Optical photoreceptors for CMOS neural circuitry.

摘要

The work described in this thesis relates to the design of photoreceptors fabricated in Northern Telecomu27s 3$mu$ CMOS process. The photoreceptor consists of a vertical BJT whose output current is fed to four diode connected MOSFETs. Results of the experiments used to characterize the device both optically and electronically are given. Shortcomings of the device are identified and a modified photoreceptive device has been designed. These photoreceptive devices will be used to provide optical inputs to a neural network. By using optical connections to provide inputs to the chip, data can be sent directly to individual locations on the chip from above. This approach may eventually be used to solve the problems of an analog storage device and of pin-limitations usually associated with the VLSI implementation of neural networks. An architecture for making optimal use of the photoreceptors characteristics is given. This current mode architecture uses the current from the photoreceptor as the input to the network as well as the weights. Source: Masters Abstracts International, Volume: 31-03, page: 1315. Thesis (M.A.Sc.)--University of Windsor (Canada), 1991.