A 1/1.57-inch 50Mpixel CMOS Image Sensor With 1.0μm All-Directional Dual Pixel by 0.5μm-Pitch Full-Depth Deep-Trench Isolation Technology

• Main Authors: Jung, Taesub, Fujita, Masato, Cho, Jeongjin, Lee, Kyungduck, Seol, Doosik, An, Sungmin, Lee, Chanhee, Jeong, Youjin, Jung, Minji, Park, Sachoun, Baek, Seungki, Jung, Seungki, Lee, Seunghwan, Yun, Jungbin, Shim, Eun Sub, Han, Heetak, Park, Eunkyung, Sul, Haesick, Kang, Sehyeon, Lee, Kyungho, Ahn, JungChak, Chang, Duckhyun
• Format: Conference Proceeding
• Language: English
• Subjects: CMOS image sensors; Degradation; Dynamic range; Image quality; Image resolution; Isolation technology; Ultraviolet sources
• ISSN: 2376-8606
• DOI: 10.1109/ISSCC42614.2022.9731567

As the strong demand for higher resolution and new functionality is rapidly increasing in the mobile CMOS Image Sensor (CIS) market, we have seen the emergence of: submicron pixels, >200M pixels, fast readout, global shutter, high dynamic range, and phase-detection autofocus (PDAF) [1 - 3]. Among these, PDAF is an essential feature of cutting-edge CIS for accurate autofocus at extremely low-light situations, and dual-pixel technology has been widely used for AF of the entire image area [4]. To implement high pixel resolution in a limited optical size, the pixel size has continued to shrink, and the pixel structure has evolved to maintain high image quality. However, for a dual pixel, integrating two photodiodes (PDs) in one pixel by backside deep trench isolation (BDTI) has technical limitations and causes degradation of image AF performance as well as image quality.