Title :
Buffer leakage induced pre-breakdown mechanism for AlGaN/GaN HEMTs on Si
Author :
Cen Tang ; Kuang Sheng ; Gang Xie
Author_Institution :
Coll. of Electr. Eng., Zhejiang Univ., Hangzhou, China
Abstract :
An off-state breakdown mechanism of a silicon based AlGaN/GaN High-Electron-Mobility Transistor (HEMT) is proposed. Through physical-based 2D simulations, leakage current model of this breakdown mechanism including AlN/Si interface inversion layer channel and local trap tunneling effect in the buffer layer is proved. Results show that the interfacial inversion based leakage current in the buffer can drastically weaken the VB to 50V for GaN-On-Silicon devices with LGD = 5 μ m thus causing detrimental problems for HEMTs applications. Further design of the GaN-On-Silicon HEMT with an enhanced back barrier layer shows an effective suppression of the leakage current. Simulation result shows a significantly increase of the VB up to 672 V for an optimized structure with the same physical dimensions as the convention device.
Keywords :
III-V semiconductors; aluminium compounds; buffer layers; gallium compounds; high electron mobility transistors; leakage currents; semiconductor device models; silicon; tunnelling; wide band gap semiconductors; AlGaN-GaN; AlN-Si; GaN-on-silicon devices; HEMT; back barrier layer; buffer layer; buffer leakage; detrimental problems; high-electron-mobility transistor; interfacial inversion; inversion layer channel; leakage current; local trap tunneling; off-state breakdown mechanism; pre-breakdown mechanism; through physical-based 2D simulations; Aluminum gallium nitride; Electric fields; Gallium nitride; HEMTs; III-V semiconductor materials; MODFETs; Silicon;
Conference_Titel :
Communications, Circuits and Systems (ICCCAS), 2013 International Conference on
Conference_Location :
Chengdu
Print_ISBN :
978-1-4799-3050-0
DOI :
10.1109/ICCCAS.2013.6765355