Rotating MNOS disk memory device

This paper presents a new recording and reproducing system using a disk-type charging medium, i.e., a rotating MNOS disk memory device, which consists of a single stationary 'metal' electrode and an 'NOS' disk rotating in contact with it. This is capable of reading information immediately after writing it, and also capable of easily rewriting part or all of the written information without aid of any physical or chemical processing, by overlay-recording new information over the old, as well as permitting the recording of information at a very high density. This type of electrically erasable memory has the potential for storing a bit of information in an area of less than 1 µm². Using a prototype disk made of a 3-in-diameter silicon wafer, we recently demonstrated a single-field TV memory.