang University [2]Division of Energy,High Technology Research and Development Center,the Ministry of Science and Technology

出　　处：《Chinese Physics B》2013年第10期406-411,共6页中国物理B（英文版）

基　　金：Project supported by the Science Foundation of the Ministry of Education of China (Grant No.20100101110056);the Natural Science Foundation of Zhejiang Province of China for Distinguished Young Scholars (Grant No.R1100468)

摘　　要：A novel structure of AIGaN/GaN Schottky barrier diode （SBD） featuring electric field optimization techniques of anode-connected-field-plate （AFP） and magnesium-doped p-type buried layer under the two-dimensional electron gas （2DEG） channel is proposed. In comparison with conventional A1GaN/GaN SBDs, the magnesium-doped p-type buried layer in the proposed structure can provide holes that can help to deplete the surface 2DEG. As a result, surface field strength around the electrode edges is significantly suppressed and the electric field along the channel is distributed more evenly. Through 2D numerical analysis, the AFP parameters （field plate length, LAFP, and field plate height, TAFP） and p-type buried layer parameters （p-type layer concentration, Np, and p-type layer thickness, Tp） are optimized to achieve a three-equal-peak surface channel field distribution under exact charge balance conditions. A novel structure with a total drift region length of 10.5 μm and a magnesium-doped p-type concentration of 1 × 10^17 cm 3 achieves a high breakdown voltage （VB） of 1.8 kV, showing 5 times improvement compared with the conventional SBD with the same device dimension.A novel structure of AIGaN/GaN Schottky barrier diode （SBD） featuring electric field optimization techniques of anode-connected-field-plate （AFP） and magnesium-doped p-type buried layer under the two-dimensional electron gas （2DEG） channel is proposed. In comparison with conventional A1GaN/GaN SBDs, the magnesium-doped p-type buried layer in the proposed structure can provide holes that can help to deplete the surface 2DEG. As a result, surface field strength around the electrode edges is significantly suppressed and the electric field along the channel is distributed more evenly. Through 2D numerical analysis, the AFP parameters （field plate length, LAFP, and field plate height, TAFP） and p-type buried layer parameters （p-type layer concentration, Np, and p-type layer thickness, Tp） are optimized to achieve a three-equal-peak surface channel field distribution under exact charge balance conditions. A novel structure with a total drift region length of 10.5 μm and a magnesium-doped p-type concentration of 1 × 10^17 cm 3 achieves a high breakdown voltage （VB） of 1.8 kV, showing 5 times improvement compared with the conventional SBD with the same device dimension.

关 键 词：gallium nitride high voltage SBD field plate magnesium buried layer 

分 类 号：TN311.7[电子电信—物理电子学] TN304.23