Fine-line thick film resistors and resistor networks and method of making same

• US 5,548,268 A
• Filed: 06/02/1995
• Issued: 08/20/1996
• Est. Priority Date: 10/06/1993
• Status: Expired due to Fees

• Current Assignee: Franklyn M. Collins
• Original Assignee: Franklyn M. Collins
• Inventors: Collins, Franklyn M.
• Primary Examiner(s): HOANG, TU BA
• Application Number:
  US08/460,062
• Time in Patent Office: 445 Days
• Field of Search: 338/34, 338/307, 338/308, 338/320, 427/96, 427/372.2, 347/148, 347/150, 29/854, 216/87, 216/95, 216/100
• US Class Current: 338/307
• CPC Class Codes: H01C 13/02 Structural combinations of resistors impedance networks per se H03H
• CPC Class Codes: H01C 3/12 lying in one plane
• CPC Class Codes: H01C 3/20 wound on cylindrical or prismatic base H01C3/16 takes precedence
• CPC Class Codes: Y10T 29/49099 Coating resistive material on a base

Abstract

Electrical resistors and resistor networks are provided on an insulative substrate with designated conductive terminations by direct and continuous writing of resistive lines in fine-line patterns between and over each two of neighboring terminations from heterogeneous resistive thick film compositions. The resistive lines of line width w and total length l between conductive terminations can be directly written by suitable writing apparatus to have a high aspect ratio n=l/w, thereby providing resistors and resistor networks of high resistance values on an overall substrate area significantly smaller than required for conventional thick film resistors of comparable resistance value and comparable operational characteristics.

Claims

1. A method for providing a resistor and a resistor network, comprising the steps of:

furnishing an insulative substrate;

forming designated conductive terminations on the substrate;

selecting a directly writeable heterogeneous resistive composition having a sheet resistivity ρ

_sheet ;

choosing a line pattern, a line width w and a total line length l of a resistive line to be deposited on said substrate between at least two of said terminations; and

writing directly and continuously between and onto at least two of said terminations an electrically resistive line of said chosen pattern, line width and total line length from said selected composition so as to achieve a desired value of resistance R of a resistor and a resistor of a resistor network in accordance with the relationship R=ρ

_sheet ×

l/w.

2. The method according to claim 1, wherein said selecting and said choosing steps further comprise the steps of:

electing said line pattern such that said directly written resistive line has an aspect ratio n=l/w; and

supplying a resistive line writing apparatus with the directly writeable composition having a sheet resistivity value ρ

_sheet such that the desired value of resistance R is achieved.

3. The method according to claim 1, wherein said line pattern choosing step includes the step of choosing a serpentine pattern of the resistive line.

4. A method for providing a multiplicity of identical resistors, comprising the steps of:

furnishing an insulative substrate;

forming a multiplicity of designated conductive terminations on the substrate;

selecting a directly writeable heterogeneous resistive composition having a sheet resistivity ρ

_sheet ;

choosing a line pattern, a line width w and a total line length l of a resistive line to be deposited on said substrate between each of two neighboring ones of said terminations; and

writing directly and continuously between and over each of said two neighboring ones of said terminations an electrically resistive line of said chosen pattern, width and total length from said selected composition so as to achieve a multitude of resistors each of which having a desired value of resistance R in accordance with the relationship R=ρ

_sheet ×

l/w.