Patent · US Expired

Method of making self-aligned, planarized contacts for semiconductor devices

US4977108A · kind A · utility

23Cited by
5References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 13, 1989
Grant dateDec 11, 1990
Priority date
Expiry dateApr 13, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S148/141
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A novel process is provided for fabricating contacts (46s, 40g, 46d) in a novel, completely self-aligned, planarized configuration for transistors (14), with self-aligned interconnections (46c). The process of the invention permits higher packing densities, and allows feature distances to approach 0.5 .mu.m and lower. A unique combination of masks in conjunction with a multi-layer structure (28) formed on the surface of a semiconductor wafer (16), the multi-layer structure including a buried etch-stop layer therein (28b), defines the source (18), gate (22), and drain (20) elements and their geometry relative to each other and to interconnects. Polysilicon plug (40, 46) contacts through slots in the multi-structure layer permit vertical contact to be made to the various elements. Silicidation (56) of the polysilicon plugs reduces series resistance in the vertical direction and permits strapping of N.sup.+ and P.sup.+ polysilicon plugs.

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