Improved Current Gain in GaN/SiC Heterojunction Bipolar Transistors by Insertion of Ultra-Thin AlN Layer at Emitter-Junction

Hiroki Miyake; Tsunenobu Kimoto; Jun Suda

doi:10.4028/www.scientific.net/MSF.615-617.979

Paper Titles

High-Breakdown-Voltage GaN Vertical Schottky Barrier Diodes with Field Plate Structure
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Influence of Thermal Annealing on Ohmic Contacts and Device Isolation in AlGaN/GaN Heterostructures
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High Voltage AlGaN/GaN HEMTs Employing a Tapered Field Plate
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Two Broadband GaN MMIC Power Amplifiers for EW Systems
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Improved Current Gain in GaN/SiC Heterojunction Bipolar Transistors by Insertion of Ultra-Thin AlN Layer at Emitter-Junction
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Seeded Growth of AlN on (0001)-Plane 6H-SiC Substrates
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Influence of the N/Al Ratio in the Gas Phase on the Growth of AlN by High Temperature Chemical Vapor Deposition (HTCVD)
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Large Single Crystal Diamond Plates Produced by Microwave Plasma CVD
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Metal Contacts to Boron-Doped Diamond
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HomeMaterials Science ForumMaterials Science Forum Vols. 615-617Improved Current Gain in GaN/SiC Heterojunction...

Improved Current Gain in GaN/SiC Heterojunction Bipolar Transistors by Insertion of Ultra-Thin AlN Layer at Emitter-Junction

Abstract:

GaN/SiC Heterojunction Bipolar Transistors (HBTs) with ultra-thin AlN insertion layers at the n-GaN/p-SiC emitter junction are proposed to improve carrier injection efficiency. The current-voltage characteristics of n-GaN/AlN/p-SiC heterojunctions have exhibited very small reverse leakage and good rectification. The capacitance-voltage measurement have revealed that the conduction band offset between n-GaN and p-SiC has been reduced from -0.74 eV to -0.54 eV by insertion of AlN, indicating that the GaN/AlN/SiC heterojunction may show better electron-injection efficiency. A significantly improved common-base current gain (α~0.2) is obtained for GaN/AlN/SiC HBTs with initial N* pre-irradiation, while it was very low (α~0.001) for GaN/SiC HBTs without AlN layers.