JPH09190905A - Thick film thermistor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture an element of accurate resistance value by cutting a comb-type pattern of an electrode for adjusting a resistance value so that a temperature change of a thermistor film is made small, in a thick film thermistor wherein a thick film paste is printed on a plurality of comb-type electrodes formed on an insulating substrate. SOLUTION: A platinum film 2 is formed on an insulating substrate 1 in a sputtering manner, and it is thermal-treated for stabilization, and an electrode layer is obtained. On the film-coated base material, a pattern whose width of a comb part is 50μm is manufactured by photo resist, and the base material is etched by trimming, and then, photo-resist is removed, and, with the use of a printing method, a termistor paste is printed and burned on a specified part on the electrode 2, for obtaining a thermistor film 5. The first adjustment part 6 of the film-coated base material is cut by laser trimming, and resistant value is adjusted to 95-100% of a desired resistance, and further the second adjustment part 7 is cut for obtaining the desired resistant value. Glass is printed and burned on an element whose resistant adjustment had performed, for obtaining a thermistor element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermistor using a thick film for a temperature sensitive part.

[0002]

2. Description of the Related Art A conventional thermistor using a thick film is formed by forming a thick film thermistor layer on an electrode pattern formed by thick film printing, and then cutting the thermistor film with a laser beam to adjust the resistance value. Was there.

[0003]

When the thermistor film is cut by laser light, high heat is applied to the thermistor film by the laser light, and the resistance value fluctuates due to the characteristics of the thermistor, making it difficult to manufacture a device having a precise resistance value. It was

[0004]

According to the present invention, since the electrode structure is made into a plurality of comb shapes and the electrode portions are cut by laser light, the temperature change of the thermistor film is reduced and the resistance value is adjusted. It is possible to manufacture an element having a resistance value.

[0005]

[Operation] Since the thermistor according to the present invention cuts the electrode portion in the resistance value adjusting step, the resistance value change due to heat of the thermistor film is small and the resistance value can be precisely adjusted.

[0006]

Embodiment 1 An embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, 2 mm × 1.25 mm ×
After depositing platinum to a thickness of 0.5 μm on a 0.4 mmt alumina insulating substrate by a sputtering method, a heat treatment was performed at 800 ° C. to stabilize the platinum film to obtain an electrode layer.

A pattern having a comb portion width of 50 μm as shown in FIG. 2 was formed on the film-forming substrate by photoresist.

After etching this substrate by milling, the photoresist was removed to form the electrode shown in FIG.

A thermistor paste is printed on the electrode on the portion shown in FIG.
A thermistor film of μm was obtained.

As shown in FIG. 5, the first adjusting portion of this film-forming substrate is cut by laser trimming, the resistance value is adjusted to 95% to 100% of the desired resistance, and the second adjusting portion is cut. To obtain a desired resistance value.

The element whose resistance value was adjusted was printed with glass and baked as shown in FIG. 6 to manufacture a thermistor element.

[0013]

EFFECT OF THE INVENTION 10 kΩB produced by the method according to the present invention
Table 1 shows the variation in resistance between 100 thermistor elements with characteristics of 4000K and 100 thermistors manufactured by the conventional method.
Shown in

[Brief description of the drawings]

FIG. 1 is a sectional view of an element according to a first exemplary embodiment.

FIG. 2 is a top view of the element in Example 1.

FIG. 3 is a top view of the element in Example 1.

FIG. 4 is a top view of the element in Example 1.

FIG. 5 is a top view of the element in Example 1.

FIG. 6 is a top view of the element in Example 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Alumina insulating substrate 2 Platinum film 3 Comb part 4 Photoresist 5 Thermistor film 6 1st adjusting part 7 2nd adjusting part 8 Glass

Claims (3)

[Claims] 1. A thick film thermistor in which a thick film paste is printed on a plurality of comb-shaped electrodes formed on an insulating substrate,
A thick film thermistor characterized by cutting a comb pattern of electrodes to adjust a resistance value. 2. The electrode film according to claim 1, wherein the electrode film is platinum or
Thick film thermistor using platinum alloy. 3. A thick film thermistor according to claim 2, wherein the electrode film is a thin film.