JPS6112866A - Plasma concentration type high-speed sputtering device - Google Patents

Abstract

PURPOSE:To provide a titled device with which a deposited film having uniform and good quality is obtaineable at a high speed and a target consisting of a magnetic material is usable by the constitution consisting in bending the plasma flow radiated from a target source and concentrating the same onto a target by means of magnets in a vacuum vessel. CONSTITUTION:Gas such as Ar which is an ion source is introduced through a gas introducing port 12 from an arrow X direction to form plasma 23 between an annular plasma source 17 consisting of a discharge cathode 13 and intermediate electrodes 14, 15 and an anode 19. The plasma flow is conducted horizontally to the inside of the vacuum vessel 11 by the cusp magnetic field generated by two sets of annular magnets 16, 18 in which equiv. current flows respectively in opposite directions. The plasma flow is then bent approximately 90 deg. and is converged uniformly to the surface of the target 20 by the powerful magnet 21 disposed below the horizontally held target 20. The sputtering of the target 20 which is maintained at the negative potential with respect to the anode 19 is thus executed and the deposited film having the high quality is obtd. at a high speed on a sample 22 disposed to face the target 20.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a plasma-intensive high-speed sputtering apparatus for depositing films in semiconductor process technology 8 surface treatment technology and the like.

Conventional Structures and Their Problems In recent years, as semiconductor processes have become faster, there has been a need for high-speed sputtering equipment that can form high-quality thin films at higher speeds.

A conventional high-speed sputtering apparatus will be explained below.

Figure 1 is a configuration diagram of a conventional high-speed sputtering apparatus, in which 1 is a vacuum chamber, 2 is a target provided in the vacuum chamber 1, 3 is a magnetic field parallel to the target 2, and 4 is a permanent magnet that generates the magnetic field 3. , 5 is a substrate facing the target 2, 6 is an electric field perpendicular to the magnetic field 3, 7 is a power source for generating the electric field 6,
8 is an introduced gas for generating plasma, 9 is a substrate 5
10 is a yoke that constitutes the magnetic circuit of the permanent magnet 4.

The operation of the high-speed sputtering apparatus configured as described above will be described below.

Magnetic field 3 parallel to the target 2 surface near the target 2 surface
is obtained by the permanent magnet 4. An electric field 6 orthogonal to the magnetic field 3 is obtained between the target 2 and the substrate 6 by a power source 7 .

The orthogonal magnetic field 3 and electric field trap electrons in the discharge region with space charges, causing magnetron discharge from the introduced gas 8. By increasing the plasma density in the vicinity of the target 2 using the permanent magnet 4, it is possible to enhance the sintering effect and perform film deposition at high speed.

However, in the above-mentioned conventional configuration, the magnetic field 3 was weak and non-uniform because the magnet configuration utilized an unnatural magnetic gear that uses a leakage magnetic field. Therefore, the film deposition rate was not satisfactory, only a portion of the target 2 was extremely exhausted, and the uniformity of the film deposition was not sufficient. Another problem is that a magnetic material cannot be used as the target 2 due to magnetic recirculation.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and aims to provide a plasma-intensive high-speed sputtering device that can deposit a uniform film at high speed and can also use a magnetic material as a target. purpose.

Structure of the Invention The apparatus of the present invention includes a vacuum chamber, a plasma source installed in the vacuum chamber, a target placed in the vacuum chamber, and a plasma flow for concentrating the plasma emitted from the plasma source on the target. This is a plasma-concentrating high-speed sputtering device equipped with a magnetic field to bend the target by 90 degrees and a sample placed opposite the target. It is possible to obtain film deposition, and by separating the permanent magnet and target, a magnetic material can also be used for the target.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

[Embodiment 1] FIG. 2 shows the configuration of a plasma concentration type high speed sputtering apparatus in a first embodiment of the present invention. In FIG. 2, 11 is a vacuum chamber, 12 is a gas inlet, 13 is a discharge cathode, 14 is a first intermediate electrode, 15 is a second intermediate electrode, and 16
is a permanent magnet provided in the first intermediate electrode 14, and 1γ is the discharge cathode 13, the first intermediate electrode 14, and the second intermediate electrode 1.
6, a ring-shaped plasma source, 18 a coil, 19 an anode of the plasma source 17, 20 a target, 2
1 is a bar-shaped permanent magnet placed under 20,
22 is a sample placed opposite to the target 20.

The operation of the plasma concentration high speed sputtering apparatus of the first embodiment constructed as described above will be explained below.

