A little "BIT" on charge coupled devices

A survey of charge coupled devices (CCD´s) which considers past experience, present understanding and possible future realizations is presented. Effort and interest in CCD´s have experienced rapid growth in the last two years, primarily because of the existing broad base of MOS technology used to fabricate the structures. As a result, the progression from the initial idea to practical, functioning devices has been unusually fast. The understanding of the device physics has also proceeded quickly, and analysis indicates that devices capable of high quality performance are feasible with existing technology. A number of such structures including linear and area imaging devices and analog and digital shift registers have been made by several different locations. Study of the experimental results suggests that in the future not only more ambitious versions of these devices will be successfully constructed but also related structures, such as high-speed memories or logic, may well emerge as more effective realizations of charge coupling are developed.