JP3134520B2 - Film forming equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus and a CVD apparatus.
The present invention relates to a film forming apparatus provided with a collimator, such as a (chemical vapor deposition) apparatus.

[0002]

2. Description of the Related Art As the density of semiconductor integrated circuits (ICs) and the like has increased, there has been a demand for finer dimensions and shapes in a manufacturing process.

For example, the connection between multilayer wirings in an IC or the connection between a wiring and a predetermined region of a semiconductor substrate is performed by forming a contact formed in an interlayer insulating layer interposed between wiring layers or a surface insulating layer formed on the semiconductor substrate. In the case of performing through a hole, for example, a metal layer constituting an upper wiring to be connected to the contact hole, for example, AlSi of 1% Si is formed in the contact hole.
Is electrically connected to a lower wiring or a semiconductor region through a contact hole to form a film.

However, in this case, as described above, when the aspect ratio (depth / diameter) of the contact hole is increased due to the miniaturization of the dimensions and shape, the formation of, for example, an Al alloy in the contact hole becomes difficult. It becomes difficult with normal sputtering.

That is, in this case, sputtered Al alloy particles hardly enter the bottom of the contact hole due to a so-called shadowing effect in which incident particles formed by sputtering are deposited on the opening edge or inner peripheral wall of the contact hole. In this case, the coverage of the Al alloy is poor, resulting in defective products such as poor connection and disconnection, and lower reliability.

In order to avoid such inconveniences, for example, high-temperature sputtering, in which an Al alloy is sputtered while heating a film-forming substrate at a high temperature, is being studied.

In this method, an Al alloy is softened or fluidized and poured into a contact hole. In actuality, as shown in a sectional view of FIG. For example, the formation of a Ti base metal film 1 for improving the so-called wetting with the Al alloy is performed in the concave portion 3 formed by the contact hole or the like in the insulating layer 2, and thereafter, the wiring 4 of the Al alloy is formed. .

[0008] However, when forming the base metal film 1 by sputtering or the like, the problem of the shadowing effect described above occurs.

On the other hand, in the Ti base metal film 1, the wiring 4 made of, for example, the Al alloy described above can be formed in a well-wet state without causing so-called voids or voids. To get the effect of pouring into
It must be formed to a certain thickness, for example, 100 nm, and over the entire inner surface of the recess 3 due to the contact hole.

[0010]

Therefore, in the formation of the above-described Ti base metal film, for example, it is desired that the flying direction of the deposit for the film formation be collimated in the axial direction of the contact hole, that is, the concave portion. .

A, B and C in FIG.
Then, the Ti is sputtered, and the incident angle of the sputtered particles (the angle formed with the axis of the concave portion 3) is −60 ° to + 60 °,
This is a simulation of the deposition state of the Ti film in the case of −30 ° to + 30 ° and −10 ° to + 10 °. In this case, the aspect ratio of the concave portion 3 is 2.0, which shows that the smaller the incident angle is, the larger the thickness of the concave portion 3 attached to the inner peripheral wall is.

According to the present invention, for example, collimation is performed to restrict and parallelize the incident direction of incident deposited particles in sputtering or the like of a Ti base metal film into a concave portion due to a contact hole or the like in an insulating film as described above . The purpose of this collimation is to repeatedly use the collimator, and thus to improve the durability.

That is, the present applicant has filed Japanese Patent Application No. 3-10763.
In the No. 5 application, a proposal was made to dispose a collimator between a substrate on which a film is to be formed and a material supply unit in, for example, a CVD apparatus as a film forming apparatus.

As shown in a sectional view of FIG. 6, the collimator is arranged along the direction of the collimator, that is, not shown, for example, along the axial direction of the above-mentioned concave portion 3, that is, along the direction perpendicular to the substrate on which the film is to be formed. A wall 5 for defining a large number of passages is provided.

On the other hand, the sediment particles coming in diverge and enter as shown by the dashed arrows in FIG.
A relatively large amount of sediment particles adhere to both sides of the wall 5 to form a sedimentary layer 6.

The deposited layer 6 tends to be generated asymmetrically with respect to both surfaces of the wall surface 5 and is in a state of temperature rise during operation, so that stress is generated on one surface as shown by an arrow in FIG. 7A. This stress is, for example, a compressive stress that reaches 200 MPa when the deposited layer 6 is Ti.

In this collimator, the above-mentioned deposited layer 6 is formed. If the deposited layer 6 is too thick, it impedes the passage of the target deposited particles or loses the collimating effect. An operation of removing the light from the wall surface 5 is performed.

However, even if the deposited layer 6 is removed, the above-mentioned stress causes deformation to remain on the wall surface 5 as shown in FIG. 7B, which unnecessarily restricts the passage of the deposited particles or reduces the collimating effect. Inhibits and makes it unusable as a collimator. That is, there is an inconvenience that sufficient repetition cannot be performed.

The present invention provides a film forming apparatus such as a sputtering apparatus or a CVD apparatus, in which the collimating effect of the deposited incident particles is ensured and the collimator can be used repeatedly over a long period of time.

[0020]

According to a first aspect of the present invention, as shown in FIG. 1 or FIG. 2, a cross-sectional view of each example, a substrate to be formed and a deposition for forming the film on the substrate. A collimator having wall surfaces arranged in a lattice is arranged at a position separated from the substrate on which the film is to be formed, between the material source supply unit and the collimator, and the collimator is made of a shape memory alloy.

According to the second aspect of the present invention, a similar film-forming substrate 11 is formed.
A collimator 13 made of a superelastic alloy is disposed between the substrate 11 and a deposition material supply unit 12 for forming a film on the film formation substrate 11.