First, when the ring-shaped plasma source 17 introduces, for example, argon as an ionized gas in the X direction from the plurality of gas introduction ports 12, a large-area plasma is generated from the annular slit. The two intermediate electrodes 14, 15 provide a pressure difference between the cathode region and the anode region. For example, with argon gas of 0.6 Pa m”/Sec, the cathode area is approximately 40 P.
a, The anode region (near target 2o) was maintained at approximately o, 1 Pa. By the DC power supply 25, the potential difference between the cathode 13 and the first intermediate electrode 14 is, for example, 40V, the potential difference between the first intermediate electrode 14 and the second intermediate electrode 15 is, for example, 35V, and the potential difference between the first intermediate electrode 14 and the second intermediate electrode 15 is
The intermediate electrode 15 and the anode 20 have a discharge voltage of, for example, 20V. In order to ensure sufficient magnetic field strength to guide the discharge in the two intermediate electrodes 14, 15, a cusp magnetic field created by two ring-shaped permanent magnets 16 in which equivalent currents flow in opposite directions was used.

Plasma 22 radiated horizontally from plasma source 17
In order to concentrate the discharge plasma flow 27 near the target area 20, it is necessary to bend the discharge plasma flow 27 by nearly 90 degrees. target 20
is placed perpendicular to the initial plasma flow and has a strong permanent magnet 21 (for example, a rare earth magnet of 5mCo5) inside. The surface of the magnet 20 and the surface of the permanent magnet 21 are separated by about 2 cm, so that they can be sufficiently cooled with water. FIG. 5 shows the distance dependence of the magnetic flux density in the case of the cylindrical permanent magnet 21 of φ30u×15ruL.

In FIG. 4, the X-axis is taken along the initial plasma flow 27 (along the axis of the plasma source 17) and the target 200
The y-axis is taken from the center perpendicular to the surface.

A magnetic field is required to change the direction of the discharge plasma 2-3. Since the electron flow in the discharge plasma 23 has low energy and its motion is not thermalized (not unidirectional), a method of bending it along magnetic lines of force using a horizontal magnetic field Bx and a vertical magnetic field By was used. This method is suitable for concentrating discharge power because it bends the plasma flow 27 while converging along the lines of magnetic force. BI + B, externally from the structure of the device! /
Since it is difficult to generate a strong electron flow, there is an upper limit to the energy of the horizontally emitted electron flow in the plasma. The magnetic field at the point where the plasma flow 27 is bent is By(gfLus
8) +When the plasma flow 27 is cylindrical, the average radius is a (Cm), and the energy of the electron flow in the plasma is We.
(eV), then 3.4J9a〉□・・・・・・・・・・・・・・・(1)y. Equation (1) means that the cyclotron radius of the electrons in the plasma 23 must be smaller than the radius of the plasma flow.

The unidirectional magnetic field BJc is obtained by a cusp magnetic field created by two coils 18 through which current flows in opposite directions. Fig. 6 Magnetic field 27 created by ai coil 18
showed that. FIG. 6 is a schematic diagram showing the direction of current flowing through the coil. The central magnetic field in the y direction due to the coil 18 is zero, and the magnetic field By in the y direction is almost independently determined by the permanent magnet 21 within the target 20.

In order to obtain a uniform sputtering effect at high speed, the relationship between Bx and By, the way the plasma flow 27 curves, and the way it converges on the surface of the target 20 are influenced. For example, 600 gauss on the surface of the target, x axis and y
At the intersection of the axes, it was made to be less than 1 gaugs.

The magnetic field arrangement inside the plasma source 17 can be made into the magnetic field 28 shown in FIG. 6 or the magnetic field 29 shown in FIG. 7 by the ring-shaped permanent magnet 16 and the coil 18. With the magnetic field configuration shown in FIG. 6, the magnetic field in the plasma diffusion region near the second intermediate electrode 15 can be rapidly reduced.

Therefore, a wide plasma flow 27 can be obtained.

In addition, in the magnetic field configuration shown in FIG. 7, the magnetic field 29 in the plasma diffusion region gradually decreases, so the converged plasma flow 29
You can get 7. At this time, by keeping the target layer 20 at a negative potential with respect to the anode 19, sputtering occurs.

As described above, according to this embodiment, by concentrating the plasma flow 27 directly above the curved target blade 20, the plasma density on the surface of the target 20 can be increased and the film deposition rate can be increased. Furthermore, by making the relationship between the magnetic field density and By appropriate, the uniformity of plasma on the surface of the target 20 can be improved, and the uniformity of film deposition can be improved.

