JPS6037751A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent disconnections and short-circuits by realization of the flattening of the surface of an interlayer insulation film by a method wherein the insulation film is put in a multilayer structure by the bias sputtering technique. CONSTITUTION:An oxide film 3a doped with phosphorus and having a sufficiently low viscosity is grown in chemical vapor phase, and next an oxide film 3b is deposited in superposition by the bias sputtering method. Since bias sputtering etches an oxide film being deposited while the film is deposited, selection of a condition of reverse bias enables to deposit substances while the surface is flattened. Otherwise, it is also available that an oxide film 3c of a sufficiently low viscosity is deposited in the atmosphere of phosphorus by sputtering, and that a non-doped oxide film 3d is successively deposited by the sputtering method wherein a reverse bias is applied. This construction enables to obtain the interlayer insulation film whose surface is flattened, causing no disconnections and short-circuits in the wiring formed in the upper layer thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a semiconductor device, and particularly to a method for forming an interlayer insulating film in a semiconductor device.

[Prior art]

FIG. 1 shows the main structure of a semiconductor device including a glabella insulating film obtained by a conventional manufacturing method. That is,
In the conventional method shown in FIG. 1, an interlayer insulating film (
3) is deposited, and this interlayer insulating film (
3) A second wiring material layer (not shown) is further formed on top of the first wiring material layer (2).
Because of the presence of this, the steeper the step on the surface of the interlayer insulating film (3), the steeper the step in the second wiring I material layer above it, leading to defects such as disconnections and short circuits. It was easier.

Therefore, in conventional methods, for the purpose of flattening the surface, a method is used in which a low-viscosity insulating film 2, for example, an oxide film mixed with phosphorus, is formed by chemical vapor deposition. Even in the conventional method, there is a problem in that it is still not possible to achieve a satisfactory leveling in areas with large step differences due to the miniaturization of patterns.

[Summary of the invention]

In view of these drawbacks of the conventional method, the present invention is designed to realize a flat surface of the interlayer insulating film by forming the υ interlayer insulating film into a multilayer structure using bias sputtering technology.

[Embodiments of the invention]

2 and 3 for each different embodiment of this invention.
This will be explained in detail with reference to the drawings.

FIG. 2 shows the structure of the main part including the interlayer insulating film of a semiconductor device obtained by the method of the first embodiment shown in correspondence with FIG. 1. The same reference numerals in these figures indicate the same or corresponding parts. In the method of this first embodiment, an insulating film 2 having a sufficiently low viscosity, for example, phosphorus, is first formed as the first interlayer insulating film (3). An oxide film (3a) doped with oxide is formed by chemical vapor deposition, and then an insulating film 2, such as a molten oxide film (3b), is deposited thereon by bias sputtering to form an interlayer insulating film (3). ) is formed in multiple layers. However, since this bias sputtering etches the deposited insulator while depositing, it is possible to deposit the material while flattening the surface depending on the reverse bias conditions.

In addition, FIG. 3 shows the same main part configuration according to the method of the second embodiment. In the method of the second embodiment, the first interlayer insulating film (3) is first oxidized by sputtering in a dangerous atmosphere. After depositing an insulating film with sufficiently low viscosity, such as film (3o), by sputtering, an insulating film 2, such as a non-doped oxide film (3d), is subsequently deposited by bias sputtering with a reverse bias applied. The feature is that the interlayer insulating film (3) can be similarly formed in multiple layers by depositing the interlayer insulating film (3). That is, in this case as well, the pacifying characteristic of the bias sputtering method is utilized, as in the method of the first embodiment.

In addition to the methods of each of the embodiments described above, it is of course possible to change the order of forming the multilayer structure.

〔Effect of the invention〕

As described in detail above, according to the method of the present invention, the insulating film between the eyebrows can be made flat by forming a multilayer pattern of oxide film, insulating film, etc. by using the bias snow ivy technique. This can easily prevent failures such as disconnections and short circuits in the wiring layer pattern formed in the upper layer.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a schematic diagram of the main parts including the interlayer insulating film of a semiconductor device obtained by the conventional method, and FIG.
Figures 3 and 3 are cross-sectional views showing the general configuration of the main parts of the above obtained by different embodiment methods of the present invention, (1)... semiconductor substrate, (2)... First wiring material layer, C)... interlayer insulating film, (3a), (3
b)-(3c), (3d)...Oxide film forming a multilayer 4-row structure. Continued from page 1 □ 0 Inventor: Makoto Sato - Inside the Eye Research Institute, Mizuhara 4-chome, Itami City

Claims (3)

[Claims] (1) A method for manufacturing a semiconductor device having an interlayer insulating film, characterized in that the interlayer insulating film is formed by a bias sputtering method to have a multilayer structure of insulating films with low viscosity. (2) After forming a low-viscosity insulating film such as a phosphorous-doped oxide film by chemical vapor deposition, an insulating film such as an oxide film is deposited on top of it by bias sputtering. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the glabella insulating film is formed in a multilayer structure. (3) Low viscosity of sputtered oxide films in phosphorous atmosphere
After depositing the edge film by sputtering, an insulating film such as a non-doped oxide film is deposited on top of it by bias sputtering with reverse bias, forming an interlayer insulating film in a multilayer structure. A method for manufacturing a semiconductor device according to claim 1, characterized in that: