High sensitivity image sensor overlaid with thin-film crystalline-selenium-based heterojunction photodiode

We have developed a stacked image sensor based on a thin-film crystalline selenium (c-Se) heterojunction photodiode. Uniform c-Se-based photodiodes laminated on complementary metal-oxide-semiconductor circuits were fabricated by tellurium-diffused crystallization. We herein present the first high-resolution images obtained with such a device. Furthermore, the dark current was significantly decreased by using an n-type wide-band-gap gallium oxide (Ga₂O₃) layer with a high hole-injection barrier.