JPH05267171A - Magnetron sputtering device - Google Patents

Abstract

PURPOSE:To enhance the usage effect of targets, extend the cycle of target replacement and the productivity of a deposition process by consuming the targets equally as much as possible. CONSTITUTION:A pair of magnet units 12 and 13 having a symmetric magnetic pole layout are installed at a symmetric position, facing a target, which forces their lines of magnetic force to repel each other. Therefore, a parallel line portion of magnetic force is formed in a wide area near the surface of the target, which makes it possible to consume the target equally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetron sputtering device.

[0002]

2. Description of the Related Art A magnetron sputtering apparatus that promotes the movement of electrons by applying a magnetic field to plasma has been widely used because it greatly increases the deposition rate. The structure and operation of the conventional magnetron sputtering apparatus will be described with reference to FIG. First, the sputtering apparatus itself includes a substrate (silicon substrate or the like) 10 on which vapor deposition is to be performed.
And a target 11 facing it. The periphery of both is filled with an inert gas (usually Ar gas) of low pressure (about 1 Pa), and this is turned into plasma by discharge. The voltage applied between the substrate 10 and the target 11 accelerates the ions in the plasma to collide with the target 11 and cause the target material to fly out. The target material that has jumped out reaches the substrate 10 and is deposited there.

The magnetron sputtering apparatus is shown in FIG.
As shown in, the magnet unit 12 is provided on the back surface side of the target 11 and a magnetic field is applied to the inert gas plasma. This accelerates the movement of electrons in the plasma to increase the plasma concentration, so that the target 11 is sputtered more and the deposition rate is increased.

[0004]

As shown in FIG. 2A, the magnet unit 12 normally has a large number of magnets 13 connected by a yoke 14 so as to apply a magnetic field to as much of the flat target 11 as possible. Is configured. However, even if the distance between the magnets 13 is made considerably small, the lines of magnetic force between the magnets 13 have a mountain shape having a peak in the middle as shown in FIG. The magnetic field most activates the movement of the electrons in the plasma because the direction of the lines of magnetic force is orthogonal to the direction of the electric field (vertical direction in FIG. 2A). In the conventional magnetron sputtering apparatus, such a portion is limited to a relatively narrow portion between the adjacent magnets 13. Therefore, target 11
The target 11 is shown in FIG.
As shown in (b), it is consumed extremely rapidly locally, and becomes unusable with many unused parts left. This is not only a waste of the target 11, but also a problem that the productivity of the vapor deposition process is reduced because the cycle of target replacement is shortened.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a magnetron sputtering apparatus in which a target is consumed as uniformly as possible.

[0006]

In order to solve the above problems, the present invention is directed to a magnetron sputtering apparatus having a planar target, which has a pair of symmetrical magnetic poles at symmetrical positions with the target sandwiched therebetween. It is characterized by the provision of a magnet unit.

[0007]

Since the magnetic poles of the two magnet units are symmetrical with respect to the target, the lines of magnetic force of the two magnet units repel each other in the vicinity of the target and become parallel to each other. Therefore, the movement of the electrons of the plasma is activated in a wide range near the target, and the plasma is proliferated. For this reason, the sputtering rate is increased as a whole, and the target is evenly consumed over a wide range.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. The magnetron sputtering apparatus according to the present embodiment includes a substrate 10 to be vapor-deposited and a flat target 1 facing the substrate 10.
1 and a pair of magnet units 12 and 15 symmetrically provided with the substrate 10 and the target 11 interposed therebetween. Each magnet unit 12, 15 has a plurality of unit magnets 13.
And a yoke 14 made of a ferromagnetic material that structurally and magnetically connects the unit magnets 13, and both magnet units 12,
The magnetic poles of the 15 unit magnets 13 are arranged so that the same poles face each other (that is, symmetrically). A plurality of substrates 10 are collectively held by a holder plate 19, and the holder plate 19 moves parallel to the target 11. This ensures the uniformity of the deposited film thickness on the substrate.

When vapor deposition is performed, the periphery of these is filled with an inert gas (usually Ar gas) having a low pressure (about 1 Pa), and the inert gas near the surface of the target 11 is turned into plasma by discharge. In addition, the substrate 10 and the target 11
A DC or AC (high frequency) voltage is applied between and.

In the magnetron sputtering apparatus of this embodiment, since the pair of magnet units 12 and 15 are symmetrically arranged with the target 11 sandwiched therebetween, as shown in FIG. The magnetic lines of force generated by 15 repel each other in the vicinity of the surface of the target 11 and become substantially parallel to the surface of the target 11 at that portion. Therefore, the movement of electrons is activated in a wide range in the plasma generated near the surface of the target 11, and the plasma generation site spreads in a wider range. This allows
The target 11 is not locally concentrated and consumed, and is uniformly consumed in a relatively wide range as shown in FIG. 1B. In addition, since the movement of electrons is activated in a wide range, more plasma is generated and the deposition rate is improved.

The center of the symmetrical arrangement of the two magnet units 12, 15 may be near the surface of the target 11, but to be exact, the surface of the plasma formed on the target surface, or a little inside thereof. Therefore, it is effective to set the portion where the plasma concentration (electron concentration) is the highest.

[0012]

As described above, in the magnetron sputtering apparatus according to the present invention, the portion where the electron motion is activated in the plasma becomes wider, so that the sputtering speed is improved. Further, the target is not locally concentrated and consumed, and is uniformly consumed in a relatively wide range. For this reason,
The efficiency of use of the target is improved, the cycle of target replacement is lengthened, maintenance of the sputtering apparatus is facilitated, and productivity of vapor deposition is improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram (a) of a magnetron sputtering apparatus which is an embodiment of the present invention and a cross-sectional view (b) showing how a target is consumed.

FIG. 2 is a configuration diagram (a) of a conventional magnetron sputtering apparatus and a cross-sectional view (b) showing how the target is consumed.

[Explanation of symbols]

10 ... Substrate 11 ... Target 12, 15 ... Magnet unit 13 ... Unit magnet 14 ... Yoke 19 ... Holder plate

Claims (1)

[Claims] 1. A magnetron sputtering apparatus having a planar target, wherein a pair of magnet units having symmetrical magnetic pole arrangements are provided at symmetrical positions with respect to the target.