公开(公告)号：US09761302B1

公开(公告)日：2017-09-12

申请号：US15092613

申请日：2016-04-06

Applicant: UNITED MICROELECTRONICS CORP.

Inventor： Tien-Yu Lu ,  Chang-Hung Chen ,  Chun-Hsien Huang ,  Han-Tsun Wang ,  Jheng-Tai Yan ,  Yu-Tse Kuo

IPC: G11C11/34 ,  G11C11/417 ,  G11C11/412 ,  H01L27/105

CPC classification number: G11C11/417 ,  G11C8/16 ,  G11C11/412 ,  G11C11/418 ,  G11C11/419 ,  H01L27/0207 ,  H01L27/105 ,  H01L27/1104

Abstract: A SRAM cell includes a first pass-gate device and a second-pass gate device comprising a first conductivity type, a first pull-down device and a second pull-down device comprising the first conductivity type, and a first pull-up device and a second pull-up device comprising a second conductivity type complementary to the first conductivity type. The first pass-gate device and the second pass-gate device respectively include first lightly-doped drains (hereinafter abbreviated as LDDs. The first pull-down device and the second pull-down device respectively include second LDDs. And a dosage of the first LDDs is different from a dosage of the second LDDs.