High-performance 4H-SiC p-i-n ultraviolet avalanche photodiodes with large active area

• 来源期刊: 中国光学快报（英文版）
• 年，卷（期）: 2019,（9）
• 页码范围: 1-4
• 页数: 4页
• 语种: 英文
• DOI: 10.3788/COL201917.090401

摘要

Ultraviolet (UV) detectors with large photosensitive areas are more advantageous in low-level UV detection applications.In this Letter,high-performance 4H-SiC p-i-n avalanche photodiodes (APDs) with large active area (800 μm diameter) are reported.With the optimized epitaxial structure and device fabrication process,a high multiplication gain of 1.4 × 106 is obtained for the devices at room temperature,and the dark current is as low as ～10 pA at low reverse voltages.In addition,record external quantum efficiency of 85.5％ at 274 nm is achieved,which is the highest value for the reported SiC APDs.Furthermore,the rejection ratio of UV to visible light reaches about 104.The excellent performance of our devices indicates a tremendous improvement for largearea SiC APD-based UV detectors.Finally,the UV imaging performance of our fabricated 4H-SiC p-i-n APDs is also demonstrated for system-level applications.