JPS5923504A - Method of producing high accuracy thin film resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION The present invention relates to a method of manufacturing high precision thin film resistors.

Prior Art and Problems Conventionally, when forming a thin film resistor on the surface of a substrate, the resistive film and the conductive film are etched using a wet method utilizing the selective etching properties of the film.

Although such conventional methods are suitable for mass production, dimensional accuracy decreases due to side etching, etc., and a trimming process is essential when making high-precision resistors. Furthermore, there is a limit to the ability to respond to miniaturization in terms of dimensional accuracy.

Purpose of the Invention The present invention is intended to solve the above-mentioned drawbacks, and it is an object of the present invention to provide a method for manufacturing a high-precision thin-film resistor, which can obtain a high-precision thin-film resistor including an ultra-small one without requiring trimming. It is said that

Examples of the invention The invention will now be described in detail in conjunction with the drawings.

When manufacturing a high-precision thin film resistor, first, as shown in FIG. 1(a), a conductive film 2 of Au, AI, etc. is formed on a substrate 1 of ceramics, glass, sapphire, etc. by sputtering, vapor deposition, etc. .

Next, on the portion of the conductive film 2 to be left as an electrode,
) As shown in FIG. 1(C), a resist layer 3 is selectively formed, and dry etching such as ion milling is performed on the resist layer 3 to remove the conductive film other than the area where the resist layer 3 is formed, as shown in FIG. 1(C). Electrode 4 is formed. After forming the electrode 4, the resist layer 3 is removed.

Next, on the substrate 1 including the electrodes 4 thus formed, a resistive film 5 is uniformly formed by sputtering, vapor deposition, etc., as shown in FIG. 1(, 7).

Next, as shown in FIG. 1(g), a resist pattern 6 is selectively formed on the electrode 4 and the resistive film 5 to be left as a resistor.

Next, dry etching such as ion milling is performed from above to remove the resistive film outside the area where the resist pattern 6 is formed and form the resistor 7, as shown in FIG. Afterwards, the resist pattern 6 is removed.

Next, as shown in FIG. 1(V), a resist film 8 is formed on the substrate 1 including the resistor 7. In this case, electrodes 4, 4
Holes 9, 9 are left at positions facing the center of.

Next, by wet etching, the first [>l (A
), the resistors in the holes 9, 9 are selectively removed.

Although omitted in the above process description, the electrode 4 and the resistor 7
NiCr to improve film adhesion between 0 and 0.

If an intermediate film of Ti, Pd, etc. is formed, this intermediate film is also selectively removed by wet etching if necessary. In this state, windows 10, 10 corresponding to the holes 9.9 are formed in the resistor 7, and the centers of the boxes and poles 4, 4 are exposed within the windows 10.10.

Finally, the resist film 8 is removed to complete the formation of the thin film resistor. FIG. 2 is a diagram showing this state.

The thin film resistor is formed by the process described above, and the positive electrode and the resistor are formed by dry etching the conductor film and the resistor film, so the width of the resistor is small.

It is possible to manufacture the length etc. with high accuracy, and it is possible to obtain a highly accurate thin film resistor. In addition, since there is no need to etch the electrode surface, there is no need to form a particularly thick conductor film for the electrode, and it is also possible to etch areas where dimensional accuracy is not critical (the process of forming a window for exposing the center of the electrode on the resistor). ) is done using a wet method, so
It is possible to reduce costs.

Effects of the Invention As described above, according to the present invention, it is possible to manufacture a high precision thin film resistor at low cost.

[Brief explanation of the drawing]

The drawings show an embodiment of the method for manufacturing a high-precision thin film resistor according to the present invention, and FIGS. 1(a) to (A) are manufacturing process diagrams of the thin film resistor, and FIG. 2 is a diagram showing a thin film formed on a substrate. FIG. 3 is a perspective view of a resistor. In the figure, 1 is a substrate, 2 is a conductor film, 6 is a resist layer, and 4 is a t
b1 pole, 5 is a resistive film, 6 is a resist pattern, 7 is a resistor, 8 is a resist film, 9 is a hole, and 1o is a window. 1st line applicant Fujitsu Limited

Claims (1)

[Claims] After forming a conductive film on a substrate and forming a resist layer on the portion of the conductive film to be left as an electrode, dry etching is performed from above to remove the conductive film other than the resist layer forming portion. After forming a resistive film uniformly on the substrate including the electrode by removing the resist layer, a resist pattern is formed on the electrode and the resistive film that is to be left as a resistor. Next, dry etching is performed from above to remove the resistive film other than the resist pattern forming area to form a resistor, and then, after removing the resist pattern, the resistive film is etched onto the substrate including the resistor. A resist film is formed leaving a hole at a position facing the center of the electrode, and then the large facing portion of the resistor is removed by wet etching, and finally the resist film is removed. A method for manufacturing a high-precision thin film resistor, characterized by: