JPH0517867A - Target of sputtering device - Google Patents

Abstract

PURPOSE:To prevent the cracking of the target of a sputtering device by dividing the target to plural pieces, thereby constituting the target. CONSTITUTION:The target 1063 of the sputtering device which releases sputtered particles is constituted by quadrisecting the target along the dividing lines passing the center as shown in Fig(c). A temp. difference generated in the target pieces is decreased and the cracking at the time of the sputtering is prevented. The target of the sputtering device which can form films having a uniform film thickness and film quality on substrates is thus obtd.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a sputtering apparatus for forming a thin film.

[0002]

2. Description of the Related Art Conventionally, a sputtering apparatus has been used as a thin film forming apparatus utilizing the physical sputtering action of a target material by ion bombardment. In recent years, targets having a large area have been used in order to increase production efficiency.

In a sputtering apparatus, a target material is physically sputtered by ion bombardment, and sputtered particles released by the sputtering are used to form a film on a substrate. Therefore, the temperature of the target subjected to ion bombardment rises. . The target is cooled by some cooling means such as a cooling element or a cooling pipe in order to prevent the target temperature from becoming higher than a predetermined temperature, but erosion due to a magnetic field is generated on the surface of the target as the sputtering progresses and the target surface There is a difference in the cooling effect. For this reason, the cooling effect of the cooling means is partially different, and there is a risk that stress due to partial temperature rise will occur and the target itself will crack. This is particularly likely to occur in a target having a large area in order to increase production efficiency.

[0004]

The target of the above-mentioned conventional sputtering apparatus has a risk of breaking the target itself during film formation. When this target is cracked, abnormal discharge occurs and the target becomes a melted material, which is scattered on the substrate, which deteriorates the quality of the film formed on the substrate and stops the discharge. There is a point. Further, there is a problem in that the target is cracked and the sputtered particles do not uniformly scatter even if discharge is performed, resulting in nonuniform film quality and film thickness.

The present invention has been made in view of the above-mentioned problems of the prior art, and it is possible to form a film having a uniform film thickness and film quality on a substrate without cracking during sputtering. The purpose is to realize a target for a sputtering apparatus.

[0006]

A target of a sputtering apparatus of the present invention is a target of a sputtering apparatus which emits sputtered particles and is divided into a plurality of pieces.

In this case, the dividing line dividing the target may be formed by a notch having an angle with respect to the mounting surface of the backing plate on which the target is mounted, and each target piece includes an erosion portion, The target may be divided so that the heat distribution centered on the erosion portion is symmetrical.

[0008]

By dividing the target into a plurality of pieces, the temperature difference generated in each target piece becomes small, and the occurrence of cracks is prevented.

When the dividing line is formed by a cut having an angle with respect to the mounting surface of the backing plate on which the target is mounted, the backing plate is prevented from being sputtered and each target piece includes an erosion portion. When the target is divided so that the heat distribution centering on the erosion portion becomes symmetrical, the expansion direction of the target and the stress due to this are dispersed, so that the effect of preventing the occurrence of cracks is further enhanced. Become.

[0010]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a diagram showing the structure of a sputtering apparatus used in an embodiment of the present invention.

The atmosphere in the film forming chamber 101 is controlled by a gas film forming valve 102, a vacuum valve 104 and an exhaust device 105. In the film forming chamber 101, a resin substrate 103 on which a film forming process is performed and a target 106 are arranged to face each other. The target 106 is supplied with power from a power source 107 provided outside the film formation chamber 101.

The film forming operation in this embodiment is performed as follows.

First, the film forming chamber 101 is evacuated to a predetermined pressure by a vacuum valve 104 and an exhaust device 105, and then a predetermined sputtering gas is introduced from a gas introducing valve 102 and a power source 107 supplies power to a target 106. Then, a thin film is formed on the resin substrate 103 by the sputtering method.

[Example 1] FIG.
The above film forming operation was performed using the targets 106 _{1 to} 106 ₃ having the shapes shown in (a), (b) and (c), respectively.

In FIG. 2, a solid line shows a crack generated by sputtering, and a broken line shows a dividing line of a target divided beforehand.

In the conventionally used integrally-molded target 106 ₁ shown in FIG. 2A, cracks occurred at several places. In FIG. 2 (b) target 106 ₂ which is divided into two by a dividing line passing through the center indicated in, the temperature difference generated in each target piece becomes small, in one crack is generated in the end portion Stayed Figure 2
In the target 106 ₃ which was divided into four by the dividing line passing through the center shown in (c), the temperature difference generated in each target piece was further small, and therefore cracking did not occur.

[Example 2] Dividing lines for dividing the target 106 were formed by notches of two different shapes, and the same sputtering as in Example 1 was performed to compare the results.

As shown in FIG. 3A, the target 10
6 is placed on the backing plate 301 in which the dividing line is formed by the notch 302 perpendicular to the mounting surface, and the target 10 as shown in FIG.
6 has an angle (45 degrees) with respect to the mounting surface of the backing plate 301 on which the backing plate 301 on the parting line portion is located when the target 10
6 and B state in which a dividing line by the notch 303 to be covered with No. 6 was formed, and sputtering with these was performed. The results are shown in Table 1.

[0020]

[Table 1] As is clear from Table 1, the crack shape of the target does not depend on the shape of the notch, but in the A state, the backing plate under the target is sputtered and the film quality on the substrate deteriorates. In the state B, only the target was sputtered, so the film quality on the substrate was good.

[Example 3] The same sputtering as in Example 1 was performed using two types of targets having different dividing lines for dividing the target, and the results were compared.

On the disk-shaped targets 401 and 402 shown in FIGS. 4 (a) and 4 (b), circular erosion as indicated by the one-dot chain line in each figure is generated as the sputtering progresses. . The target 401 shown in FIG. 4A is divided into four parts so that the dividing line intersects the circular erosion portion at right angles, and the target 402 shown in FIG. 4B includes a line that does not relate to the erosion portion. It is divided into 5 by parallel dividing lines.

When sputtering was carried out by using the respective targets divided by the respective dividing lines as described above,
The target 401 did not crack, but the target 402 cracked on the target pieces located at both ends. This is because the temperature difference within the target piece is biased (the temperature near the erosion part is high and the temperature at the outer edge part is low), so the target's expansion direction is also biased in one direction, which increases the stress. This is because it ends up.

As is clear from the above results, the target dividing line is such that each target piece includes an erosion portion, and the target is divided so that the heat distribution centered on the erosion portion is symmetrical. Is desirable. By performing such division, the direction in which the target expands and the stress due to this are dispersed, so that the effect of preventing the occurrence of cracks becomes even stronger.

[0025]

Since the present invention is constructed as described above, it has the following effects.

According to the first aspect of the present invention, by preventing the target from cracking during sputtering, it is possible to form a film having a uniform film thickness and film quality on the substrate.

According to the second aspect of the present invention, it is possible to prevent the backing plate on which the target is placed from being sputtered, so that it is possible to further improve the uniform film quality among the above effects.

According to the third aspect of the present invention, the target is further prevented from cracking.
There is an effect that each of the above effects can be further improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a sputtering apparatus used in an example of the present invention.

FIG. 2 is a diagram for explaining an example of the present invention,
(A) is a conventionally used integrally-molded target (b) is a target divided into two by a dividing line passing through the center according to the present invention, and (c) is a target divided into four by a dividing line passing through the center according to the present invention. It is a figure which respectively shows.

FIG. 3 is a diagram for explaining an example of the present invention,
(A) is a target divided by a cut perpendicular to the mounting surface of the backing plate on which the target is mounted, and (b) has an angle with respect to the mounting surface of the backing plate on which the target is mounted. It is a figure which each shows the target divided | segmented by cutting.

FIG. 4 is a diagram for explaining an example of the present invention,
FIG. 6A is a diagram showing a target divided into four parts so that the dividing line intersects a circular erosion portion at right angles, and FIG. 6B is a diagram showing a target divided into five parts by parallel dividing lines irrespective of the erosion portion. .

[Explanation of symbols]

101 film forming chamber 102 gas film forming valve 103 resin substrate 104 vacuum valve 105 evacuation device 106, 106 _{1 to} 106 ₃ , 401, 402 target 301 backing plate 302, 303 cut

Claims (3)

[Claims] 1. A target for a sputtering apparatus which emits sputtered particles, wherein the target for the sputtering apparatus is divided into a plurality of pieces. 2. The target of the sputtering apparatus according to claim 1, wherein the dividing line for dividing the target is formed by a notch having an angle with respect to a mounting surface of a backing plate on which the target is mounted. Target for sputtering equipment. 3. The target of the sputtering apparatus according to claim 1 or 2, wherein each target piece includes an erosion portion, and the target is divided so that a heat distribution centered on the erosion portion is symmetrical. The target of the sputtering device, which is characterized in that