Patent · US Expired

Semiconductor memory and manufacturing method thereof

US6303422A · kind A · utility

6Cited by
5References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 9, 1999
Grant dateOct 16, 2001
Priority date
Expiry dateJun 9, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/0002
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A semiconductor memory in which a layout margin at the contact hole between wiring layers of a SRAM does not need and the wiring capacity at bit lines is reduced and the high speed processing is made to be possible is provided. The SRAM is constituted of a pair of driving transistors Qd1 and Qd2, a pair of transferring transistors Qt1 and Qt2, high resistance loads R1 and R2, a pair of bit lines BL1 and BL2, and a VCC line and a GND line. Gate electrodes of each transistor and word lines are formed at a first layer, the high resistance loads are formed at a second layer, the VCC line and the GND line are formed at a third layer, and the bit lines are formed at a fourth layer. A shared contact hole using for connecting the high resistance loads to the source/drain area of transistors does not penetrate the other conductive layers. Therefore, the layout margin between the shared contact hole and the other conductive layers becomes unnecessary and the reduction of the cell size becomes possible.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.