Global Patent Index - EP 0007910 A4

EP 0007910 A4 19801128 - A STRATIFIED CHARGE MEMORY DEVICE.

Title (en)

A STRATIFIED CHARGE MEMORY DEVICE.

Title (de)

MEHRSCHICHTEN-LADUNGSSPEICHERVORRICHTUNG.

Title (fr)

MEMOIRE DE CHARGE STRATIFIEE.

Publication

EP 0007910 A4 19801128 (EN)

Application

EP 79900086 A 19790731

Priority

US 86654178 A 19780103

Abstract (en)

[origin: WO7900474A1] A RAM device employs an array of dual gated transistor memory cells (110) accessed by row and column decoding leads (120R and 120C). A separate P type memory region is provided under the column gate (122C) which acquires holes as a function of the input date during the write cycle, for controlling the flow of an output electron current during the subsequent read cycle. The write holes flow from the substrate (104) into the P memory region to record a "l" when both the row gate (122R) and the column gate are at a low positive potential. The write holes become trapped in the P memory region when the low write voltage on the row gate is replaced by a higher storage voltage. During the read cycle both gates are high, and electron current flow from source to drain along a continuous electron conductive path formed under both gates. The high row voltage causes electron conduction at the surface of the P substrate (104) under the row gate by establishing an N type inversion layer. The high column voltage in combination with the positive charge of the write holes promotes the flow of read electrons under the column gate through a buried N channel (138) adjacent to the P memory region. The read conductive path between the source (114) and drain (116) is formed by the row inversion layer plus the N channel. The stratified charge structure functions as an additional gate beneath the column gate which requires trapped write holes in order to allow electron flow when the row and column gates are activated during read.

IPC 1-7

G11C 11/40; H01L 27/10; H01L 21/82

IPC 8 full level

G11C 11/34 (2006.01); G11C 11/35 (2006.01); H01L 21/822 (2006.01); H01L 27/04 (2006.01); H01L 27/06 (2006.01); H01L 29/78 (2006.01); H10B 12/00 (2023.01)

CPC (source: EP)

G11C 11/35 (2013.01)

Citation (search report)

Designated contracting state (EPC)

FR

DOCDB simple family (publication)

WO 7900474 A1 19790726; EP 0007910 A1 19800206; EP 0007910 A4 19801128; GB 2060997 A 19810507; JP H0160951 B2 19891226; JP S55500033 A 19800124

DOCDB simple family (application)

US 7900001 W 19790102; EP 79900086 A 19790731; GB 7926605 A 19790102; JP 50026879 A 19790102