CCD Cameras: Dark Current and Noise Analysis

This lecture discusses the various noise sources in CCD cameras, focusing on dark current and its implications. It begins by identifying different types of noise, including photon shot noise and dark current shot noise. The instructor explains how dark current arises from thermal generation of minority carriers and its dependence on temperature, noting that it can double with every 7-8 degree increase. The lecture provides numerical examples of dark current densities in various technologies, highlighting the importance of minimizing dark current for improved performance. The discussion includes the mechanisms of dark current generation, such as band-to-band generation and trap-assisted thermal generation, emphasizing the need for high-quality materials to reduce noise. The instructor also introduces the concept of pinned phase surface inversion to mitigate dark current effects. The lecture concludes with insights into advanced designs that achieve low dark current levels, which are crucial for applications like astrophotography, where long exposure times are necessary.