[Embodiment 2] Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 8 shows a plasma source of a plasma concentrated high speed sputtering apparatus in a second embodiment of the present invention. 8th
In the figure, 3o is a vacuum chamber, 31 is a gas inlet, 32 is a discharge cathode, 33 is a first intermediate electrode, 34 is a second intermediate electrode, and 35 is a permanent magnet provided in the first intermediate electrode 33. , 36 is an insulating insulator, and 37 is a coil. The difference from the plasma source 17 in FIG. 2 is that the position of the permanent magnet 35 is offset from the center of the plasma source.

The operation of the plasma source of the plasma concentrated high speed sputtering apparatus configured as described above will be described below.

The centers of the two permanent magnets 36 are placed above the center of the first intermediate electrode 33. When the magnetic field at the center of the first intermediate electrode 33 is set to, for example, 20 gauss K, the cyclotron radius of electrons in the plasma emitted from the discharge cathode 32 becomes smaller due to the influence of the magnetic field9, increasing the plasma density. Furthermore, annihilation of ions on the surface of the first intermediate electrode is also reduced.

As described above, according to this embodiment, by shifting the center of the permanent magnet 35, the plasma density can be increased.
The film deposition rate can be further increased.

[Embodiment 3] Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.

FIG. 9 shows the configuration of a plasma concentrated high speed sputtering apparatus in a third embodiment of the present invention. In FIG. 9, 38 is a vacuum chamber, 39 is a gas inlet, 40 is a discharge cathode, 41 is a first intermediate electrode, 42 is a second intermediate electrode, 43
44 is a permanent magnet provided in the first intermediate electrode 41, the discharge cathode 40, the first intermediate electrode 41, and the second intermediate electrode 4.
2, 46 is a coil, 46 is a target, 47 is a cylindrical anode of the plasma source 44 placed so as to surround the target 46, and 48 is a plurality of cylindrical anodes arranged on the surface of 47. A permanent magnet 49 is a sample placed opposite the target 46. What is different from the plasma concentrated high speed sputtering device shown in Figure 2 is the target 46.
This is the difference between the permanent magnet 48 and the permanent magnet 48.

The operation of the plasma concentrated high speed sputtering apparatus of the third embodiment configured as described above will be explained below.

First, the plasma 50 emitted horizontally from the plasma source 44 is bent toward the target 46 by the cusp magnetic field created by the coil 46 . As shown in Figure 1o, the cusp magnetic field is created by changing the current flowing through the two coils 45 (for example, 5 A in the upper coil and 3 A in the lower coil), thereby lowering the position where the magnetic field 53 becomes zero. It can be shifted. Due to this magnetic field 63,
The plasma 5o is also bent downward.

In order to concentrate the downwardly bent plasma 5o directly above the target 46, it is necessary to confine the plasma 50 near the target 46. As shown in Figure 11,
A plurality of permanent magnets 48 are arranged at equal intervals so that the N or S poles adjacent to the outside of the non-magnetic cylindrical anode 47 are different from each other. Cusp magnetic field 54 near the surface of target 46
is generated, the electrons are reflected by the wall of the cylindrical anode 47, and the plasma 60 is confined. At this time, by keeping the target 46 at a negative potential with respect to the anode cylinder 47, sputtering occurs.

As described above, according to this embodiment, the plasma 50 can be concentrated directly above the target 46 by the cusp magnetic field 53 by the coil 45 and the cusp magnetic field 54 by the permanent magnet 48, and the target 46 and the permanent magnet 48 can be separated from each other. By doing so, a magnetic material can be used for the target 46.

In addition, in all the examples, plasma 2 due to arc discharge
3 and 50 were used, however, plasma 23 and E50 caused by glow discharge may also be used by introducing gas into a vacuum chamber.

