JPH04286351A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To restrain gas from being discharged from a glass film so as to prevent a wiring disconnection caused by corrosion by a method wherein there are provided a process where a gas protective film is formed on an oxide film and the whole surface of an opening region and another process where the gas protective film is removed excluding the side wall of the opening through etching. CONSTITUTION:In this manufacturing method, an oxide film 5, a coated glass film 4, and an oxide film 3 are successively etched in this order using a patterned photosensitive film 6 as a mask to provide openings 7 to an aluminum wiring 2. After the photosensitive film 6 is removed, a gas protective film 8 is formed on the oxide film 5 and all the surface of the opening 7. Then, the gas protective film 8 is removed through dry etching excluding the side walls of the openings 7. In result, gas is prevented from generating from a glass film layer, so that a wiring is protected against corrosion.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a technique for bonding different wiring layers formed on a semiconductor substrate.

0002

2. Description of the Related Art FIGS. 2(a) to 2(e) are cross-sectional views showing the order of steps in a conventional manufacturing method. First, as shown in FIG. 2(a), aluminum wiring 2 is patterned on an insulating film 1.
An oxide film 3 is formed thereon by the CVD method. Next, Figure 2 (
As shown in b), a coated glass film 4 is formed on the oxide film 3. Next, as shown in FIG. 2(c), apply C on the coated glass film 4.
An oxide film 5 is formed again by the VD method.

Next, as shown in FIG. 2(d), using the patterned photosensitive film 6 as a mask, the oxide film 5, coated glass film 4, and oxide film 3 are etched in this order to form an opening on the aluminum wiring 2. form 7. Next, as shown in FIG. 2(e), the photosensitive film 6 is removed.

0004

[Problems to be Solved by the Invention] However, in the conventional method as described above, the glass film layer is exposed on the side wall of the opening, so that gas containing moisture is removed from the exposed glass film layer during heat treatment in a post-process. was generated, and there was a risk that the wiring would be corroded by the components in this gas.

[0005]

[Means for Solving the Problems] The present invention has been made in view of the above points, and the side wall of the opening is covered with a gas protective film.

[0006]

[Operation] By using the method described above, the glass film is not exposed on the side wall of the opening, so that outgassing can be suppressed.

[0007]

[Examples] Examples of the present invention will be described in detail below. First, as shown in FIG. 1(a), an oxide film 3 is formed on an aluminum wiring 2 patterned on an insulating film 1 by a CVD method. Next, as shown in FIG. 1(b), a coated glass film 4 for planarization is formed on the oxide film 3.

Next, as shown in FIG. 1(c), an oxide film 5 is again formed on the coated glass film 4 by the CVD method. Next, using the patterned photosensitive film 6 as a mask, as shown in FIG. Form. Next, as shown in FIG. 1E, after removing the photosensitive film 6, a gas protective film 8 is formed on the entire surface of the oxide film 5 and the opening 7 by plasma CVD. next,
As shown in FIG. 1(f), the nitride film 8 is removed by dry etching except for the side walls of the opening 7.

[0009] As the gas protection film, it is preferable to use a nitride film or an oxynitride film.

0010

Effects of the Invention According to the present invention, in the manufacturing process of VLSIs that require miniaturization and high integration, by using a glass film, it is possible to achieve flattening of the interlayer insulating film of multilayer wiring. Since the glass film is not exposed in the contact hole for joining the multilayer wiring by using a gas protective film, degassing is suppressed and disconnection defects due to corrosion of the wiring are eliminated. Therefore, reliability of the semiconductor device is improved.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the order of steps in the manufacturing method of the present invention.

FIG. 2 is a cross-sectional view showing the order of steps in a conventional manufacturing method.

[Explanation of symbols]

1 Insulating film 2 Aluminum wiring 3 Oxide film 4 Coated glass film 5 Oxide film 6 Photosensitive film 7 Opening part 8 Gas protective membrane

Claims (3)

[Claims] 1. A step of forming a desired element on the main surface of a semiconductor substrate and forming a first oxide film on the entire surface, and forming a coated glass film on the entire surface of the oxide film to smooth the uneven parts. a step of forming a slope, a step of forming a second oxide film on the glass film, a step of opening holes in desired portions of the first and second oxide films and the glass film, and a step of forming a hole on the oxide film. A method for manufacturing a semiconductor device, comprising the steps of: forming a gas protective film over the entire surface of the opening region; and removing the gas protective film by etching except for the sidewall of the opening. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the gas protection film is a nitride film. 3. The method of manufacturing a semiconductor device according to claim 1, wherein the gas protection film is an oxynitride film.