Zhang Fan, Niu Hanben
Key Laboratory of Optoelectronic Devices and Systems of Education Ministry and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
Sensors (Basel). 2016 Jun 29;16(7):999. doi: 10.3390/s16070999.
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.
在本研究中，采用0.5μm混合信号互补金属氧化物半导体（CMOS）工艺实现了一款40×48像素的全局快门CMOS图像传感器，其可调快门时间低至75皮秒。该实现包括在像素阵列中每个p+/n阱光电二极管周围设置连续的接触环，以实现足够的光屏蔽。当用405nm二极管激光器照射时，像素内存储节点的寄生光灵敏度测量值为1/8.5×10⁷，当用650nm二极管激光器照射时为1/1.4×10⁴。像素间距为24μm，每个像素中方形p+/n阱光电二极管的尺寸为每边长7μm，测量得到的随机读出噪声为217 e(-) rms，所设计芯片像素的测量动态范围为5500:1。这里提出的门控CMOS图像传感器（CIS）类型可用于超快速帧相机，以观察不可重复的快速演变现象。
