JPH05320893A - Thin film deposition system - Google Patents

Abstract

PURPOSE:To improve the reliability of products by installing a slit vertically inclined from a substrate between the substrate and a target and turning the substrate and/or slit to form a uniform film inside micropores on the substrate. CONSTITUTION:This system consists of a target 1, a slit 3, a device for turning the substrate 2 and/or slit 3, etc. The target 1 is formed with a raw material for a thin film and installed in the place opposite to the substrate 2. The slit 3 is installed between the substrate 2 and the target 1 and sputter atoms in the inclined direction are passed through the slit. The sputtering atoms having an incident angle equal to the inclined angle of the slit 3 are passed through the slit 3 to reach the substrate 2, and further, since the sputter atoms reach the whole area of the side of the micropores by turning the substrate 2 and/or slit 3, a uniform film is formed inside the micropores.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus.

[0002]

2. Description of the Related Art FIG. 5 is a sectional view showing the structure of a conventional thin film forming apparatus. This thin film forming apparatus is described on page 150 of "Sputtering Phenomenon" (The University of Tokyo Press, 1984). It is a thing. In FIG. 5, 1 is a target which is a film forming material, 2 is a substrate on which a film is formed, 4 is a film forming chamber, 5 is a vacuum pump, and 6 is a gas supply pipe.

Next, a film forming method using this thin film forming apparatus will be described. First, the film forming chamber 4 is set to the vacuum pump 5
After the gas is exhausted to about 10 ⁻⁶ Torr or less by the above, a discharge gas containing Ar is introduced into the film forming chamber 4 through the gas supply pipe 6, and the pressure in the film forming chamber 4 is adjusted to about 10 ⁻³ Torr. In this state, a predetermined voltage is applied between the target 1 and the substrate 2 to ionize the discharge gas to generate plasma and generate Ar ⁺ ions.

At this time, Ar ⁺ is attracted by the electric attraction while accelerating toward the target 1 which is the cathode, and collides with the target 1. The collision of Ar ⁺ causes atoms on the surface of the target 1 to be ejected from the target 1. This phenomenon is a sputtering phenomenon, and the atoms of the target 1 repelled by this sputtering fly toward the opposing substrate 2, and the flying atoms adhere and deposit on the substrate 2 and, as a result, on the substrate 2. Then, a thin film made of the material of the target 1 is formed.

[0005]

By the way, the atoms of the target 1 repelled by sputtering fly while colliding with the repelled atoms and the molecules and ions of the gas present in the film forming chamber 4. As it goes on, its flight direction changes variously. FIG. 6 shows that the target 1 is formed by sputtering on the portion of the minute hole 7 formed on the substrate 2.
(FIG. 5) is a cross-sectional view showing a state in which the sputtered atoms 8 that have been repelled are deposited and a thin film 9 is formed.
As shown in FIG. 6, when the sputtered atoms 8 jumping out of the target 1 reach the substrate 2, they are incident at an incident angle having an arbitrary distribution. Here, the incident angle means the substrate 2
And the incident direction of the sputtered atoms 8 on the substrate 2 is shown.

In the conventional thin film forming apparatus, the sputtered atoms 8 that can reach the bottom of the micropore 7 are limited to those having an incident angle of 90 ° with respect to the bottom surface of the micropore 7, and reach the side surface of the micropore. The sputtered atoms 8 are limited to those whose incident angle is not 90 ° with respect to the surface of the substrate 2. On the other hand, the sputtered atoms 8 reach the surface of the substrate 2 other than the minute holes 7 regardless of the incident angle. Therefore, in the film formation on the substrate 2 by the conventional thin film forming apparatus, the film formed on the surface of the substrate 2 becomes thicker than the film formed on the side surface and the bottom surface inside the minute holes 7 of the substrate 2, and the minute holes 7 are formed. The value (coverage) obtained by dividing the minimum film thickness of the thin film 9 formed inside by the maximum film thickness of the thin film 9 formed on the flat portion of the substrate 2 other than the minute holes 7 becomes a low value, and the reliability of the product is improved. Significantly inhibits sex.

The present invention has been made to solve the above problems, and it is an object of the present invention to obtain a high coating rate in film formation on micropores or the like during film formation by sputtering.

[0008]

SUMMARY OF THE INVENTION A thin film forming apparatus of the present invention includes a target installed at a position facing a substrate on which a thin film, which is a raw material of a thin film to be formed, and a substrate installed between the substrates. And a slit having an inclination with respect to a direction perpendicular to the surface of the substrate, and the substrate or the slit is rotatable.

[0009]

Function: Sputtered atoms having an incident angle similar to the tilt angle of the slit can reach the substrate through the slit. Further, by rotating either the substrate or the slit to uniformly form a film in the micropores, sputtered atoms can reach the entire side surface of the micropores on the substrate.

