Photodetectors: Photodiodes and photoconductors

This lecture covers the operation and characteristics of photodiodes and photoconductors, focusing on their internal junctions, controlled carrier collection, and device structures. It discusses the importance of p-i-n and Schottky diodes, as well as the differences in linearity, dark current, and carrier transport. The lecture also explores the necessity of a p-i-n structure for disordered semiconductors, the spectral sensitivity of photodiodes, and the fabrication processes for CIGS solar cells. Additionally, it delves into the requirements, materials, and spectral absorption of photodetectors, emphasizing the importance of band diagrams and the challenges faced in forming p-n junctions and hetero-junctions.