Lateral AlGaN/GaN Schottky Barrier Diode With Arrayed p-GaN Islands Termination
Haiyong Wang, Wei Mao, Cui Yang, Jiabo Chen, Shenglei Zhao, Ming Du, Xiaofei Wang, Xuefeng Zheng, Chong Wang, Chunfu Zhang, Jincheng Zhang, Yue Hao
Abstract
A lateral Schottky barrier diode (SBD) on p-GaN/AlGaN/GaN heterostructure with arrayed p-GaN islands termination (API-SBD) is proposed and investigated in this work. On the basis of the unique design approach, API-SBD presents a reduced reverse leakage current ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{R}$ </tex-math></inline-formula> ) with one order of magnitude lower than that of counterpart SBD with the only recessed anode (R-SBD). The turn-on voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> ) of API-SBD is nearly the same as that of R-SBD, which shows an effective improvement of the tradeoff between <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{R}$ </tex-math></inline-formula> . The breakdown voltage (BV) of API-SBD is obviously improved due to the introduction of p-GaN islands termination by shielding the high electric field from the Schottky junction. In addition, the capacitance of API-SBD is approximately a half of that of R-SBD. The fabricated API-SBD with a 15- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> anode–cathode distance exhibits a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> of ~0.59 V, an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{R}$ </tex-math></inline-formula> of ~10 nA/mm (at −100 V), and a BV of 1070 V (at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${1}~\mu \text{A}$ </tex-math></inline-formula> /mm). It is worth noting that the fabrication process of API-SBD is fully compatible with that of p-GaN HEMT, which is helpful for the monolithic integration.