公开(公告)号：US3626390A

公开(公告)日：1971-12-07

申请号：US3626390D

申请日：1969-11-13

Applicant: IBM

Inventor： CHANG JOSEPH J ,  HO IRVING TZE ,  VOGL NORBERT G JR ,  WU BEVAN P F

IPC: G11C11/411 ,  H01L21/74 ,  H01L27/07 ,  H03K3/288 ,  G11C11/40

CPC classification number: H03K3/288 ,  G11C11/4116 ,  H01L21/74 ,  H01L27/0755 ,  Y10S148/037 ,  Y10S148/049 ,  Y10S148/085 ,  Y10S148/136

Abstract: A nondestructive read-integrated circuit memory cell consisting of a pair of cross coupled transistors. The junctions between the collectors of the transistors and the intrinsic epitaxial layer is utilized to provide isolation between the transistors. The transistors are formed by a triple-diffusion process wherein the collector region contacts a buried layer of opposite semiconductivity relative to the semiconductivity of the substrate structure. An epitaxial growth being of the same semiconductivity as the buried layer region is utilized as both a resistive material between the input and the buried layer and to form a diode gradient between the epitaxial region and the collector region of the transistors. The buried region forms a diode junction with the collector regions of the transistor to allow a bilevel operation of the memory cell.