[0010]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the structure of a thin film forming apparatus which is an embodiment of the present invention. In FIG. 1, reference numeral 3 is a slit, and the others are similar to those of the thin film forming apparatus of FIG. Further, FIG. 2 shows the inclination of the slit 3 and the corresponding microscopic holes 7.
It is sectional drawing which shows the coating condition of the board | substrate 2 which has.

As described in the conventional example, the sputtering atom 8 is generated by the sputtering phenomenon generated by the plasma of the discharge gas introduced from the gas supply pipe 6 into the film forming chamber 4 which is evacuated by the vacuum pump 5 and has a low pressure. It is repelled from the target 1 and flies in various directions by collision with the ions of the discharge gas and the sputtered atoms 8 in the film forming chamber 4. However, due to the slit 3 having an inclination with respect to the direction perpendicular to the plane of the substrate 2, only the sputtered atoms 8 whose incident angle to the substrate 2 is approximately the same as the inclination angle of the slit 3 reach the substrate 2. Here, as shown in FIG. 2, when the sputtered atoms are deposited on the portion of the minute hole 7 on the substrate 1, the slit 3
2 is located at the position shown in FIG.
A film is easily formed on the left side surface of the
A thin film 9a is formed on the portion.

Next, the slit 3 is rotated and the slit 3 shown in FIG.
In the case of the arrangement as shown in (b), a film is likely to be formed on the right side surface of the micropore 7, and 9b in addition to the thin film 9a is formed in the micropore 7 portion of the substrate 2. Therefore, by rotating the slit 3 during the film formation, the slits shown in FIG.
As shown in, the film can be uniformly formed on the side surface and the bottom surface in the micropore 7. At this time, sputtered atoms 8 having a small incident angle that cannot reach the inside of the minute hole 7 are captured by the slit 3 and do not reach the substrate 2, so that they reach the inside of the minute hole 7 as compared with the case without the slit 3. The difference between the number of sputtered atoms 8 and the number of sputtered atoms 8 reaching the flat portion of the substrate 2 other than the minute holes 7 is reduced, that is, a film having a high film coverage is obtained.

By the way, when the slit 3 is angled too much or the minute holes 7 are small in diameter and deep, the sputtered atoms 8 do not reach the bottom of the minute holes 7 as in the thin film 9c shown in FIG. 2 (c). A film is not formed on the bottom of the minute hole 7.
Therefore, the inclination angle of the slit 3 is tan ^{-1 when} the aspect ratio (hole depth / hole diameter) of the minute holes 7 is R.
R is preferred.

(Embodiment 2) In the above embodiment, the case where the slit 3 is rotated has been described, but the substrate 2 may be rotated and the same effect as that of the embodiment 1 is obtained. (Embodiment 3) By the way, many sputtered atoms that are repelled by the sputtering phenomenon from the target 1 jump out perpendicularly to the target 1, so that the target 1 is perpendicular to the inclination of the slit 3 as shown in FIG. Alternatively, the sputtered atoms 8 vertically projected from the target 1 may reach the substrate 2. (Embodiment 4) Further, as shown in FIG. 4, the slit 2 may not be inclined and the substrate 2 may be inclined so that the sputtered atoms vertically ejected from the target 1 may not be captured by the slit 3. In Example 3 and Example 4, among the sputtered atoms 8 protruding from the target 1, those sputtered out vertically from the target 1 having the largest amount thereof are effectively used, so that the film formation rate is improved. is there.

[0015]

As described above, according to the present invention, the flight direction of sputtered atoms is controlled by the slit,
Moreover, since the substrate is rotated to form a film, it is possible to perform uniform film formation even on a substrate having micropores, which has the effect of improving the reliability of the product.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the configuration of a thin film forming apparatus that is an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a film formation state of minute holes by the thin film forming apparatus of one embodiment of the present invention.

FIG. 3 is a sectional view showing a positional relationship among a target, a slit and a substrate showing another embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a positional relationship among a target, slits, and a substrate according to another embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a configuration of a conventional thin film forming apparatus.

FIG. 6 is a cross-sectional view showing a film formation state of minute holes by a conventional thin film forming apparatus.

[Explanation of symbols]

 1 target 2 substrate 3 slit 4 film forming chamber 5 vacuum pump 6 gas supply pipe

Claims (2)

[Claims] 1. A target, which is a raw material of the thin film, placed at a position facing a substrate on which a thin film is formed, and a target placed between the substrates and a direction perpendicular to a surface of the substrate. And a slit for passing sputtered atoms in a tilted direction, and at least one of the substrate and the slit is rotated. 2. The thin film forming apparatus according to claim 1, wherein the substrate and the target are arranged to be inclined with respect to each other.