JPS6031260A - Manufacture of hybrid integrated circuit - Google Patents

Abstract

PURPOSE:To prevent the discoloration of a substrate by complete removal of resist residue by a method wherein pure water jet washing and solvent vapor phase drying are carried out before high temperature heat treatment in the air after the photo resist on the substrate surface is exfoliated. CONSTITUTION:A Ta thin film 2 and a well-conductive metal 3 are adhered on the surface of the ceramic substrate 1, and then selectively removed by etching, resulting in the formation of a thin film circuit pattern. An NiCr-Pd-Au metallic film 6 is deposited on the back surface of this substrate 1, the photo resist 7 for pattern protection being provided on the substrate surface, and the photo resist 8 for pattern formation on the substrate back, respectively, and then the metallic film 6 is selectively etched. After exfoliation of the photo resists 7 and 8, foreign matters and resist residue are removed by a pure water jet washing 9 under a jet pressure of approx. 80-100kg/cm<2>, and the solvent drying and washing is performed, and the substrate is heat-treated in the ambient air.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a hybrid integrated circuit, and particularly to a method for manufacturing a high quality tantalum thin film circuit with an excellent 1g requirement.

Conventionally, a method for manufacturing a thin film circuit in which different gold films are formed on both sides of the same substrate is as follows. First, a tantalum-based thin film is deposited on an insulating substrate such as glass or ceramic by sputtering, and then NiCr-P is deposited on the film.
A highly conductive metal film such as d-Au or 'l'i-Pd-Au is formed by sputtering or vacuum evaporation. Next, the metal film is selectively etched step by step using a known photoresist process to form a desired thin film pattern. Next, NiCr-Au or Ni is deposited on the back side of the substrate.
A metal film of Cr-Pd-Au is deposited by sputtering, and the nuclear maple film is similarly treated with photoresist to form the desired Y! , forming an L% pattern.

However, when forming a thin film pattern on the back surface of the C.1% substrate using the above manufacturing method, in order to prevent the pattern formed on the surface from being damaged during the etching process, a photo film is naturally used to promote the pattern surface. Coat the resist. At this time, the photoresist covers not only the pattern portion but also the surface of the substrate. When the substrate material is ceramic or the like, the removability of the photoresist on the surface of the substrate during peeling is relatively unstable, unlike on a metal film, and there is a high risk that photoresist residue will remain. It is in.

If high-temperature heat treatment is performed in this state, a thermal reaction will occur between the photoresist residue and the substrate, and the surface of the substrate will turn light brown, detracting from the aesthetic appearance of the thin film circuit formed by photoetching.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a hybrid integrated circuit that eliminates the drawbacks of the above-mentioned manufacturing methods.

The method of the present invention involves forming a thin film circuit pattern on both sides of a substrate by a known photoetching process, peeling off the photoresist coated on the front surface and the photoresist on the pattern on the back surface, and performing high-temperature heat treatment in the atmosphere. The present invention is characterized by applying pure water jet a purification at a jetting pressure of 80 to 100 kg/cm2, followed by solvent vapor phase drying. Next, the present invention will be explained with reference to Examples.

1 to 7 are cross-sectional views showing seven steps in the manufacturing process of a tantalum thin film resistor according to the present invention. First, as shown in FIG. 1, a tantalum-based thin film 2 of about 600A was deposited on a thoroughly cleaned ceramic substrate using the IK sputtering method, and then NiCr7000A and Au3000 were deposited using the same method.
A. Further, a highly conductive metal film 3 is formed by adhering Au to a thickness of about 3 to 4 μm using an electroless plating method. Next, a negative photoresist 4 is applied to a thickness of about 3 μm. Next, as shown in FIG. 2, the highly conductive metal film 3 is selectively etched using a well-known 7-etch resist process to form a desired conductor pattern.

Next, as shown in FIG. 3, a positive photoresist 5 is uniformly coated on the substrate again to a thickness of about 3 μm.

Perform known pre-baking, exposure, development, and post-baking,
Form the desired photoresist pattern.

Next, as shown in FIG. 4, the substrate is treated with hydrofluoric acid and nitric acid.

After removing the tantalum tantalum thin film 2 with an etching solution consisting of an acetic acid mixture, the resist on the pattern is removed using a stripping solution.

Next, as shown in FIG. 5, a strip is formed on the back surface of the group Aν.

N + Cr J' d by Kling method or vacuum evaporation method
Approximately 400 OA of A ++ component film 6 is deposited.

Next, as shown in FIG. 6, a negative type 7. After forming a photoresist layer 7 with a thickness of about 5 μm and sufficiently drying, a negative photoresist 8 of about 4 μm is coated on the metal film 6 on the back side of the substrate, and selectively etched using a known 7-metresist process. , form the desired pattern.

Next, as shown in FIG. 7, after removing the photoresists 7 and 8 on the substrate by a known stripping IF method, pure water jet cleaning at a jet pressure of 80 to 1 kg/cm2 is applied to the substrate surface. 9 to M11, remove foreign matter and resist residue, dry and clean the edges with a solvent, and form the desired Df film pattern on both sides.Then, the substrate is heat treated in the air at 290°C for 7 hours for stabilization. and manufacture thin film circuits.

As described above, when manufacturing a thin film resistor substrate with patterns of different metal film compositions on both sides, when forming the #film pattern on the back side, the photoresist that protects the front pattern is heated several times to bond to the ceramic surface. However, as in the present invention, the 7 otoresist residue on the ceramic surface was removed by high-pressure pure water jet cleaning, and the ceramic was removed by high-temperature heat treatment. There is no discoloration of the surface, making it possible to manufacture high-quality hybrid integrated circuits without damaging the appearance.

[Brief explanation of the drawing]

1 to 7 are cross-sectional views of a hybrid integrated circuit manufacturing process 110 for explaining one embodiment of the present invention. 1...Ceramic substrate, 2...Tantalum thin film, 3--Nicr-Au-Au film, main constituent film, 4, 8-...°°Negative photoresist ,
5...Positive type), Tresist, 6...
NiCr-Pd-Au composition film, 7... mark, etching protective film (negative type) 4-1, resist), 9... pure water jet. Agent Patent Attorney Hi Hara Uchi 1. ．． :

Claims (1)

[Claims] A tantalum-based thin film resistor is formed on an insulating substrate, this thin film resistor portion 1:#c+ the etching retention film formed on the insulating substrate is removed, and further high temperature heat treatment is performed in the atmosphere to stabilize the tantalum thin film resistance. 1. A method of manufacturing a hybrid integrated circuit comprising: performing a heat treatment on the insulating substrate before performing the heat treatment.