JPS6034022A - Manufacture of insulating layer of semiconductor device - Google Patents

Abstract

PURPOSE:To obtain an insulating film having sufficient heat-resistance when the interlayer insulating film between multilayer wirings or the insulating film exposing the surface is to be formed by a method wherein a photosensitive silicon resin composition containing a hydroxy polyladder siloxane, aromatic azide compound and/or an aromatic sulfonyl azide compound is used. CONSTITUTION:When an insulating film is to be adhered on a semiconductor substrate formed with wiring layers, a photosensitive silicon resin composition to be shown next is applied on the wiring layers, and exposure is performed through a mask to be developed. Moreover, heating is applied as occasion demands. At this time, polyladder siloxane shown by the formula I expressing hydrocarbon radicals of one value or substituted hydrocarbon radicals of one value by R1, R2, and an integer by (n), or terminal hydroxy plyladder siloxane shown by the formula II expressing hydrogen radicals by R3, R4, and an integer by (m) is used for one of the composition. Moreover, an aromatic azide compound and/or an aromatic sulfonyl azide compound is used for another composition, and the compositions thereof are mixed to be used.

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing an insulating layer of a semiconductor device.

In the present invention, the insulating layer refers to a passivation film in which the glabellar insulating film and the interlayer insulating film in the multilayer wiring are surface layers.

Conventionally, when forming an insulating layer of a semiconductor device.

For patterning, a method is used in which a photosensitive resist is applied onto each layer, exposed to light, developed, and then each layer is etched. The process using these cysts is very complicated.

It also requires many auxiliary materials.

In order to eliminate this complexity, processes using photosensitive insulating materials have been developed in recent years.

Since the insulating material requires extremely high heat resistance due to its process, 9 photosensitive organic materials such as those normally used in resists cannot be used. Recently, a process using photosensitive polyimide has been developed to solve this problem.
This heat resistance was by no means superior to that of conventional polyimide, and it was accompanied by major restrictions on the semiconductor manufacturing process.

The inventors of the present invention have conducted intensive studies in view of the drawbacks of these conventional methods for manufacturing insulating layers of semiconductor devices, and have arrived at the present invention.

That is, the present invention.

(Al general formula (However, R and 2 are -valent hydrocarbon groups or monovalent substituted hydrocarbon groups, and they may be the same or different (, n is a positive integer) ) and/or the general formula (where R3 and R4 are -valent hydrocarbon groups or monovalent substituted hydrocarbon groups, which may be the same or different (, m is A base material on which a wiring layer is formed is a photosensitive silicone resin composition containing a terminal hydroxypolyladder siloxane represented by (a positive integer) and (B) an aromatic azide compound and /l or an aromatic sulfonyl azide compound. The present invention relates to a method for producing an insulating layer for a semiconductor device, which comprises coating the insulating layer on the insulating layer, exposing it to light through a mask, developing it, and then further heating if necessary.

The photosensitive silicone resin composition used in the production of the insulating layer in the present invention comprises the above-mentioned polyladder siloxane and/or terminal hydroxy polyladder siloxane as a base resin, and an aromatic azide compound and/or an aromatic azide compound as a photosensitive compound. It can be easily obtained by mixing a sulfonyl azide compound in the presence of a suitable solvent. In addition, the above-mentioned photosensitive silicone resin composition has very good heat resistance because the base resin has a ladder-like siloxane structure9. , the thermal decomposition initiation temperature is at most 480 to 50 in the case of polyimide.
It is 1/1550°C or more compared to 0°C. Also,
When polyladder siloxa/ is heated above its thermal decomposition temperature, its side chains will thermally decompose, leaving most of the siloxane skeleton in the main chain as Sigh.Using this property, it can be exposed to light and developed. It is also possible to thermally decompose the photosensitive compound and side chain moieties by subsequent heating to form a patterned 5i02 film. In the case of photosensitive polyimide, if an attempt is made to thermally decompose all the photosensitive compounds, the main chain polyimide skeleton will also be thermally decomposed, making it impossible to use such a method.

