New Nonvolatile Memory with RAM Capabilities and Intrinsic Radiation Hardness

摘要

This report describes theoretical and experimental work performed in connection with the development of a new kind of electronic computer memory. The memory is based on a hybrid combination of semiconductor and ferroelectric ceramic elements which uses an anomalous photovoltaic effect found in the ferroelectric ceramics. This memory is a variation on the conventional static or dynamic semiconductor memories in common use. Conventional devices are volatile memories which lose their information content when power to the devices is interrupted. Devices based on the concept, however, are nonvolatile. In some respects they have memory characteristics similar to those of metal nitride oxide semiconductor (MNOS) and floating gate EAPROM (electrically alterable programmable read-only memory) devices. The new photovoltaic ferroelectric-semiconductor, however, can be expected to be superior to the presently available EAPROM devices. This new device will excel in programming time, in the number of possible read/write cycles, and in retention of the encoded memory states. Based on the work, described in this report, the device is also expected to be superior in surviving environmental radiation.