JPH03196526A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent peeling and cracks, and to improve the degree of adhesion by depositing an inorganic substance while projecting ion beams and forming an inorganic film for protection. CONSTITUTION:A wiring metallic layer 2 having a specified wiring pattern and an inorganic film 3 are formed onto a semiconductor substrate 1, and flattened by an organic film 4. An inorganic film 5 is formed onto the organic film 4 through an ion beam assisting deposition method. Here, the deposition is performed while the deposited surface is irradiated with ion beams. Consequently, the deposited surface is struck by ions during deposition, and a dense deposit film can be formed. Accordingly, an inorganic film for protecting the organic film having excellent mechanical strength and adhesive properties is formed, and an inter-layer insulating film is not peeled and cracked and multilayer interconnection, in which wiring metallic layers are superposed in any layers, is enabled.

Description

[Detailed Description of the Invention] [Summary] An organic film is formed on a wiring layer to planarize the wiring layer,
Regarding a method for manufacturing a semiconductor device in which a protective inorganic film is formed on an organic film to form multilayer wiring, the purpose of this method is to provide a method for manufacturing a semiconductor device in which peeling and cracking of the interlayer insulating film are less likely to occur. In the method of manufacturing a semiconductor device, the method of manufacturing a semiconductor device includes forming an organic rya on the wiring layer and forming a protective heat mrya on the organic film in order to planarize the wiring layer. It is configured to be formed by an ion beam assisted vapor deposition method in which an inorganic substance is vapor deposited while irradiating an ion beam.

[Industrial Application Field] The present invention is directed to manufacturing a semiconductor device in which a multilayer wiring is formed by forming an organic film on the wiring layer to planarize the wiring layer and forming a protective heat am on the organic film. Regarding the method.

2. Description of the Related Art As LSIs have become more highly integrated and faster in recent years, there has been a demand for multilayer wiring in semiconductor devices.

In a multilayer wiring structure, it is necessary to flatten the interlayer insulating film to prevent the wiring from being cut due to differences in level.

[Prior Art] In a conventional process for forming multilayer interconnects in semiconductor devices, an organic film is used as an interlayer insulating film in order to planarize interconnect layers. However, since the organic film alone has low resistance to various processes such as 0□ plasma treatment, an inorganic film is formed on the v1 film to serve as a protective film.

However, the adhesion of the protective inorganic film to the organic film was poor and it often peeled off. Furthermore, when the wiring is made into a multilayer structure, the thin inorganic film has low mechanical strength and often breaks. Furthermore, due to poor adhesion between the wiring metal and the organic film, the organic film sometimes peeled off from the metal.

[Problems to be Solved by the Invention] As described above, in the conventional process of forming multilayer wiring for semiconductor devices, there was a problem in that the adhesion between the inorganic film and the organic film was poor, resulting in peeling and cracking.

The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a method for manufacturing a semiconductor device in which peeling and cracking of an interlayer insulating film are less likely to occur.

[Means for Solving the Problems] The above object is to form a wiring layer, form an organic film on the wiring layer in order to planarize the wiring layer, and apply a protective thermal V1 film on the organic layer. In the method for manufacturing a semiconductor device, the protective heat tl! ! This is achieved by a method for manufacturing a semiconductor device characterized in that a film is formed by an ion beam assisted vapor deposition method in which an inorganic substance is vapor deposited while irradiating an ion beam.

[Operation] According to the present invention, while irradiating the ion beam! ! Since the protective thermal fi film is formed by the ion beam assisted vapor deposition method of vapor depositing the R substance, it is possible to form an insulating film between the eyebrows without peeling or cracking, and therefore it is possible to form multilayer wiring with good adhesion.

[Example] A method for manufacturing a semiconductor device according to an example of the present invention will be described with reference to FIG.

First, on the semiconductor substrate 1, for example, T i / A u
The wiring metal layer 2 is formed by sputtering. Next, the wiring metal layer 2 is formed into a predetermined wiring pattern by ion milling (FIG. 1(a)).

Next, an inorganic film 3 of, for example, 5iON is formed to a thickness of about 1000 on the entire surface by, for example, a plasma CVD method (Fig. 1(b)), and an R-free film 3 is formed of other materials such as 5iOt or SiN. You may.

Then, for example, silylated polymethylsilsesquioxane (
PMSS (manufactured by Fujitsu)) organic film 4 was spun to 1~
After applying the coating to a thickness of approximately 1 μm using the method and flattening it, approximately 35
Heat at 0°C for about 1 hour to harden (Fig. 1(c)
), the material of the organic film 4 may be polyimide resin or other silicone resin.

Next, an inorganic film 5 of, for example, SiO2 is formed on the organic M4 to a thickness of about 2000 by the ion beam assisted vapor deposition method that is a feature of this embodiment (FIG. 1(d)).

The ion beam assisted vapor deposition method performs vapor deposition while irradiating the surface to be vapor-deposited with an ion beam, and can form a dense vapor deposited film by hitting the surface to be vapor-deposited with ions during vapor deposition.

