Patent ID: 6044011
Filing Date: 2000-03-28
Classification: G11C,H01L,Y10S

Abstract:
A memory cell, comprising:first and second access terminals;first and second data nodes;first and second supply terminals;a read-write enable terminal;a first semiconductor region having a first doping concentration of a first conductivity and coupled to the first supply terminal;a second semiconductor region having a second doping concentration of the first conductivity and coupled to the first supply terminal;a first cell transistor coupled to the second supply terminal and to the first data node and having a control terminal coupled to the second data node;a second cell transistor coupled to the second supply terminal and to the second data node and having a control terminal coupled to the first data node;a first access transistor having a gate and having first and second source/drain regions of a second conductivity that are disposed in the first semiconductor region, the gate coupled to the enable terminal, the first source/drain region coupled to the first access terminal, and the second source/drain region coupled to the first data node;a second access transistor having a gate and having first and second source/drain regions of the second conductivity that are disposed in the second semiconductor region, the gate coupled to the enable terminal, the first source/drain region coupled to the second access terminal, and the second source/drain region coupled to the second data node;a third semiconductor region disposed in the first semiconductor region, contiguous with the second source/drain region of the first access transistor, and having a third doping concentration of the first conductivity, the third concentration being significantly greater than the first concentration; anda fourth semiconductor region disposed in the second semiconductor region, contiguous with the second source/drain region of the second access transistor, and having a fourth doping concentration of the first conductivity, the fourth concentration being significantly greater than the second concentration.