title: A 75-ps Gated CMOS Image Sensor with Low Parasitic Light Sensitivity.
abstract: In this study, a 40 × 48 pixel global shutter complementary metal-oxide-semiconductor (CMOS) image sensor with an adjustable shutter time as low as 75 ps was implemented using a 0.5-μm mixed-signal CMOS process. The implementation consisted of a continuous contact ring around each p+/n-well photodiode in the pixel array in order to apply sufficient light shielding. The parasitic light sensitivity of the in-pixel storage node was measured to be 1/8.5 × 10⁷ when illuminated by a 405-nm diode laser and 1/1.4 × 10⁴ when illuminated by a 650-nm diode laser. The pixel pitch was 24 μm, the size of the square p+/n-well photodiode in each pixel was 7 μm per side, the measured random readout noise was 217 e(-) rms, and the measured dynamic range of the pixel of the designed chip was 5500:1. The type of gated CMOS image sensor (CIS) that is proposed here can be used in ultra-fast framing cameras to observe non-repeatable fast-evolving phenomena.
authors.affiliation: Key Laboratory of Optoelectronic Devices and Systems of Education Ministry and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China. zhangfan3@email.szu.edu.cn.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Optoelectronic Devices and Systems of Education Ministry and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China. hbniu@szu.edu.cn.
authors.forename: Hanben
authors.initials: H
authors.lastname: Niu
keywords: CMOS image sensor (CIS); framing camera; gated imager; high shutter efficiency; low parasitic light sensitivity; snapshot imager; ultra-fast global shutter