JP2743366B2 - Method for manufacturing multilayer wiring structure using resin interlayer film - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a multilayer wiring structure using a resin interlayer film, and more particularly to a multilayer wiring structure using a resin interlayer film having enhanced moisture resistance. And a method for producing the same.

[Conventional technology]

Conventionally, multilayer wiring using a resin film as an interlayer insulating film is
As a resin film, a polyimide resin having excellent heat resistance, that is, a film formed by heating and polymerizing a polyamic acid solution formed by reacting an aromatic tetracarboxylic dianhydride and an aromatic diamine in equimolar amounts is used. .

[Problems to be Solved by the Invention] However, when the above-described polyimide resin is formed on the polyimide resin film by forming an inorganic film such as a silicon nitride film by plasma enhanced chemical vapor deposition as a passivation film to enhance moisture resistance, Cracks are generated in the inorganic film (Semiconductor World, October 1986, p. 40) and wrinkles are generated, and there is a problem that reliability of moisture resistance is remarkably deteriorated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a multilayer wiring structure using a resin interlayer film in which the above problem is solved, that is, the moisture resistance is enhanced.

[Means for solving the problem]

In the method for producing a multilayer wiring structure using a resin interlayer film according to the present invention, the interlayer insulating resin film is preferably made of an aromatic tetracarboxylic dianhydride represented by the following formula (1) and a diamine represented by the formula (2): And a solution containing a polyamic acid silicon-type intermediate formed by mixing and reacting an aminosilicon compound represented by the formula (3).
After heat treatment, and after selectively forming the final metal wiring on the interlayer insulating film, 300 ~ 450 ℃
Heat treatment at a temperature of 2 ° C., and two layers of a plasma-enhanced chemical vapor deposition silicon nitride film, a plasma-enhanced chemical vapor deposition silicon oxynitride film, a plasma-enhanced chemical vapor deposition silicon oxynitride film, and a plasma-enhanced chemical vapor deposition silicon nitride film It is characterized in that a cover film is formed by a film.

In the formulas (1) to (3), R ¹ represents a tetravalent carbocyclic aromatic group, and R ² represents an araliphatic having 6 to 30 carbon atoms or
A carbocyclic aromatic group having 6 to 30 carbon atoms, R ³ and R ⁴ are each independently an alkyl group having 1 to 6 carbon atoms or a phenyl group,
K is a value of 1 ≦ K ≦ 3.

Furthermore, the above-mentioned plasma enhanced chemical vapor deposition silicon nitride film or plasma enhanced chemical vapor deposition silicon nitride film is characterized in that its internal stress is a compressive stress and its magnitude is 10 ⁹ to 10 ¹⁰ dyne / cm ² . .

According to the present invention, by incorporating an SiO component into a resin film used as an interlayer film, the internal stress is a compressive stress as a cover film on the resin film, and the magnitude thereof is 10%.
⁹ to 10 ¹⁰ dyne / cm ² of a plasma enhanced chemical vapor deposition silicon nitride film, a plasma enhanced chemical vapor deposition silicon oxynitride film, or a plasma enhanced chemical vapor deposition silicon nitride film and a plasma enhanced chemical vapor deposition silicon nitride film. Cracks and wrinkles do not occur when a two-layer film is formed.

〔Example〕

Next, the present invention will be described based on embodiments with reference to the drawings.

The coating solution for forming the resin film used in this example was an aminosilicon compound. Is represented by Diaminodiphenyl ether was used as a diamine using P-aminophenyltrimethoxysilane, and benzophenonetetracarboxylic dianhydride was used as an aromatic tetracarboxylic dianhydride. The molar concentration of P-aminophenyltrimethoxysilane was 40%. . Also, using dimethylacetamide as a solvent, the viscosity of the solution was 30.
It was 0cm · poise.

Example 1 In this example, a resin film based on the present invention was formed on a silicon substrate, and a plasma-enhanced chemical vapor deposition silicon nitride film was formed on the resin film to determine whether cracks and wrinkles occurred. Examined. As a comparison, a polyimide resin film containing benzophenonetetracarboxylic dianhydride and diaminodiphenyl ether without P-aminophenyltrimethoxysilane was used.

A resin film based on the present invention and a polyimide film are formed on a silicon substrate to a thickness of about 1.5 μm by applying the same heat treatment, and the final heat treatment is performed at 350 ° C., 400 ° C., 450 ° C. for 1 hour in a nitrogen gas atmosphere. By changing the gas flow ratio on the sample by plasma chemical vapor deposition, the internal stress is a compressive stress, and the size is 1 × 10 ⁹ to 1 × 10
¹⁰ dyne varied between / cm ^2, about the thickness at a temperature of 300 ° C. 1.0 micron
Table 1 shows the results of examining the presence or absence of cracks and wrinkles when the m-type silicon nitride film was formed. From the figure, when the resin film according to the present invention is used, the final heat treatment temperature is 350 ° C,
At 400 ℃ and 450 ℃, the internal stress of silicon nitride film is 1 × 1
No cracks or wrinkles occurred between ^{09 and} 1 × 10 ¹⁰ dyne. However, in the case of the polyimide resin film, cracks did not occur, but wrinkles occurred.

Example 2 FIGS. 1A to 1G are cross-sectional views showing steps in the case of forming a two-layer Al wiring structure having enhanced moisture resistance according to an example.