Hereinafter, nine aspects of the present invention will be described in detail.

Polyladder siloxane, which is the base resin of the photosensitive silicone resin composition used for manufacturing the insulating layer of the semiconductor device of the present invention, is described in Japanese Patent Publication No. 40-15989, U.S. Patent No. 3.017.386, etc. For example, the general formula 5iC1! It is obtained by polymerizing an intermediate obtained by hydrolyzing trichlorosilane represented by s (where R is a monovalent hydrocarbon group) using an alkaline catalyst such as caustic potash.

Terminal hydroxy polyladder siloxane is disclosed in JP-A-53-8
It can be obtained by the method shown in Publication No. 8099 and the like.

In the above formula showing the above polyladder siloxane or terminal hydroxy polyladder siloxane in the present invention, R1, R2, Rs, R4 are monovalent hydrocarbon groups or monovalent substituted hydrocarbon groups, and they are the same. For example, an alkyl group such as a methyl group, an ethyl group, a propyl group, etc., which may or may not be present.

Although there are aromatic hydrocarbon groups such as phenyl groups and substituted phenyl groups, and halogen-substituted products thereof, in order to obtain an insulating layer with high heat resistance, which is the object of the present invention, polyladder siloxa/film is used. In some cases, phenyl group, or S by thermal decomposition
In the case of forming an iOx film, lower alkyl groups are preferred. In the above formula, n and m are positive integers, which are usually larger than 7 and 5o.

Furthermore, the aromatic azide compounds and aromatic sulfonyl azide compounds used in the photosensitive silicone resin composition generate active species nitrene upon irradiation with light, and this active species undergoes secondary conversion and addition to double bonds. is known to cause hydrogen abstraction reactions. Therefore, these photosensitive compounds added to polyladder siloxane or terminal hydroxy polyladder siloxane cause a difference in solubility in the developing solution between the light-irradiated area and the non-irradiated area through the above reaction, making it difficult to produce a pattern. It becomes possible.

Examples of aromatic azide compounds used in the present invention include:

There are bisazide compounds such as monoazide compounds such as. Further, examples of aromatic sulfonyl azide compounds include bissulfonyl azide compounds such as monosulfonyl azide compounds such as 1 and the like. These photosensitive compounds can be used alone or in combination of two or more.

The photosensitive silicone resin composition used for forming the insulating layer of the semiconductor device of the present invention is usually used in a state in which polyladder siloxane and/or terminal hydroxy polyladder siloxane and a photosensitive compound are dissolved in an appropriate organic solvent. However, the solvent used in this case is preferably one that can dissolve both the polyladder siloxane and/or the terminal hydroxy polyladder siloxane and the photosensitive compound, such as aromatic hydrocarbons such as benzene, toluene, xylene, etc. Ketone solvents such as acetone and methyl ethyl ketone are used. These may be used alone or in combination.

Furthermore, various sensitizers can be used in combination with the above photosensitive silicone resin composition. A sensitizer is a substance that aims to improve photosensitivity by expanding the sensitive wavelength range of a photosensitive compound or efficiently imparting light energy to a photosensitive compound. Benzyl and its derivatives, aryl diazonium salts, anthraquinone and its derivatives, acetophenone or its derivatives, sulfur compounds such as diphenyl disulfide, benzophenone or its derivatives, etc. can be used, and these can be used alone or as a mixture of two or more.

Next, a method for manufacturing an absolute RH of a semiconductor device according to the present invention will be specifically described.

First, a silicon wafer with a wiring layer formed on it.

