大动态高灵敏1024×1024 EMCCD研制

Development of Large Dynamic and High Sensitivity 1024×1024 EMCCD

摘要:

随着硅材料质量的提升和半导体工艺技术的发展,低温制冷下电荷耦合器件(CCD)的暗电流已经可以忽略,此时放大器成了主要的噪声源,限制了对微弱信号的检测。采用电子倍增技术,通过对电荷包在进入输出节点前进行放大,可有效抑制放大器的噪声。然而,电荷包放大后容易饱和,会限制器件的动态范围。本研究采用浮置栅放大器对电荷包进行无损检测。根据检测结果,大的电荷包直接输出,小的电荷包通过电子倍增放大后再输出,获得高灵敏度的同时兼顾了大的动态范围。根据实际测试结构,在10-4Lx光照下得到了良好的微光成像效果,同时动态范围可达15万倍。

Abstract:

With the improvement of silicon material quality and the development of semiconductor process technology, the dark current of CCD (Charge-Coupled Device) under low-temperature refrigeration can be neglected. At this time, the amplifier becomes the main noise source, which limits the detection of weak signals. By using the electronic multiplication (EM) technology to amplify the charge packet before it enters the output stage, the noise of the amplifier can be effectively suppressed. However, the charge packets are easily saturated after amplification, which will limit the dynamic range of the device. In this study, the floating gate amplifier performed nondestructive detection on the charge packets. According to the detection results, the amplifier outputs the large charge packets directly, while the small charge packets are amplified by electron multiplication and then output, thus obtaining high sensitivity and large dynamic range. According to the actual test structure, good micro-light imaging is obtained under 10-4Lx illumination, while the dynamic range was up to 150,000 times.