Patent ID: 6022794
Filing Date: 2000-02-08
Classification: H01L

Abstract:
A method of manufacturing the buried contact window of a static random access memory (SRAM) cell, the method comprising the steps of:providing a first conductive conductive-type substrate having a device isolation structure thereon;forming an oxide layer, a first conductive layer and a sacrificial layer over the substrate;patterning the oxide layer, the first conductive layer and the sacrificial layer to expose a first region in the substrate for forming the desired buried contact window;performing a first ion implantation forming a first heavily doped region of a second conductive type in the substrate underneath the first region;forming a metallic layer over the substrate that covers at least the first region;performing a heat treatment so that the metallic layer above the first region reacts to form a metal silicide layer;removing the unreacted metallic layer and the sacrificial layer;forming a second conductive layer and a third conductive layer over the substrate; andpatterning the second conductive layer and the third conductive layer to form a conductive line layer and a gate stack exposing a second region between the conductive line layer and the gate stack for forming a source/drain region, wherein the conductive line layer and the metal silicide layer are electrically coupled.