The photosensitive silicone resin composition described above is applied onto a substrate such as a gallium-arsenide wafer, glass, or ceramic using a spinner or the like. Next, the solvent is removed by drying at a temperature of 80 DEG C. to 150 DEG C., preferably 100 DEG C. to 120 DEG C., for 10 minutes to 60 minutes, preferably 20 minutes to 30 minutes, and then exposed to light through a mask. At this time, the exposure conditions vary depending on the photosensitive compound used, but are not limited to 9%. Thereafter, development is performed using the above-mentioned solvent, dilute alkaline solution, etc. to form a pattern. Development conditions are film thickness and pattern shape.

Although it varies depending on dimensions etc., there is no particular limit.

Next, if necessary, the patterned composition film is heat-treated at an appropriate temperature to form an insulating layer. In order to completely remove the solvent or to form a polyladder siloxane film when terminal hydroxy polyladder siloxane is used, the temperature is 250°C to 500°C, preferably 300°C to
Preferably, the heat treatment is carried out at a temperature of 400°C. Further, in order to thermally decompose the side chains of Polyladder 70xane to form a patterned 95I02 film, it is preferable that K be heat-treated at a temperature of 500°C or higher, preferably 600°C to 800°C.

The present invention will be explained below with reference to Examples.

Example 1 Reference example 1 and Example 1 of Japanese Patent Publication No. 40-15989
This intermediate was then prepared by hydrolyzing phenyltrichlorosilane according to the method.

- Polyphenyl ladder siloxane was produced by dissolving it in dichlorobenzene and polymerizing it using caustic potassium as a catalyst.

1 g of 3.3'-diazide diphenyl sulpon was added to 109 of the thus obtained polyphenyl ladder siloxane (weight average molecular weight 20,000).

A photosensitive silicone resin composition was prepared by dissolving it in Hensen 1009.

Next is the first layer of AI! The above-mentioned photosensitive silicone resin composition was applied onto the silicon wafer on which the wiring layer was formed using a spindle, and dried at 120° C. for 30 minutes to form a 1.0 μm film.

Next, light was irradiated with a Xe-Hg lamp at 5 Q mW/cm" through a quartz mask (DNP Fine Line Test Pattern 1 manufactured by Dai Nippon Printing Co., Ltd.), and then with toluene at 2
After a minute of development, a good pattern was obtained.

Next, this patterned film was heat treated at 400° C. for 1 hour to obtain a patterned insulating layer.

No change was observed in the thus obtained insulating layer even when it was heated at 500° C. when forming a second wiring layer.

Example 2 JP-A-53-8809 using methyltrichlorosilane
Terminal hydroxy polymethyl ladder siloxa produced according to Example 1 of Publication No. 9/(weight average molecular weight 20,000) 1
3 g of 2-(dimethylamino)ethyl paraazidobenzoate was added to 0 g and dissolved in 150 g of toluene to prepare a photosensitive silicone resin composition. This composition was prepared in Example 1.
After exposure and development using the same process as
A heat treatment was further performed at 700° C. for 1 hour to form a patterned insulating layer. The insulating layer thus obtained was completely a SiOx film, and did not impose any thermal restrictions on any subsequent processes.

As shown in the examples above, nine aspects of the present invention.

Since the insulating layer is formed using a photosensitive silicone resin composition that is itself photosensitive and can form a film with sufficient heat resistance, a conventional resist process cannot be used. Therefore, multilayer wiring can be formed very easily.

Claims (1)

[Claims] 1, (A+ General formula (where R1 and the mountain are -valent hydrocarbon groups or monovalent substituted hydrocarbon groups, and these may be the same or different (, n is A polyladder siloxane represented by a positive integer) and /' general formula (where R3 and R4 are -valent hydrocarbon groups or monovalent substituted hydrocarbon groups, and they may be the same or different). A photosensitive silicone resin composition containing a terminal hydroxypolyladder siloxane represented by m (m is a positive integer) and an aromatic azide compound and/or an aromatic sulfonyl azide compound is used to form a wiring layer. 1. A method for producing an insulating layer for a semiconductor device, which comprises coating the insulating layer on a substrate, exposing it to light through a mask, developing it, and further heating if necessary.