Electrically alterable resistive component stacked above a semiconductor substrate

• US 5,296,722 A
• Filed: 01/26/1993
• Issued: 03/22/1994
• Est. Priority Date: 02/23/1981
• Status: Expired due to Term

• Current Assignee: Unisys Corporation
• Original Assignee: Unisys Corporation
• Inventors: Genter, Melvyn E., Roesner, Bruce B., Potash, Hanan
• Primary Examiner(s): LARKINS, WILLIAM
• Application Number:
  US08/009,372
• Time in Patent Office: 420 Days
• Field of Search: 357/59, 357/2, 257/50, 257/51
• US Class Current: 257/50
• CPC Class Codes: H10B 20/00 Read-only memory [ROM] devices
• CPC Class Codes: Y10S 257/91 Diode arrays, e.g. diode read-only memory array

Abstract

A memory cell includes a pair of spaced apart conductors on an insulating layer, and a novel electrically alterable resistive component between the conductors. This resistive component consists essentially of a single element semiconductor selected from the group of Si, Ge, C, and α-Sn, having a crystalline grain size which is smaller than polycrystalline. Dopant atoms in the semiconductor are limited to be less than 10¹⁷ atoms/CM³ ; and, such a doping range includes zero doping. All dopant atoms are interstitial in the semiconductor crystals and not substitutional.

Claims

1. An electrically alterable resistive component in an integrated circuit;

said circuit including a substrate having a major surface, a patterned insulating layer on said surface, and a polycrystalline silicon member which has large crystalline grains that occur in silicon when it is subjected to temperatures above 600°

C.; and

said electrically alterable resistive component being comprised of;

a pair of spaced apart conductors, supported by said insulating layer, for applying a threshold voltage thereacross;

a switching material serially coupled between said conductors for receiving said threshold voltage;

said switching material consisting essentially of silicon having less than 10¹⁷ dopant atoms per CM³ and having small crystalline grains that occur in silicon which is deposited at temperatures below 600°

C. and confined to such temperatures;

whereby said switching material will exhibit a high resistance that will irreversibly switch to a low resistance without the flowing of any metal therethrough upon the application of said threshold voltage thereacross.

2. The invention of claim 1, wherein said dopant atoms in said switching material consist of intrinsic impurities.

3. An electrically alterable resistive component in an integrated circuit;

said circuit including a substrate having a major surface, and a patterned insulating layer on said surface and said electrically alterable resistive component being comprised of;

a pair of spaced apart conductors, supported by said insulating layer, for applying a threshold voltage thereacross;

a switching material serially coupled between said conductors for receiving said threshold voltage;

said switching material consisting essentially of silicon having less than 10¹⁷ dopant atoms per CM³ and having small crystalline grains, relative to the spacing of said conductors, such that many grains are crossed in traversing said switching material from one conductor to the other;

whereby said switching material will exhibit a high resistance that will irreversibly switch to a low resistance without the flowing of any metal therethrough upon the application of said threshold voltage thereacross.

4. The invention of claim 3, wherein said dopant atoms in said switching material consist of intrinsic impurities.