JPS63237441A - Semiconductor device - Google Patents

Abstract

PURPOSE:To enhance the close adhesion between a metal layer and an insulating film by a method wherein, after a conductor is formed on a side wall inside a connecting hole, the connecting hole is filled with the metal layer. CONSTITUTION:After an insulating film 2 has been formed in a conductor region 1 formed on a semiconductor substrate, a connecting hole 3 is formed in a desired position by using a lithographic technique and an etching method. Then, a conductor which matches well with the insulating film 2 of, e.g. amorphous silicon or the like is formed inside the connecting hole 3 by a CVD method, a sputtering method or the like; in succession, a prescribed part of this conduc tor is removed by an anisotropic etching method so as to leave the conductor 4 on a side wall of the connecting hole 3. After the connecting hole 3 where the conductor 4 is left has been filled with, e.g., tungsten by thrusting the tung sten selectively by the CVD method or the like, the surface of the insulating film 2 is flattened. After that, a wiring layer or the like is formed on the insulat ing film 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor device, and more particularly to a technique for embedding a hole in a semiconductor device having a connection hole or the like.

[Prior Art] FIGS. 2A and 2B are schematic manufacturing process diagrams of a conventional semiconductor device.

The manufacturing method will be described below with reference to the drawings.

After forming an insulating film 2 by depositing it on a conductor region 1 formed on a semiconductor substrate (not shown), a contact hole 3 is formed at a desired position using lithography technology and an etching method (see FIG. 2A). ).

Next, the connection hole 3 was filled by selectively depositing tungsten, for example, by a CVD method (Second B
(see figure).

Here, the filling with tungsten 5 is to flatten the upper surface of the insulating film 2 to solve the problem of step coverage when an aluminum wiring layer or the like on the upper layer of the insulating film 2 is formed in the connection hole. This is to ensure the connection between the layer and the conductor region 1.

[Problems to be Solved by the Invention] In the conventional semiconductor device as described above, the tungsten 5 and the insulating film 2 are in direct contact with each other, resulting in poor adhesion, and especially when tungsten is used as a barrier metal, the insulating film 2
There was a problem in that a phenomenon was likely to occur when the upper layer aluminum wiring etc. was punched through the interface with the aluminum wire.

The present invention has been made to solve these problems, and provides a semiconductor device that maintains the advantages of filling connection holes with a metal layer such as tungsten and has excellent contact between the metal layer and the insulating film. With the goal.

[Means for Solving the Problems] In the semiconductor device according to the present invention, a conductor is formed on the side wall of the contact hole, and then the contact hole is filled with a metal layer.

[Operation] In the present invention, since the conductor formed on the side wall of the connection hole and the metal layer have good tightness, penetration of the wiring layer at the interface between the metal layers does not cause any phenomenon.

[Example] Figures 1A and 1B are schematic manufacturing process diagrams showing an example of the present invention.

The manufacturing method will be described below with reference to the drawings.

As in the conventional example, after forming an insulating film 2 on a conductor region 1 formed on a semiconductor substrate (not shown), a connection hole 3 is formed at a desired position using lithography and etching. Next, a conductor rcv made of amorphous silicon or the like having good matching with the insulating film 2 is placed in the connection hole 3.
The connection hole 3 is formed by forming it by a p-method, sputtering method, etc., and then removing a predetermined portion by an anisotropic etching method.
The conductor 4 is left on the side wall of the (see 1A-).

For example, tungsten is placed in the connection hole 3 where the conductor 4 remains.
After filling by selective deposition using a VD method or the like, the upper surface of the insulating film 2 is flattened (see FIG. 1B).

Thereafter, the process of forming a wiring layer etc. on the insulating film 2 continues, but the description thereof will be omitted since it is outside the scope of this invention.

In the above embodiment, the conductor is made of amorphous silicon, but the same effect can be obtained if the conductor is made of a high melting point metal, aluminum alloy, or the like and has good compatibility with the insulating film.

Further, in the above embodiments, a connection hole is used as an example, but it goes without saying that the present invention can also be applied to a through hole of a semiconductor device.

[Effects of the Invention] As explained above, this invention forms a conductor with good adhesion to the metal layer on the side wall of the connection hole, thereby preventing the phenomenon of penetration of the wiring layer at the interface between the metal layers and providing stable This has the effect of creating a wiring structure that is

[Brief explanation of the drawing]

1A and 1B are schematic manufacturing process diagrams showing one embodiment of the present invention, and FIGS. 2A and 2B are schematic manufacturing process diagrams of a conventional semiconductor device. In the figure, 1 is a conductor region, 2 is an insulating film, 3 is a connection hole,
4 is a conductor, and 5 is tungsten. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (4)

[Claims] (1) A semiconductor device having a connection hole, comprising: a semiconductor substrate; a conductor region formed on the semiconductor substrate; and an insulating film formed on the semiconductor substrate and having the connection hole corresponding to the conductor region. A semiconductor device comprising: a conductor formed on a side wall within the connection hole; and a metal layer filling the inside of the connection hole except for the conductor. (2) The semiconductor device according to claim 1, wherein the conductor is selected from the group consisting of amorphous silicon, high melting point metal, and aluminum alloy. (3) The semiconductor device according to claim 1 or 2, wherein the connection hole constitutes a through hole. (4) The semiconductor device according to claim 1, 2, or 3, wherein the metal layer is tungsten.