Design of GaAs charge coupled devices
Abstract
The technology of Charge Coupled Devices (CCD's) in silicon has matured to the point where application of these devices in imagers has become widespread. Certain applications which are conceptually well suited to CCD implementation, such as high speed signal processing and fast response imagers, are difficult to obtain with silicon CCD technology. These limitations are direct consequences of silicon material properties, such as low electron mobility and high intrinsic carrier concentration. The higher electron mobility and wider bandgap of GaAs compared to silicon make GaAs a potentially more desirable material for high speed CCD technology. Operation of GaAs CCD's up to 4.2 GHz has been reported. Significant performance advantages can result from the wider bandgap (1.9 eV) of GaAs and its related alloys. Small increases in bandgap result in orders of magnitude reductions in intrinsic carrier concentration and correspondingly low dark current. This low dark current in GaAs can potentially lead to imaging devices with room temperature charge integration/storage times of hours rather than fractions of a second. The proposed project, to be completed in three phases, is to design a GaAs CCD imager for high speed transient capture.
- Publication:
-
Final Report California Univ
- Pub Date:
- 1990
- Bibcode:
- 1990ucd..rept.....U
- Keywords:
-
- Charge Coupled Devices;
- Design Analysis;
- Fabrication;
- Gallium Arsenides;
- Computer Graphics;
- Computerized Simulation;
- Current Density;
- Electron Transfer;
- Electrostatics;
- Image Processing;
- Mobility;
- Optimization;
- Poisson Equation;
- Reliability;
- Surges;
- Solid-State Physics