JPH0294438A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To effectively form an insulating protective film of high reliability in which deformation caused by stress is little by growing insulating films of different compositions in the same growth vessel, while the composition of reactive gas is changed. CONSTITUTION:A metal layer is stuck on a silicon substrate 1 and worked in a specified pattern, thereby forming a wiring layer 2 composed of the metal layer. Next, in the same growing vessel, an oxide film 3 is formed by using growing gas, and a nitride film 5 is formed by using different growing gas. Thereby, the stress operating between different films is released, and the decrease of reliability caused by the generation of cracks and the like can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and particularly to a method for manufacturing a semiconductor device including a method for forming an insulating protective film.

[Conventional technology]

Conventionally, in the manufacturing method of this type of semiconductor device, the film stress is relatively small and the oxide film is used to capture ionic impurities and protect internal elements and wiring from adverse effects. The nitride film, which has high optical strength, was sequentially formed in growth baths of different equipment, and a protective film was created by laminating the two.

[Problem that the invention seeks to solve]

In the conventional semiconductor device manufacturing method described above, the protective film, which is a stack of insulating films with different compositions, was formed using a dedicated device for forming individual insulating films. There are disadvantages in that cracks and the like occur due to shear strain, reducing reliability, and working efficiency is extremely poor because growth is performed using different equipment.

[Means for solving problems]

The method for manufacturing a semiconductor device of the present invention includes a step of forming a protective film formed by stacking a plurality of insulating films having different compositions on the surface of a semiconductor substrate in the same growth tank, and the protective film has less distortion. form.

〔Example〕

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

FIG. 1 is a sectional view for explaining a first embodiment of the present invention.

The semiconductor device according to this embodiment has a wiring layer 2 made of a metal conductor layer in a predetermined pattern disposed on a silicon substrate 1.
An oxide film 3 for protecting the internal circuit from ionic impurities and a nitride film 5 for protecting the internal circuit from mechanical destruction are sequentially provided on the surfaces of the silicon substrate 1 and the silicon substrate 1.

In the manufacturing method of this embodiment, first, a metal layer is deposited on a silicon substrate 1 by vapor deposition or sputtering, and this is processed into a predetermined pattern by photolithography technology, thereby forming a wiring layer 2 made of the metal layer. form. next,
In the same growth layer, the oxide film 3 with a thickness of 0.75 μm is
i H4 (0,17sfm) and N20 (0,6sem
) and a film thickness of 0.75 μm.
The nitride film 5 of m is made of SiH4<0.17sem) and NH3(
0.35 sfm) using a growth gas.

FIG. 2 is a sectional view for explaining a second embodiment of the present invention.

In the semiconductor device according to this embodiment, the insulating protective film is composed of an oxide film 3', a nitride film 5', and a 5iON-based intermediate film 4' having intermediate properties between the two.

In the manufacturing method of this embodiment, first, an oxide film 3 with a thickness of 0.5 μm is formed on a silicon substrate 1 having a wiring layer 2 on the surface.
' with SiH4 (0,17sfm) and N20 (0,6s
em) After forming the interlayer film 4' with a thickness of 0.5 μm, the flow rate of N20 was gradually lowered from 0.6 sem to Osem while the flow rate of SiH4 (0.17 s e rn ) remained constant. The flow rate of Tsutsukatsu NH is 0.3 from Osem.
The thickness was gradually increased to 5sj'm, and finally the film thickness was 0.
The nitride film 5' of 5,11rn is made of SiH4 (0,17s e
m) and NH3 (0.35sem). ,
In the case of no, the oxide film 3', intermediate film 4', and nitride film 5' are formed in the same growth bath.

As described above, between the oxide film 3', which has a relatively low film stress, and the nitride film 5', which has a relatively high film stress, a 5iON-based intermediate film 4', which has a film stress approximately between the two films, is formed.
By growing the fibers, it is possible to alleviate the stress acting on different crotches and prevent a decrease in reliability due to the occurrence of cracks, etc.

〔Effect of the invention〕

As explained above, according to the present invention, by growing a plurality of insulating films with different compositions in the same growth tank while changing the composition of the reactant gas stepwise or continuously, reliability with less distortion due to stress can be achieved. This has the effect that a highly insulating protective film can be efficiently formed.

1st circle

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of first and second embodiments of the present invention, respectively. 1... Silicon substrate, 2... Wiring layer, 3.3'...
- Oxide film, 4'...intermediate film, 5,5' nitride film.

Claims (1)

[Claims] A semiconductor device comprising the step of forming a protective film formed by laminating a plurality of insulating films with different compositions on the surface of a semiconductor substrate in the same growth tank, and forming the protective film with little distortion. manufacturing method.