Capacitance type sensitive element and a manufacturing method thereof

• US 4,893,214 A
• Filed: 09/09/1988
• Issued: 01/09/1990
• Est. Priority Date: 09/29/1987
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Murakami, Kouji, Nishiwaki, Satoru, Takahashi, Yukinobu, Fukuda, Norisuke
• Primary Examiner(s): GRIFFIN, DONALD
• Application Number:
  US07/242,201
• Time in Patent Office: 487 Days
• Field of Search: 73/336.5, 29/25.42, 361/286
• US Class Current: 361/286
• CPC Class Codes: G01N 27/225 by using hygroscopic materials
• CPC Class Codes: Y10T 29/435 Solid dielectric type

Abstract

A capacitance type sensitive element comprises a pair of electrode pairs formed on an insulating substrate and having opposite electrode faces perpendicular or slantingly formed with respect to a face of the insulating substrate; and a sensing material disposed between the opposite electrode faces of the electrodes and having electrical characteristics changed on the basis of the physical or chemical interaction between the sensing material and a substance to be detected.

A method for manufacturing a capacitance type sensitive element comprises the steps of forming a groove on an insulating substrate; forming a metallic thin film having a predetermined thickness on the insulating substrate having the groove; performing the etching of a predetermined pattern in a portion including a bottom face portion of the groove in the metallic thin film, and forming a pair of electrodes; coating the entire surface of the pair of electrodes and the insulating substrate with a humidity sensitive material, and thereafter hardening the coated humidity sensitive material; and patterning the hardened humidity sensitive material.

A method for manufacturing a capacitance type sensitive element may comprise the steps of forming a metallic thin film having a predetermined thickness on an insulating substrate; patterning the metallic thin film and forming a pair of electrodes at a predetermined distance; coating the entire surface of the insulating substrate including a pair of electrodes with a humidity sensitive material, and thereafter hardening the coated humidity sensitive material; and patterning the hardened humidity sensitive material.

Claims

1. A capacitance type sensitive element comprising:

a pair of electrodes formed on an insulating substrate and having opposite electrode faces perpendicular or slantingly formed with respect to a face of the insulating substrate; and

sensitive material disposed between the opposite electrode faces of the pair of electrodes and on both of the electrodes and having electrical characteristics changed on the basis of the physical or chemical interaction between the sensing means and a substance to be detected.

2. A capacitance type sensitive element as claimed in claim 1, wherein two electrodes having a predetermined thickness are disposed on the insulating substrate in parallel to each other, and the opposite electrode faces are formed on opposite side wall faces of the two electrodes.

3. A capacitance type sensitive element comprising:

electrode pair means formed on an insulating substrate and having opposite electrode faces perpendicular or slantingly formed with respect to a face of the insulating substrate; and

sensing means disposed between the opposite electrode faces of the electrode pair means and having electrical characteristics changed on the basis of the physical or chemical interaction between the sensing means and a substance to be detected, wherein the electrode pair means is disposed on opposite inner wall faces of a groove disposed in the insulating substrate.

4. A method for manufacturing a capacitance type sensitive element comprising the steps of:

forming a groove on an insulating substrate;

forming a metallic thin film having a predetermined thickness on the insulating substrate having the groove;

performing the etching of a predetermined pattern in a portion including a bottom face portion of the groove in the metallic thin film, and forming a pair of electrodes;

coating the entire surface of the pair of electrodes and the insulating substrate with a humidity sensitive material, and thereafter hardening the coated humidity sensitive material; and

patterning the hardened humidity sensitive material.

5. A manufacturing method as claimed in claim 4, wherein the humidity sensitive material is composed of a high polymer material.

6. A manufacturing method as claimed in claim 4, wherein the groove is approximately in the shape of a V.

7. A method for manufacturing a capacitance type sensitive element comprising the steps of:

forming a metallic thin film having a predetermined thickness on an insulating substrate;

patterning the metallic thin film and forming a pair of electrodes at a predetermined distance;

coating the entire surface of the insulating substrate including a portion between the pair of electrodes and a portion on the both of the electrodes with a humidity sensitive material, and thereafter hardening the coated humidity sensitive material; and

patterning the hardened humidity sensitive material.

8. A manufacturing method as claimed in claim 7, wherein the humidity sensitive material is composed of a high polymer material.

9. A manufacturing method as claimed in claim 7, wherein the pair of electrodes are spaced apart from each other by vertical opposite wall portions thereof.