Thin film resistor crossovers for integrated circuits

• US 3,876,912 A
• Filed: 08/27/1973
• Issued: 04/08/1975
• Est. Priority Date: 07/21/1972
• Status: Expired due to Term

• Current Assignee: Thomas J. Sanders
• Original Assignee: Thomas J. Sanders
• Inventors: Sanders, Thomas J.
• Primary Examiner(s): Goldberg, E. A.
• Application Number:
  US05/391,572
• Time in Patent Office: 589 Days
• Field of Search: 317/11A,11CE 338/308,309,254,334 117/217
• US Class Current: 361/765
• CPC Class Codes: H01C 13/02 Structural combinations of resistors impedance networks per se H03H
• CPC Class Codes: H01L 21/00 Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
• CPC Class Codes: H01L 23/522 including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/3011 Impedance

Abstract

Thin film resistors with metal connector crossovers are fabricated on smooth nonconducting materials. The thin film resistor crossover regions are delineated by a photo-resist emulsion. After deposition of an insulator, the photo-resist material is chemically removed, leaving insulating material only in the crossover regions. Metal connectors and interconnectors are applied and delineated to the resistor and over the insulator respectively.

Claims

1. An integrated circuit including a thin film resistor comprising:

a silicon substrate;

a first dielectric layer overlying said substrate and adherent thereto;

said thin film resistor in the form of a strip of electrical resistance material having substantially uniform thickness in the range of 200-300 angstroms and substantially uniform width throughout its length, overlying said first dielectric layer and adherent thereto;

a second dielectric layer of substantially uniform thickness in the range of 1,000-3,000 angstroms overlying said thin film resistor intermediate the length thereof and adherent thereto, and having a substantially uniform width slightly greater than that of said thin film resistor to overlie said first dielectric layer in adherent relationship therewith at both sides of said thin film resistor, and said second dielectric layer having a length shorter than that of said thin film resistor to expose the end portions thereof; and

a plurality of substantially parallel spaced apart electrically conductive strips extending transversely across said thin film resistor, two of said conductive strips overlying and in adherent electrical contact with the respective ends of said thin film resistor, and a further one of said plurality of conductive strips overlying said second dielectric layer and adherent thereto to form a conductive crossover for interconnecting desired points of said integrated circuit while electrically insulated from said thin film resistor, each of said conductive strips extending beyond the sides of said thin film resistor in direct adherent overlying relationship with said first dielectric layer thereat.

2. An integrated circuit as in claim 1 wherein said second dielectric layer is pinhole free.

3. An integrated circuit as in claim 1 wherein said thin film resistor is CrSi.sub.2, MoSi.sub.2, or NiCr.

4. An integrated circuit as in claim 1 wherein said first dielectric layer is SiO and said second dielectric layer is SiO.sub.2.