In FIG. 2A, a semiconductor element active portion is formed,
Further, a phosphorus glass film 204 formed by chemical vapor deposition is formed on the surface of the element substrate 201 on which the polysilicon electrodes 203 and 203 'are formed via a phosphorus glass film 202 formed by chemical vapor deposition, and the lithography and dry etching are performed in the same manner. As shown in (b), first openings 205 and 20 for establishing electrical continuity between the polysilicon electrode and the first aluminum wiring.
Then, an aluminum film having a thickness of about 1 μm is formed by sputtering, and first aluminum wirings 206 and 206 ′ are formed by photolithography and dry etching as shown in FIG. Next, as shown in FIG. 3D, the coating solution of the present invention was applied at 2000 revolutions per minute for 30 minutes.
Spin coating at 100 ℃ for 1 hour and 240 ℃ for 30 minutes
Heat treated at 400 ° C for 1 hour in nitrogen gas atmosphere, about 1.5μm
A thick resin film 207 is formed. Subsequently, a titanium metal film of about 0.1 μm is formed by a sputtering method as an etching mask for the resin film, and the titanium metal film and the resin film are etched by known photolithography and dry etching, and then the titanium metal used as the etching mask is removed. As a result, second openings 208 and 208 'for establishing electrical continuity between the first aluminum wirings 206 and 206' and the second aluminum wiring are provided as shown in FIG. Next, an aluminum film having a thickness of about 1 μm is formed by a sputtering method, and second aluminum wirings 209 and 20 are formed by photolithography and dry etching as shown in FIG.
By forming 9 ', a two-layer aluminum wiring structure is formed.

Next, to remove moisture absorbed by the resin film,
After heat treatment in nitrogen gas atmosphere at ℃ for 15 minutes, the same figure (g)
As shown in the figure, 350
After forming a silicon nitride film 210 having a thickness of about 1 μm at a temperature of about 1 μm and a compressive stress whose size is 3 × 10 ⁹ dyne / cm ^2, it is separated from the outside of the chip by photolithography and dry etching. The silicon nitride film on the aluminum pad for electrical conduction is removed.

Through the above steps, a two-layer aluminum wiring structure having enhanced moisture resistance is formed.

When the moisture resistance test was performed on the two-layer aluminum wiring structure with enhanced moisture resistance formed in this example in saturated steam at 150 ° C. and 2 atm for 300 hours, there was no corrosion of the aluminum wiring. .

Similar effects were obtained when a silicon oxynitride film having a compressive stress of 2 × 10 ⁹ dyne / cm ² was used as the cover film, and when a two-layer film including the silicon oxynitride film was used.

〔The invention's effect〕

As described above, in the resin film according to the present invention, the internal stress is a compressive stress on the resin film, and the size thereof is 10%.
^{9 ~10 10 dyme} / cm ² in a plasma chemical vapor silicon nitride film due to the growth, or silicon oxynitride film, or cracks to form a two-layered film of a silicon nitride film and a silicon oxynitride film, wrinkles occur Therefore, there is an effect that the moisture resistance reliability can be improved. Accordingly, the multilayer wiring structure using the moisture-resistant interlayer resin obtained by the present invention has a great effect on a semiconductor device which is required to have high moisture resistance and high reliability.

[Brief description of the drawings]

1 (a) to 1 (g) are cross-sectional views showing steps in the case of forming a two-layer aluminum wiring structure with enhanced moisture resistance according to another embodiment of the present invention. 201: Element substrate, 202: Phosphor glass film, 203, 203 '
... Polysilicon electrode, 204 ... Phosphor glass film, 205,205 '
... first opening, 206, 206 '... first aluminum wiring, 207 ... resin film based on the present invention, 208, 208' ... second
Opening, 209, 209 '... second aluminum wiring, 210 ...
... Silicon nitride film.

Claims (2)

(57) [Claims] 1. An interlayer insulating film comprising an aromatic tetracarboxylic dianhydride represented by the following formula (1), a diamine represented by the formula (2), and an amino represented by the formula (3): It is formed by applying and heat-treating a solution containing a silicon polyamic acid type intermediate formed by mixing and reacting with a silicon compound. Subsequently, a final metal wiring structure is formed on the interlayer insulating resin film. After selective formation, 30
Heat-treated at a temperature of 0 to 450 ° C. to form a plasma-enhanced chemical vapor deposition silicon nitride film, a plasma-enhanced chemical vapor deposition silicon oxynitride film, or a plasma-enhanced chemical vapor deposition silicon oxynitride film; A method of manufacturing a multilayer wiring structure using a resin interlayer film having enhanced moisture resistance, comprising forming a cover film by a two-layer film with a film. (In the formulas (1) to (3), R ¹ represents a tetravalent carbocyclic aromatic group, and R ² represents an aromatic group having 6 to 30 carbon atoms or a carbon ring having 6 to 30 carbon atoms. R ³ and R ⁴ are independently an alkyl group having 1 to 6 carbon atoms or a phenyl group, and K is 1 ≦
K ≦ 3. ). 2. A method of manufacturing a multilayer wiring structure using a resin interlayer film according to claim 1, wherein a plasma-enhanced chemical vapor deposition silicon nitride film formed on said multilayer wiring structure, The internal stress of a vapor-grown silicon oxynitride film is a compressive stress and its magnitude is 10 ⁹ to 1
0 ¹⁰ dyne / cm ² , a method for manufacturing a multilayer wiring structure using a resin interlayer film.