JPH04293772A - Sputtering device - Google Patents

Abstract

PURPOSE:To provide the sputtering device which can expand the erosion region of a sputtering target and can uniformize a film quality distribution. CONSTITUTION:This device is constituted by disposing plural sets of electromagnets 11a, 13b, one set of which is constituted of plural pieces, into a sputtering cathode 8 and providing means for forming horizontal magnetic fields of a uniform size in nearly the entire area of the target 6 surface by controlling the magnitude and phase of the currents to be impressed to the sets of the respective electromagnets. The efficiency of using the target 6 is improved by expanding the erosion area and, therefore, the production cost is reduced.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a magnetron sputtering apparatus, and in particular, the present invention relates to a magnetron sputtering apparatus, and in particular, to improving target utilization efficiency by enlarging the erosion area in a sputtering target, and by realizing uniformity of film quality distribution deposited on a substrate. The present invention relates to a sputtering cathode that enables the formation of high-performance thin films.

0002

[Prior Art] The structure of a conventional magnetron sputtering cathode is as described in Japanese Patent Laid-Open No. 60-155672, in which permanent magnets with opposite polarities are arranged in the center and periphery of the cathode, respectively, so that the upper part of the target is By generating an orthogonal magnetic field nearby and capturing the electrons in the plasma generated by the discharge in the orthogonal magnetic field, positive ions (such as Ar+) collide efficiently with the target surface, making it possible to form a thin film at high speed. It had become.

0003

[Problem to be Solved by the Invention] Conventionally, permanent magnets were placed around the circumference of a magnet holder to achieve a magnetic field distribution in which lines of magnetic force were directed from one circumference to another. By rotating the magnet, the magnetic field strength was made uniform over the entire surface of the target, but in the conventional method, rotating the magnet created a sliding part, making maintenance complicated, and because permanent magnets were used, There was a problem in that it was difficult to set the optimum magnetic field value.

In order to solve the above-mentioned problems, the present invention provides a sputtering device with a sputtering cathode that has no sliding parts and has the ability to easily adjust the value of the magnetic field distributed on the target. The purpose of this introduction is to create thin films with good properties and provide a simple maintenance environment.

[0005]

[Means for Solving the Problems] In order to solve the above problems, the present invention arranges a plurality of sets of electromagnets in a sputtering cathode, and adjusts the current applied to each set of electromagnets. A means is provided for forming a horizontal magnetic field having a uniform magnitude over almost the entire target surface by controlling the magnitude and phase.

[0006]

[Operation] The above means can form a horizontal magnetic field over almost the entire area of the target surface using multiple sets of electromagnets arranged inside the cathode, so the erosion area of the target during sputtering becomes large and the target surface Almost the entire area is sputtered at a uniform speed. Moreover, this erosion area can be easily controlled by adjusting the waveform, phase, etc. of the current applied to the electromagnet. Therefore, according to the present invention, it is possible to improve the uniformity of the film thickness distribution deposited on the substrate placed on the anode and the utilization efficiency of the target.

[0007]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram of a sputtering apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic diagram of an electromagnet installed in a cathode of this embodiment. The sputtering apparatus of this embodiment includes a sputter chamber 1, a gas introduction pipe 2 for introducing argon gas into the sputter chamber 1, an exhaust pipe 3, a silicon wafer substrate 4, an anode 5, a target 6, and a cathode. 8, and electromagnets 11a, 11b, 12a, 12b, 1
3a, 13b and electromagnets 11a, 11b, 12a, 12
13b, 13a, and 13b. Note that 9 is a current lead wire, and 18 is a magnet holder.

When a DC or AC voltage of a certain magnitude is applied between the anode 5 and cathode 8 in the sputtering chamber 1, the argon introduced into the chamber 1 from the gas introduction pipe 2 is ionized, and the anode 5 A discharge space is formed between the cathode 8 and the cathode 8. At this time, the electromagnet installed in the cathode 8 generates horizontal lines of magnetic force over almost the entire area of the target 6 surface as indicated by the dotted line 14, so that electrons are captured near the top of the target 6 surface. Due to the presence of electrons, argon ions efficiently collide with the target 6, and target material atoms are knocked out and deposited on the substrate 4 attached to the anode 5. In addition, in order to suppress the increase in target temperature due to ion collision, the cathode 8
This cathode 8 also has a structure that allows cooling water to be supplied to and drained from holes 7a and 7b provided at the bottom.

FIGS. 2 and 3 show examples of the structure of the electromagnet installed within the cathode 8. FIG. Here, an example is shown in which each set includes two electromagnets. FIG. 2 shows electromagnets 12a, 12 arranged radially inside the cathode.
As shown in b, the two electromagnets located in the diametrical direction of the magnet holder 18 are considered as one set, and the dotted line 1
Generate lines of magnetic force as shown in 4. By applying a current as shown in FIG. 4, for example, to each set of electromagnets, a rotating magnetic field can be effectively generated above the target. To explain specifically using FIGS. 2 and 4, the electromagnet 11
A current of 19 is applied to the set of a and 11b, a current of 20 is applied to the set of 12a and 12b, and a current of 21 is applied to the set of 13a and 13b. As an example other than FIG. 2, it is also possible to consider a configuration in which the axis of the electromagnet is arranged perpendicularly to the surface of the magnet holder 18 as shown in FIG. Furthermore, regarding the current applied to the electromagnet, in addition to the current shown in FIG. 4, it is also possible to apply a half-wave rectified current as shown in FIG. 5, for example. Although the number of sets of electromagnets is three in this embodiment, it is of course possible to set the number to be more or less than that. At that time, the current control device 1 sets the phase difference of the current applied to each set of electromagnets, the current value, etc.
Just change it to 0.

0010

[Effects of the Invention] As explained above, according to the present invention, since a horizontal magnetic field can be obtained in most areas of the target surface, it is possible to increase the erosion area, thereby increasing the usage efficiency of the target and improving economic efficiency. Moreover, since there is no sliding part, the structure is simplified and the sputtering apparatus is easy to maintain.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a chamber of a sputtering apparatus that is an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an electromagnet installed in the cathode of this embodiment.

FIG. 3 is a diagram showing a modification of the electromagnet installed in the cathode of this embodiment.

FIG. 4 is a diagram of current waveforms applied to each set of electromagnets in this embodiment.

FIG. 5 is another current waveform diagram applied to each set of electromagnets in this embodiment.

[Explanation of symbols]

1 Sputter chamber 2 Gas introduction pipe 3 Exhaust pipe 4 Substrate 5 Anode 6 Targets 11a, 11b, 12a, 12b, 13a, 13b, 1
5a, 15b, 16a, 16b, 17a, 17b
Electromagnet 8 Cathode 7a, 7b Cooling water port 9 Current lead wire 10 Current control device 14 Line of magnetic force 18 Magnet holder

Claims (2)

[Claims] [Claim 1] A cathode electrode equipped with a target and an anode electrode capable of installing a circular substrate are arranged facing each other in a vacuum chamber capable of achieving a degree of vacuum that allows glow discharge, and discharge is realized between them. In this sputtering apparatus, particles constituting the target can be deposited on the circular substrate to form a desired thin film. A sputtering apparatus equipped with means for forming a magnetic field distribution that does not intersect with a surface. [Claim 2] A plurality of sets of electromagnets each consisting of a plurality of sets are arranged inside the cathode, and currents having different phases are applied to the sets of electromagnets. Claim 1 realizing a rotating magnetic field
The sputtering apparatus described.