JPS63282263A - Magnetron sputtering device - Google Patents

Abstract

PURPOSE:To obtain the title device capable of enlarging the erosion region of a target and enhancing utilization efficiency by allowing the pole of an annular magnet to rotate around the center axis of the target on the rear of the target intermediate to the center of the target and the outer periphery. CONSTITUTION:The annular magnet 10 is rotated around the center axis of the target 5 on the counter target side of cathod 3. As a result, the whole region leading to the rear at the end of the outside of the magnet 10 around the center of the target 5 can be covered by the line of magnetic force generated by the magnet 10 and extending from the target 5 to the magnet 10. Accordingly, the target surface in the whole region can be sputtered, and the utilization efficiency of the target 5 can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a magnetron sputtering apparatus that generates high-density plasma using an electric field and a magnetic field perpendicular to the electric field and strikes a target to obtain a high deposition rate.

[Conventional technology]

In a conventional magnetron device, as shown in FIG. 2, a cathode 3 connected to a DC power source 2 and a grounded anode 4 are disposed facing each other in a vacuum vessel 1, and a target 5 made of an adhering material is attached to the cathode 3. ．． A film-forming substrate 6 is attached to the anode 4 .

The vacuum chamber 1 of this device is evacuated from the exhaust lower, Ar gas is introduced from the gas inlet 8, and a voltage is applied between the two electrodes 3.4 to cause a discharge.The electrons ionized by the discharge are ejected from the target. It is confined by a magnetic field entering the target to generate a high-density plasma, and Ar'' 9 is made to collide with the target 5, causing particles ejected from the target to be deposited on the substrate 6.

[Problem that the invention seeks to solve]

A magnet placed behind the cathode is used to create a magnetic field that exits and enters the target.

Since the magnet has an annular shape with one pole in the center and the other pole surrounding it, the plasma is generated in the upper annular region between the two poles, so that the target 5 as shown in FIG.
The erosion region 51 is annular and the central part remains, so the target utilization efficiency remains at about 30 to 50%, which is a big problem in that frequent maintenance due to replacement of the sputtering device reduces the operating rate of the sputtering equipment. It becomes. In addition, since the erosion region of the target 5 facing the substrate 6 is limited to a portion, particles flying from the target rarely hit the substrate perpendicularly (recently, due to the miniaturization of semiconductor devices, As shown in , when the aspect ratio T r /T z of the contact hole 42 formed in the insulating film 41 on the semiconductor substrate becomes 1 or more (then, the perpendicular line 44 erected on the substrate surface in the incident direction 43 of the sputtered particles It is desirable that the incident angle θ is O in order to cover the bottom of the contact hole 42.
This is also a problem.

The purpose of the present invention is to solve the above problems, increase the target utilization efficiency by expanding the erosion area of the sputter target, and prevent the decrease in utilization efficiency due to target replacement.
Another object of the present invention is to provide a magnetron sputtering device that can improve the coverage of the bottom of a contact hole in a high aspect ratio device.

[Means for solving problems]

In order to achieve the above object, the present invention includes a target attached to the anode side of a cathode placed opposite to the anode in a vacuum container, and an annular magnet provided on the opposite side of the cathode to the target. One pole is located on the back surface between the center and outer circumference of the target, and the other pole surrounding that pole extends at least to the center of the target, and the magnet rotates around the center axis of the target. It shall be possible.

[Effect]

By rotating the annular magnet around the center axis of the target on the anti-target side of the cathode, the magnetic field lines exiting and entering the target through that magnet are directed behind the outer end of the magnet around the center of the target. The target surface in that range is sputtered. Therefore, the target utilization efficiency becomes high.

〔Example〕

FIG. 1 is a perspective plan view of a magnet attached to the back surface of a cathode in an embodiment of the present invention, seen from the target side. The magnet 10 is annular and shows the outline of a target 5 and a shadow 8i3 having the same dimensions around it. N pole 11 in the center.
38i12 on the outer periphery protrudes toward the target perpendicularly to the cathode surface. Due to this magnet, lines of magnetic force are generated radially in a region 13 indicated by dotted diagonal lines on the surface of the target 5. Electrons are trapped in this region of the target surface and sputter the target. Therefore, the magnet 10 is moved around the central axis 50 of the target 5 by the arrow 14.
When the target is rotated as shown in FIG.
It has risen to a certain extent. Using this magnetron sputtering device, the depth T I-1 of the insulating film 41 shown in FIG.
2Jlll1 width T* -1, On aspect ratio 1.2
When A143 was deposited in the contact hole 42, the film thickness ratio of M at the top surface of the insulating film was d, -0, 5tna, whereas the film thickness at the bottom of the contact hole was d, -0, 4-, and the film thickness ratio was 0.
8, and a coverage of 30% was obtained with the side film thickness ds=O, 15jIs.

〔Effect of the invention〕

According to the present invention, the annular magnet installed on the back surface of the target of a magnetron sputtering device is not fixed, but moves so that its central pole revolves around the central axis of the target at the back surface midway between the center and outer circumference of the target. By doing so, the magnetic force &11w1 region is generated over a wide area around the target center on the target surface, which improves target usage efficiency and prevents decrease in sputtering equipment operating rate due to target replacement. By increasing the number of particles perpendicular to the substrate surface, it was also possible to improve the coverage of the bottoms of high aspect ratio contact holes.

[Brief explanation of the drawing]

Fig. 1 is a perspective plan view of a magnet section in an embodiment of the present invention, Fig. 2 is a sectional view of a magnetron sputtering device, Fig. 3 is a sectional view of a target used in a conventional device, and Fig. 4 is a contact hole. FIG. 5 is a cross-sectional view of a target used in an apparatus according to an embodiment of the present invention, and FIG.
The figure is a cross-sectional view of a contact hole portion in which an M film is formed using an apparatus according to an embodiment of the present invention. 1: Vacuum vessel, 3: Cathode, 4: Anode, 5: Target,
6: Film forming substrate, 10: Magnet, 11: N pole, 12:
S pole. , to +Figure 1 Figure 2 Figure 4 Figure 5■ Figure 6

Claims (1)

[Claims] 1) A target is attached to the anode side of a cathode placed opposite to the anode in a vacuum container, and a ring-shaped magnet is provided on the opposite side of the cathode to the target, with one pole of the magnet located midway between the center and the outer periphery of the target. A magnetron sputtering apparatus characterized in that the other pole surrounding the pole extends at least to the back surface of the center of the target, and the magnet is rotatable around the center axis of the target.