JPS61265824A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the yield of cracks in the succeeding processes and to improve the reliability of a semiconductor substrate, by alleviating the internal stress of an insulating film by a specified method. CONSTITUTION:On the back surface of a semiconductor substrate, on the upper surface of which an electric wiring and the like are formed, a silicon oxide film 2 is deposited by a vapor deposition method, A semiconductor substrate 1 is mounted on a susceptor 3 kept at 450 deg.C. The semiconductor substrate 1 is curved in a convex shape. SiH4 gas 4 and O2 gas 5 are supplied on the surface of the substrate. Thus a silicon oxide film 6 is deposited as an interlayer insulating film. A resist 7 is applied on the silicon oxide film 6. After burning and solidifying, the silicon oxide film 2 at the back surface is removed. Then the semiconductor substrate 1 tends to return to the original shape by an elastic force. Compression stress is yielded with respect to the silicon oxide film 6, and the internal stress in the silicon oxide film 6 is alleviated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a method for manufacturing an insulating film without generating cracks.

[Conventional technology]

A silicon oxide film, a silicate glass film (PSG film), or the like is usually used as an insulating film in a semiconductor device, and these films are generally formed by atmospheric vapor phase growth.

Conventionally, in the normal pressure vapor phase growth method, a conductor substrate device is placed on a substrate support (susceptor) maintained at an appropriate temperature.
By supplying a reactive gas onto the semiconductor substrate, a silicon oxide film, a P2O film, or the like was deposited on the surface of the semiconductor substrate.

Problems to be solved by the invention C] Silicon oxide film or P deposited by the above-mentioned conventional method
Tensile stress is generated inside the SG film and the like, and cracks occur in subsequent steps due to thermal or mechanical factors. In particular, when the thickness of silicon oxide film or PSG film is increased to improve insulation properties or badge-base susceptibility, etc., the incidence of cracks increases even more. This has had serious drawbacks, such as deterioration of device characteristics due to the intrusion of impurities such as alkali ions and alkali ions, resulting in decreased reliability of semiconductor devices. Furthermore, if the thickness of the silicon oxide film or PSG film is made thinner, the incidence of cracks will decrease, but the insulation between electrical wiring and the passivation property against the intrusion of impurities will decrease, which will also lead to a decrease in reliability. become.

An object of the present invention is to eliminate such drawbacks and provide a highly reliable method for manufacturing an insulating film.

[Means for solving problems]

In the process of depositing an insulating film on one principal surface of a semiconductor substrate by vapor phase epitaxy, the present invention deposits a silicon oxide film on the other principal surface of the semiconductor substrate by vapor phase epitaxy, and then After depositing a desired insulating film on one main surface of the semiconductor substrate,
The method is characterized in that the silicon oxide film deposited on the other main surface is removed.

According to the present invention, the surface side of the semiconductor substrate is bent into a convex shape due to the internal stress of the silicon oxide film deposited on the other principal surface of the semiconductor substrate by vapor phase growth. The insulating film deposited by vapor phase epitaxy on one principal surface of the convexly bent semiconductor substrate is removed by removing the silicon oxide film deposited on the other principal surface. Compressive stress is received from the semiconductor substrate due to the elastic force, reducing the incidence of cracks caused by thermal or mechanical effects in subsequent steps.

〔Example〕

Next, examples of the present invention will be described. 1 to 3 show examples in which the present invention is applied to a method of manufacturing an interlayer insulating film of a semiconductor device.

First, a 2t-1 μm silicon oxide film was deposited on the back surface of the semiconductor substrate l on which electrical wiring etc. were formed by vapor phase growth.
Next, as shown in FIG. 1, the semiconductor substrate 1 is placed on the susceptor 3 maintained at 450°C, and SiH4 gas 4 and 02 gas 5 are supplied to the surface of the semiconductor substrate 1 to form an interlayer insulating film. Then, a silicon oxide film 6 is deposited to a thickness of 1 μm. Here, the silicon oxide film 2 deposited on the back surface of the semiconductor substrate 1 has a thickness of 4×10 dyn/cm at a temperature of 450″C.
Since a tensile stress of 8 degrees is generated, as shown in the figure,
The semiconductor substrate 1 is bent into a convex shape, and a silicon oxide film 6 as an interlayer insulating film is deposited on the surface of the semiconductor substrate l which is bent into a convex shape.

Next, a resist 7 is applied on the silicon oxide film 6 as an interlayer insulating film, and after baking and hardening, the silicon oxide film 2t on the back side is
-Remove with a 7tu acid-based solution (Figure 2).

Next, the resist 7 is removed using an organic solvent (FIG. 3). When the silicon oxide film 2 on the back surface is removed, the semiconductor substrate 1 tries to return to its original shape due to its elastic force, and compressive stress is generated on the silicon oxide film 6 as an interlayer insulating film. As a result, the effective internal stress (tensile stress) of the silicon oxide film 6 as an interlayer insulating film is relaxed,
It is significantly smaller than the conventional method.

〔Effect of the invention〕

As explained above, the present invention significantly reduces the occurrence of cracks due to thermal or mechanical causes in subsequent processes by relaxing the internal stress of the insulating film, and prevents short circuits and cracks between electrical wiring caused by cracks. It is possible to prevent the intrusion of impurities, which has the effect of significantly improving the reliability of the semiconductor device.

The manufacturing method of the present invention is not limited to interlayer insulating films, but can be applied to any insulating film deposited by vapor phase growth.

[Brief explanation of the drawing]

1 to 3 are cross-sectional views illustrating details of the present invention. 1... Semiconductor substrate on which electrical wiring etc. are formed, 2
・・・・・・Backside silicon oxide film by vapor phase growth method, 3
...Susceptor, 4...8iH4 gas, 5...O: gas, 6...Silicon oxide film as interlayer film, 7...・Resist.

Claims (1)

[Claims] In the step of depositing an insulating film on one principal surface of a semiconductor substrate by vapor phase epitaxy, a silicon oxide film is deposited in advance on the other principal surface of the semiconductor substrate by vapor phase epitaxy, and then the semiconductor substrate is deposited by vapor phase epitaxy. 1. A method of manufacturing a semiconductor device, comprising depositing a desired insulating film on one main surface of the semiconductor device, and then removing the silicon oxide film deposited on the other main surface.