Optimization of Forward and Reverse Electrical Characteristics of GaN-on-Si Schottky Barrier Diode Through Ladder-Shaped Hybrid Anode Engineering

• Published in: IEEE transactions on electron devices 2022-12, Vol.69 (12), p.1-6
• Main Authors: Yang, Chih Yi, Wu, Jia Hong, Chung, Chin Han, You, Jhan Yi, Yu, Tzu Chieh, Ma, Cheng Jun, Lee, Ching Ting, Ueda, Daisuke, Hsu, Heng Tung, Chang, Edward Yi
• Format: Article
• Language: English
• Subjects: Aluminum gallium nitride; Anodes; Electric potential; Electric variables; Etching; Gallium nitride; Gallium nitrides; gated edge terminated diode; gated ohmic anode; in situ SiN; Leakage current; Optimization; Plasmas; Schottky barrier diode (SBD); Schottky diodes; Voltage; Wide band gap semiconductors
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2022.3217999

In this work, a Schottky Barrier Diode (SBD) with an optimized ladder-shaped hybrid anode (LSHA) is demonstrated. The SBD devices in this work were fabricated on a GaN-on-Si wafer with in situ Si _{\text{3}} N _{{\text{4}}} cap layer. To form the LSHA, a two-step recessed process was implemented. For device optimization, the recess depths of the two recess steps were carefully optimized. Devices with different LSHA recess profiles were fabricated, and their electrical characteristics were evaluated by measuring the forward current, reverse current and breakdown voltage (BV). Optimized device exhibited a low reverse leakage current ( \textit{I}_{\textit{R}} ) of \text{5.66} \times \text{10} ^{-\text{8}} (A/mm), a low turn-on voltage ( \textit{V}_{\textit{T}} ) of 0.315 V, and a BV over 1000 V. In addition, \textit{I}_{\textit{R}} (A/mm) versus \textit{V}_{\textit{T}} ( \textit{V} ) of this work and \textit{R}_{{\text{on}, \text{SP}}} (m \Omega \cdot cm ^{\text{2}} ) versus BV ( \textit{V} ) of this work are benchmarked. We demonstrated the lowest \textit{I}_{\textit{R}} among the GaN SBDs with \textit{V}_{\textit{T}}