Numerical Analysis of Forward-Current/Voltage Characteristics of Vertical GaN Schottky-Barrier Diodes and p-n Diodes on Free-Standing GaN Substrates

• Published in: IEEE transactions on electron devices Vol. 58; no. 7; pp. 1979 - 1985
• Main Authors: Mochizuki, K, Mishima, T, Terano, A, Kaneda, N, Ishigaki, T, Tsuchiya, T
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-07-2011; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Anodes; Applied sciences; Carrier lifetime; Compound structure devices; Current measurement; Devices; Diodes; Electric potential; Electrical engineering. Electrical power engineering; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; Gallium compounds; Gallium nitride; Gallium nitrides; Gold; Mathematical models; Numerical analysis; Power electronics, power supplies; power semiconductor devices; Schottky diodes; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; simulation; Substrates; Voltage; Binary compound; Voltage current curve; simulation; Durability; p n junction; Power electronics; Numerical method; Gallium nitride; III-V compound; Gallium compound; Dislocation; Thermionic emission; Carrier lifetime; Power device; Electron mobility; power semiconductor devices; Electron density; Schottky barrier diode; Electron drift; Reliability; Current density; Gallium compounds; Drift mobility
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2011.2145380

Forward-current-density J F /forward-voltage V F characteristics of vertical gallium-nitride (GaN) Schottky-barrier diodes (SBDs) and p-n diodes on free-standing GaN substrates were computationally, as well as experimentally, investigated. Based on the thermionic emission model, electron-drift mobility μ n was used as a parameter to fit the J F - V F characteristics of both reported and fabricated GaN SBDs. At 300 K, μ n was fitted to be 600 cm 2 /V ·s when electron concentration n was 1 × 10 16 cm -3 and 750 cm 2 /V ·s when n was 5 ×10 15 cm -3 . Accordingly, the theoretical μ n - n curve for a carrier compensation ratio of 0.90 was applied in the case of n-GaN layers on GaN substrates. With respect to GaN p-n diodes, the reported J F - V F characteristics were successfully fitted with dislocation-mediated carrier lifetimes in the high-injection region and with Shockley-Read-Hall lifetimes in the generation-recombination current region.