Patent ID: 6716764
Filing Date: 2004-04-06
Classification: H01L

Abstract:
A method of forming contacts and metal lands onto a semiconductor structure at the first level of metallization comprising the steps of:(a) providing a silicon substrate with diffusion regions formed therein and a plurality of gate conductor stacks comprising a composite doped polysilicon/refractory metal/silicon nitride layer thereon, said structure being passivated by at least one insulating layer; (b) forming at least one contact hole of a first type through said at least one insulating layer to expose at least a portion of at least one diffusion region of said substrate; (c) filling said contact hole of the first type and exposing a diffusion region with doped polysilicon to form at least one conductive stud therein, said stud being substantially coplanar with the exposed surface of said insulating layer; (d) forming a first mask on an exposed surface of said structure to expose at least one land recess location and at least one of said conductive studs; (e) anisotropically dry etching said masked structure to create land recesses in said insulating layer; (f) removing said mask; (g) forming a second mask at the surface to said structure to expose desired contact hole locations of a second type in at least one of said land recesses to form at least one contact hole of a second type and at least one contact hole of a third type, wherein said contact hole of the second type is located above at least one gate conductor stack and said contact hole of the third type is located above at least one diffusion region; (h) anisotropically dry etching the resulting masked structure to create at least one contact hole of the second type and at least one contact hole of the third type, such that at least a portion of at least one diffusion region and at least a portion of at least one refractory metal layer of at least one gate conductor stack is exposed; (i) removing said second mask; and (j) filling said land recesses and said contact hole of the second type and said contact hole of the third type with at least one electrically conductive material such that the top surface of said electrically conductive material and said insulating material top surface are substantially coplanar.