Low-Noise Electronic Imaging with Double-Gate FETs and Charge-Modulation Devices

Abstract

Virtually complete charge transfer can be achieved with charge coupled devices (CCDs) in the buried channel configuration because the buried channel CCD introduces no transfer noise. However, conventional charge detectors incorporated into CCDs have a comparably large noise, which consists of thermal noise and 1/f noise from MOS transistor in the output charge detectors. Highly sensitive double gate charge detectors are presented in this chapter to show the ability of CCD low noise performance of less than 1 electron rms at room temperature and at video frequency. The concept of double gate charge detection can alternatively be implemented in a pixel incorporating a charge modulation device (CMD), reaching also an effective readout noise level of less than 1 electron rms. In practice, the CMD shows larger fixed-pattern noise behavior, necessitating supplementary signal processing efforts. Virtually complete charge transfer can be achieved with charge coupled devices (CCDs) in the buried channel configuration because the buried channel CCD introduces no transfer noise. However, conventional charge detectors incorporated into CCDs have a comparably large noise, which consists of thermal noise and 1/f noise from MOS transistor in the output charge detectors. Highly sensitive double gate charge detectors are presented in this chapter to show the ability of CCD low noise performance of less than 1 electron rms at room temperature and at video frequency. The concept of double gate charge detection can alternatively be implemented in a pixel incorporating a charge modulation device (CMD), reaching also an effective readout noise level of less than 1 electron rms. In practice, the CMD shows larger fixed-pattern noise behavior, necessitating supplementary signal processing efforts.