[0022]

According to the above-described apparatus of the present invention, the substrate to be deposited 11
Since the collimator 13 is disposed between the substrate 11 and the deposit material supply unit 12 for forming a film on the substrate 11,
For example, a deposit can be effectively adhered to the inner wall surface of, for example, a concave portion provided on the film-forming substrate 11, that is, a film can be formed.

Since the collimator 13 is made of a shape memory alloy or a superelastic alloy in particular, even if a deposit adheres to the collimator 13, the collimator made of the shape memory alloy has a shape which is previously set to the initial shape. By storing the information, the deposit on the collimator can be removed, and the initial state can be restored again by shape memory or superelasticity.

Therefore, the collimator 13 can be repeatedly used in a good condition.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a film forming apparatus according to the present invention will be described.
An example in which the present invention is applied to a CVD film forming apparatus will be described with reference to FIG.

In this case, there is provided a susceptor 15 for mounting a film-forming substrate 11 provided in the reaction chamber 14, for example, a semiconductor wafer having a concave portion (not shown) such as a contact hole described at the beginning. A deposit raw material supply unit 12, which is a raw material gas inlet in this example, is provided to face this.

A collimator 13 is disposed in the reaction chamber 14 between the susceptor 15 and the source gas inlet, that is, between the substrate 11 on which the film is to be formed and the deposit source 12.

As shown in FIG. 2A, a cross-sectional view of a main part of the collimator 13 and FIG. 2B shows a front view of the main part thereof,
For example, there is provided a disk-like wall 5 as a whole, for example, a grid-like crossing as shown in the figure or a grid-like wall 5 arranged in parallel only in one direction. The wall surface 5 is formed on the substrate 11
A large number of passages 16 are formed in parallel with each other so as to direct the deposited particles toward the substrate 11 with the direction perpendicular to the plate surface.

The collimator 13 is made of a shape memory alloy such as a Cu-Zn-Al alloy or a superelastic alloy such as a Ni-Ti alloy.

In this case, the shape memory is performed in a state where the wall surface 5 forms a passage 16 in which a desired collimating effect can be obtained.

The present invention can be applied to a sputter film forming apparatus, and an example of this case is shown in FIG.

Also in this case, the substrate 11 on which the film is to be formed is
The collimator 13 is disposed between the deposition material supply unit 12 of the film forming material, that is, the target, for example, the Ti target placement unit, so that the direction of the passage and the direction of the wall surface are perpendicular to the surface of the substrate 11. I do.

Reference numeral 21 denotes the cryopump, and reference numeral 22 denotes a heater block.

As described with reference to FIG. 4, the Ti base metal film 1 is sputtered in the concave portion 3 such as a contact hole, and AlSi is deposited thereon, as described with reference to FIG. Examples of forming the wiring 4 and forming TiOxN will be described as Examples 1 and 2.

Example 1 In the sputtering film forming apparatus shown in FIG.
A Ti underlayer was formed using a sputtering apparatus in which a collimator 16 made of a 1 shape memory alloy was arranged. The Ti sputtering conditions were as follows: deposition power 4 kW, sputtering pressure 0.4 P
a, substrate heating temperature 150 ° C, process gas 100scc
m, film forming speed 0.03 to 0.1 μm / mm, film thickness 50 n
m. Then, continuously, the vacuum was not broken and the chamber constituting the sputtering apparatus was transferred to another chamber, where the Al alloy was deposited by high-temperature sputtering.

Example 2 In the sputtering apparatus shown in FIG. 3, a TiON underlayer was formed using a sputtering apparatus in which a collimator 16 made of a Ti—Ni superelastic alloy was arranged. The TiON sputtering conditions are as follows: deposition power 4 kW, sputtering pressure 0.4 Pa, substrate heating temperature 150 ° C., process gas Ar / N ₂ +6 at.
% O ₂ = 40/70 sccm, film formation rate 0.01 to 0.
04 μm / mm and a film thickness of 100 nm. This gives T
The iON could be formed in the concave portion with good coverage.

The film forming apparatus according to the present invention and the film formed by the film forming apparatus are not limited to the above examples.
Various changes can be made according to the purpose of use and the mode.

[0038]

According to the above-described apparatus of the present invention, the collimator 13 is disposed between the film-forming substrate 11 and the deposit material supply unit 12 for film-forming on the film-forming substrate 11. For example, a deposit can be effectively adhered to the inner wall surface of, for example, a concave portion provided in the film-forming substrate 11, that is, a film can be formed.

Since the collimator 13 is made of a shape memory alloy or a superelastic alloy, even if a deposit adheres to the collimator, the collimator made of the shape memory alloy has a shape memory in advance to an initial shape. By doing so, the initial state can be restored again by removing the deposits on the collimator by the shape memory effect or by superelasticity.

Accordingly, the collimator can be repeatedly used in a good condition, and the number of times of exchanging the collimator can be reduced, thereby improving the productivity and reducing the cost of film formation.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a device of the present invention.

FIG. 2 is a sectional view and a front view of a main part of an example of a collimator.

FIG. 3 is a schematic configuration diagram of the device of the present invention.

FIG. 4 is an explanatory diagram of film formation.

FIG. 5 is an explanatory diagram of a film formation state.

FIG. 6 is a sectional view of a collimator.

FIG. 7 is an explanatory diagram of stress and deformation of a collimator.

[Explanation of symbols]

 11 Substrate to be deposited 13 Collimator

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/205 C23C 14/34 C23C 16/44

Claims (1)

(57) [Claims] 1. A substrate is arranged in a grid pattern between a substrate on which a film is to be formed and a deposition material supply unit for forming a film on the substrate on which the film is to be formed. A collimator having a wall surface is disposed, and the collimator is made of a shape memory alloy.