[22p-P05-1~3] 3.12 Semiconductor optical devices (formerly 3.13)

[22p-P05-2] Realization of high sensitivity imaging in charge multiplication film bonded imaging device using single crystal gallium oxide substrate as hole injection blocking layer

〇Keitada Mineo¹, Shigeyuki Imura¹, Kazunori Miyakawa¹, Satoshi Aihara¹, Mutsumi Sugiyama², Masakazu Nanba¹ (1.NHK STRL, 2.Tokyo Univ. Sci.)

Keywords:gallium oxide, Image sensor, Selenium

We have studied high-sensitivity imaging devices using the avalanche multiplication phenomenon. We have succeeded in obtaining charge-multiplying images with a structure consisting of a CMOS circuit and a sapphire substrate bonded with a crystalline selenium photoconversion film. However, reduction of crystal defects was a problem in achieving high multiplication factor. In this study, we have investigated a new configuration using a single-crystal gallium oxide substrate instead of a polycrystalline gallium oxide thin film as a hole injection blocking layer. As a result, high-sensitivity imaging with a multiplication factor of 3.5 and a dark current of 1.25 nA/cm² was successfully obtained.