The ion beam assisted vapor deposition apparatus will be explained using FIG. 2.

The vacuum chamber 20 is evacuated to an appropriate pressure using a vacuum pump connected to the vacuum exhaust port 22. Next, the gas inlet 21
0□ gas flows in from the gas temperature inlet 35, and at the same time Ar
Or 0□ gas flows in.

At this time, the vacuum pump continues to exhaust the vacuum chamber 2.
Make sure to keep the zero pressure constant. A substrate support plate 26 to which a wafer 24 is fixed is provided above the vacuum chamber 20 . The substrate support plate 26 is provided with a rotating shaft 28, and is rotated as necessary.

At the bottom of the vacuum chamber 20 is a deposition source 3 containing materials to be deposited.
0 is mounted, and a shutter 32 is provided above the vapor deposition source 30. Further, an ion source 34 for irradiating an ion beam is provided at the bottom of the vacuum chamber 20.
A shutter 36 is provided above 4.

A method for forming the inorganic film 5 using this ion beam assisted vapor deposition apparatus will be explained.

First, the vacuum chamber 20 is evacuated to, for example, 5 x 10"-'Torr or less using a vacuum pump connected to the vacuum exhaust port 22. Next, 0□ gas is introduced from the gas inlet 21, and at the same time Ar or 02 gas is introduced from the gas inlet 35. At this time, the vacuum pump continues to perform exhaustion to keep the pressure in the vacuum chamber constant.Then, the rotating shaft 28 is rotated to deposit the gas. The substrate support plate 26 on which the wafer 24 to be processed is fixed is rotated.

In this state, the evaporation source 30 was heated by the electron beam and evaporated! ! The material is removed from the vacuum chamber 20 by opening the shutter 32.
release it inside. At the same time, the shutter 3 of the ion source 34
6 is opened to irradiate the wafer 24 with an Ar ion beam. The conditions for the ion beam assisted vapor deposition method at this time are, for example, in an 02 atmosphere of about 250°C, and the gas pressure of the Ar ion beam is 6 x 10-5 Torr;
Adding 02 pressure to this, the gas pressure inside the vacuum chamber 20 is 9X
10-'T.

rr, and the acceleration voltage of the Ar ion beam is 1°25k.
Let it be V. Note that an ion beam of oxygen may be irradiated instead of Ar.

When the inorganic film 5 of desired thickness is formed, the shutter 32
．． 36 is closed to complete the ion beam assisted deposition.

A second wiring metal layer 6 is formed on the dense inorganic film 5 thus formed by the ion beam assisted vapor deposition method. Similarly, an inorganic film 7 and an organic film 8 are formed on the wiring metal layer 6, and the ion beam assisted vapor deposition method is applied to the organic film 8! ! Fl! 1 film 9 is formed. A third wiring metal layer 6 is further formed on this inorganic film 9 (FIG. 1(e)).

In this way, according to the semiconductor device manufacturing method according to this practical example, it is possible to form a very dense film with good adhesion, so it is possible to form a protective inorganic film with excellent mechanical strength and adhesion as a protective film for an organic film. can be formed. Therefore, multilayer wiring in which many wiring metal layers are stacked is possible without peeling or cracking of the interlayer insulating film.

The present invention is not limited to the above embodiments, and can be modified in various ways.
For example, in the above embodiment, the multilayer wiring had three layers, but the wiring had four layers.
It can also be applied to multilayer wiring with more than one layer.

[Effects of the Invention] As described above, according to the present invention, it is possible to form an interlayer insulating film that does not peel or crack, and it is possible to realize a multilayer wiring structure in which many wiring layers are stacked.

[Brief explanation of drawings]

FIG. 1 is a process cross-sectional view of a method for manufacturing a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of an ion beam assisted vapor deposition apparatus. In the figure, 1... Semiconductor substrate 2... Wiring metal layer 3... No RWA 4... Organic film 5... Inorganic film 6... Wiring metal layer 7... No WA 8...・Organic film 9...Inorganic film 10...Wiring metal layer 20...Vacuum chamber 1...Gas inlet 2...Vacuum exhaust port 4...Wiring layer 6...Substrate support plate 8 ... Rotation axis 0 ... Evaporation source 2 ... Shutter 4 ... Ion source 5 ... Gas inlet 6 ... Shutter

Claims (1)

[Claims] 1. To form a wiring layer and planarize the wiring layer,
In the method for manufacturing a semiconductor device in which an organic film is formed on the wiring layer and a protective inorganic film is formed on the organic film, the protective inorganic film is irradiated with an ion beam while depositing an inorganic substance. A method for manufacturing a semiconductor device, characterized in that it is formed by an assisted vapor deposition method. 2. In the method for manufacturing a semiconductor device according to claim 1, in order to improve the adhesion between the wiring layer and the organic film,
A method for manufacturing a semiconductor device, characterized in that the organic film is formed after forming an inorganic film on the wiring layer.