JPH0322491A - Manufacture of thin-film integrated circuit - Google Patents

Abstract

PURPOSE:To prevent a flaw, a stain, a smear, oxidation and others of a conductor layer and thereby to improve reliability by a method wherein a thin-film resistance layer and the conductor layer are stacked on an insulative substrate, an insulative thin film is so formed on the conductor layer as to be used as a protection film for the conductor layer in processes of patterning and heat treatment, and this insulative thin film is removed after the heat treatment. CONSTITUTION:A thin-film resistance layer 2 is formed on an insulative substrate 1. A thin-film conductor layer 3 is deposited thereon and an silicon oxide film 4 is deposited further this layer. A photoresist film 5 is applied thereon by coating and exposure-development and patterning are applied. With this film used as a mask, subsequently, the silicon oxide film 4 and the thin film conductor layer 3 are etched to be removed sequentially and the thin-film conductor layer 3 is patterned. After the photoresist film 5 is removed, a photoresist film 6 is applied on the whole surface by coating and patterned, and with this film used as a mask, the thin-film resistance layer 2 is etched, so as to form a resistance layer pattern. After the photoresist film 6 is removed, subsequently, heat treatment is executed to remove the silicon oxide film 5, and thus a thin- film integrated circuit is constructed.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for manufacturing thin film integrated circuits.

[Conventional technology]

As shown in FIG. 2(a), the conventional method for manufacturing thin film integrated circuits involves forming a thin film resistance layer 2 made of a tantalum nitride thin film having a resistance temperature coefficient of -90xlO-'/t on an insulating substrate 1. A thin film conductor layer 3 of NiCr/Au, Ti/Pa/Au, Aj, etc. is deposited on the thin film resistance layer 2 by magnetron sputtering, and a photoresist film 5 is applied on the thin film conductor layer 3. Using the pattern 2 as a mask, the thin film conductor layer 3 is etched to form a conductor layer pattern.

Next, as shown in FIG. 2(c), after removing the photoresist film 5, a photoresist film 6 is applied and patterned, and the thin film resistance layer 2 is etched using the photoresist film 6 as a mask to form a conductive layer. .

Next, as shown in FIG. 2(d), after removing the photoresist film 6, heat treatment is performed in air at 250 to 450°C to obtain stability over time of the thin film resistive layer 2, and a thin film integrated circuit is constructed. There is.

[Problem to be solved by the invention]

In the conventional thin film integrated circuit manufacturing method described above, the photoresist film coated on the thin film conductor layer is not coated on the conductor layer due to the residue generated in the process of peeling off the photoresist film after butter-buttering the thin film conductor layer. When forming the b1 pattern, there was a problem in that it caused scratches and reduced reliability.

When an M-based thin film conductor layer is used in the case, if heat treatment is performed after pattern formation to obtain stability over time of the thin film resistance layer, the surface of the M film is likely to oxidize, which may cause contact resistance. There is a drawback that the measurement accuracy of the b1 thin film resistance layer is adversely affected.

[Means to solve the problem]

The method for manufacturing a thin film integrated circuit of the present invention includes the steps of: sequentially laminating and providing a thin film resistance layer and a thin film conductor layer on an insulating substrate; forming an oxidation-resistant insulating film on the thin film conductor layer;
A step of selectively etching the insulating film and the thin film conductor layer to form a conductor layer; a step of selectively etching the thin film resistive layer to form a resistive layer pattern; and stabilizing the resistive layer. The method includes a step of removing the insulating film after performing a heat treatment for oxidation.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIGS. 1(a) to 1(e) are cross-sectional views shown in the order of steps for explaining one embodiment of the present invention.

First, as shown in FIG. 1(a), a thin film resistance layer 2 is formed on an insulating substrate 1 made of glass, ceramic, etc.
A thin film conductor layer 3 of tantalum nitride is formed on the thin film resistance layer 2 with a temperature coefficient of resistance of
/Pd/Au or M thin film is deposited to a thickness of 0.4 μm by magnetron sputtering, and a silicon oxide film 4 of about 1 μm thick is deposited on the thin film conductor layer 3 by high frequency sputtering.
Deposit. Next, a photoresist film 5 is coated on the silicon oxide film 4 and patterned by exposure and development.

Next, as shown in FIG. 1(b), the silicon oxide film 4 and the thin film conductor layer 3 are sequentially etched and removed using the photoresist film 5 as a mask, and the thin film conductor layer 3 is patterned.

Next, as shown in FIG. 1(C), after removing the photoresist film 5, a photoresist film 6 is applied and patterned on the entire surface, and the thin film resistive layer 2 is formed using the photoresist film 6 as a mask.
It is provided by etching and laminating the resistor.

Next, as shown in FIG. 1(d), after removing the J photoresist film 6, heat treatment is performed in air at 250 DEG C. to 450 DEG C. in order to obtain stability over time of the thin film resistance layer.

Next, as shown in FIG. 1(e), the silicon oxide film 4 is removed to form a thin film integrated circuit.

This prevents stains and smearing on the conductor film due to insufficient peeling of the resist, and prevents surface oxidation of the M film when the M film is used as a thin film conductor layer.

Note that a silicon nitride film may be used in place of the silicon oxide film b.

〔Effect of the invention〕

As explained above, in the present invention, a thin film resistance layer and a conductor layer are sequentially laminated on an insulating substrate, and the insulating thin film is formed on the conductor layer, and the conductor is subjected to a patterning and heat treatment process. By removing this insulating thin film after heat treatment, it is possible to prevent stains and stains on the surface of the conductor layer due to scratches on the conductor layer during pattern formation and residual photoresist film, etc. It also has the effect of preventing oxidation of the conductor layer surface due to heat treatment and improving reliability.

[Brief explanation of drawings]

FIGS. 1(a) to (e) are cross-sectional views shown in the order of steps for explaining one embodiment of the present invention, and FIGS. 2(a) to (d) are
1A and 1B are cross-sectional views illustrating a conventional method for manufacturing a thin film integrated circuit in order of steps. 1...Insulating substrate, 2...Thin film resistance layer,
3... Thin film conductor layer, 4... Silicon oxide film, 5, 6... Photoresist film.

Claims (1)

[Claims] A step of sequentially laminating and providing a thin film resistance layer and a thin film conductor layer on an insulating substrate, a step of forming an oxidation-resistant insulating film on the thin film conductor layer, and a step of selectively stacking the insulating film and the thin film conductor layer. a step of sequentially etching to form a conductive layer pattern; a step of selectively etching the thin film anti-resistance layer to form a resistive layer pattern; A method for manufacturing a thin film integrated circuit, comprising the step of removing a film.