JPS5923503A - 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 by a wet method, taking advantage of the film's selective etching properties.

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

Purpose of the Invention The present invention is intended to solve the above-mentioned drawbacks, and an object of the present invention is 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 the need for trimming. There is.

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

Manufacturing process diagrams according to the present invention are shown in FIGS. 1(a) to (h).

When manufacturing high-precision thin-film resistors, first of all, please refer to Figure 1 ((Z
), alumina ceramic, glass.

A resistive film 2 made of Ta2N, NiCr, etc. is formed on a substrate 1 made of sapphire or the like by sputtering or vapor deposition.

Next, as shown in FIG. 1(b), a resist pattern 6 is formed on the resistive film 2.

Next, using the resist pattern 3 as a mask, the portions of the resistive film other than the portion where the resist pattern 6 is formed are etched by dry etching such as ion milling as shown in FIG. 1(C). FIG. 2 is a plan view of the etching completed state.

Next, the resist pattern 3 is removed and the surface shown in FIG.
), a resist film 4 is formed as shown in FIG.
A hole 5 is left where the electrode will be formed later. FIG. 5 is a plan view in this state. The holes 5.5 are formed to surround both ends of the remaining resistive film (to become a resistor) 2, and the spacing rr' between the patterned holes 5, 5 guarantees the spacing between the electrodes to be formed later with high accuracy. .

Next, as shown in Figure 1 (g) from above, Aa, AI
A conductive film 6 such as the above is formed by sputtering or vapor deposition. When forming this conductive film, NiCr,
Films of Ti and Pd'J are formed in advance.

Next, a regimen pattern 7.7 for peeling around the electrode is formed thereon as shown in FIG. 1(j). This resist pattern 7.7 is formed in a portion corresponding to the holes 5, 5,
Its thickness is set to be slightly larger than the holes 5, 5 to the extent that mask displacement and side etching during subsequent etching can be sufficiently absorbed.

Next, wet etching is performed from above to form a resist pattern 7.7 of the conductor film B as shown in FIG. 1 (9).
Remove parts other than the forming part.

Finally, the resist film 4 and the resist pattern 7.7 are removed as shown in FIG. 1(A), thereby completing the formation of the thin film resistor. In this case, since the remaining conductor film is sandwiched between the resists, it is easily subjected to stress due to the swelling of the resist when the resist is peeled off, and the peelability is improved. As a result, Aa, AI, which are prone to peeling leakage, etc.
The peripheral portion of the conductor film made of materials such as the above and outside the hole 5 can be reliably removed, making it possible to form electrodes with high precision. FIG. 4 is a perspective view of the completed state shown in FIG. 1(A), in which a resistor 11. A thin film resistor 16 consisting of electrodes 12 and 12 is formed with high precision τ of dimensional accuracy of ±0.1 μm.

Effects of the Invention As described above, according to the present invention, the resistive film is etched by dry etching such as ion milling, and the conductive film is selectively formed using the lift-off method. Make sure that the peripheral part of the remaining conductor film (the part outside the hole), which is slightly larger than the hole corresponding to the hole, is removed when the two resists sandwiching this conductor film are removed. This allows highly accurate thin film resistors to be obtained without the need for trimming. Further, the present invention can also be applied to ultra-miniaturization.

[Brief explanation of drawings]

The drawings show an embodiment of the method for manufacturing a high-precision thin film resistor according to the present invention, and FIG. FIG. 6 is a plan view showing the process completion state of FIG. 1(d), and FIG. 4 is a perspective view showing the process completion state of FIG. 1(h). In the figure, 1 is a substrate, 2 is a resistive film, 6 and 7 are resist patterns, 4 is a resist film, 5 is a hole, 6d is a conductor film, 11 is a resistor, 12 is an electrode, and 16 is a thin film resistor. Patent applicant Fujitsu Limited

Claims (1)

[Claims] A resistive film is formed on a substrate, a resist pattern is formed on the resist pattern, and dry etching is performed from above to remove the resistive film in areas other than the resist pattern forming area.
After removing the resist pattern and forming a resist film having holes surrounding both ends of the remaining resistive film, a conductive film is formed on the surface of the resist film, and then a conductive film is formed on the conductive film. After forming a resist pattern for peeling around the electrode in a slightly wider area than the stone part corresponding to the hole, the resist pattern for peeling around the electrode is wet-etched from above. A method for manufacturing a high-precision thin film resistor, comprising removing the conductive film in a portion other than the pattern forming portion, and finally removing the resist film and the resist pattern for stripping around the electrode.