Effects of the Invention The present invention makes it possible to obtain uniform film deposition at high speed by concentrating high-density plasma directly above the target.Furthermore, by separating the permanent magnet and the target, it is possible to deposit a magnetic material on the target. This makes it possible to realize an excellent plasma-intensive high-speed sputtering device that can be used effectively.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional high-speed sputtering apparatus, and FIG. 2 is a diagram of a plasma concentrated high-speed sputtering apparatus according to a first embodiment of the present invention.
Fig. 3 is a perspective view of the device, Fig. 4 is a schematic diagram showing the flow of plasma flow, Fig. 5 is a characteristic curve diagram of the permanent magnet, Fig. 6 a, b, and Fig. 7 a. , b is a schematic diagram showing a magnetic field, FIG. 8 is a cross-sectional view of a plasma source of a plasma concentration type high-speed sputtering apparatus in a second embodiment of the present invention, and FIG. 9 is a diagram showing plasma concentration in a third embodiment of the present invention. FIGS. 10a and 10b are schematic diagrams showing the magnetic field, and FIG. 11 is a front view of the target part. 17... Plasma source, 18... Coil, 20... Target, 21... Permanent magnet, 22... Sample, 24... ... Suba, Rimono, 26. Old... Exhaust port. Name of agent: Patent attorney Toshio Nakao (1st person)
Figure 2 @ Figure 3? ? Figure 4 Procedural Amendment Document February 1920 Showa 6θ / Date Showa 1999 Patent Application No. 1i/5rle 2 Name of Invention Plus Article 7 Medium-sized Sixth Thread IX' Ivy Element 1-3 Person Who Makes Amendment Related Patent Application Colonel Address 1006 Kadoma, Kadoma City, Osaka Prefecture Name
(582) Matsushita Electric Industrial Co., Ltd. Representative Yama
Toshihiko Shimo 4 Agent 571 Address Matsushita Electric Industrial Co., Ltd., 1006 Kadoma, Kadoma City, Osaka Prefecture, Japan Driveshaft 14 Copy i1 Watermelon cap ”-. 6. Contents of amendment (1) Specification amend the scope of claims of the patent as per the attached sheet. 2) In the 7th line of the 5th page of the same, ``installed in a vacuum chamber'' has been changed to ``
The magnetic field that bends the plasma 90 degrees so that the plasma is radiated into the vacuum chamber is corrected to the magnetic field that bends the plasma flow. (4) Correct "permanent magnet" in line 16 of page 6 to "magnet". (6) “Permanent magnet” in the 7th line of page 6 of the same page is “magnet”
will be corrected. 7) Correct all "Permanent magnet 16" on the 12th line of the 7th page to "Magnet 16" 0. 8) Correct "Plasma 22" on the 14th line to 16th line of the same page 7 to "Plasma 23". (9) Correct "Permanent magnet 21" in lines 18 to 19 of page 7 to "Magnet 21J." (1o) Change "Permanent magnet 21" in line 20 of page 7 to "Magnet 21J." Correct to "Magnet 21". (11) Correct "Permanent magnet 16" in the second line of page 10 to "Magnet 16". (12) Correct "Permanent magnet" in the 9th line of page 11 of the same page to "Magnet" K. (13) Correct "35 permanent magnets" in line 11 of page 11 to "35 magnets". (14) U permanent magnet 35 on page 11, line 16
Correct to "Magnet 35". (15) Correct "Permanent magnet 35" in the third line of page 12 to "Magnet 35". (16) "Permanent magnet" on page 12, line 15 of the same page is changed to "
Correct to "Magnet". (17) Page 15, line 20 [21...
Correct the permanent magnet J to "21...magnet" and set it to 1. 2. Claims (1) A vacuum chamber, a plasma source installed so that plasma is radiated into the vacuum chamber, a target placed in the vacuum chamber, and a plasma radiated from the plasma source onto the target. A high-speed plasma concentrating sputtering device equipped with a magnetic field that bends the plasma flow to concentrate it, and a sample placed opposite the target. (2) The plasma concentrated high speed sputtering apparatus according to claim 1, wherein the plasma source includes a ring-shaped cathode and two intermediate electrodes, and an anode near the target. (3) The magnetic field is obtained by a cusp magnetic field created by two coils with current flowing in opposite directions in the horizontal direction of the plasma, and in the vertical direction by a magnet placed under the target. A plasma concentrated high speed sputtering apparatus according to claim 1. (4) The plasma concentrated high-speed sputtering apparatus according to claim 2, characterized in that the intermediate electrode obtains a cusp magnetic field by two ring-shaped magnets arranged inside. (6) Cusp The plasma concentration type high-speed sputtering apparatus according to claim 4, wherein the magnetic field shifts a region of zero magnetic field from the center of the intermediate electrode. (6) A vacuum chamber, and plasma is radiated to the vacuum chamber. A cusp magnetic field consisting of a plasma source installed in the same way, a target placed in a vacuum chamber, a magnetic field to bend the plasma emitted from the plasma source, and a plurality of magnets to confine the plasma near the target surface. A plasma concentrated high-speed sputtering device characterized by having a target and a sample placed opposite each other. ('7) The magnetic field is created by changing the current values of two coils through which piezoelectric currents flow in opposite directions. 7. The plasma concentrated high speed sputtering apparatus according to claim 6, characterized in that it is obtained by an asymmetric cusp magnetic field.

Claims (7)

[Claims] (1) A vacuum chamber, a plasma source installed in the vacuum chamber, a target placed in the vacuum chamber, and a device for bending the plasma flow by 90 degrees in order to concentrate the plasma emitted from the plasma source on the target. A plasma-concentrated high-speed sputtering device equipped with a magnetic field and a target and a sample placed opposite each other. (2) The plasma concentrated high-speed sputtering apparatus according to claim 1, wherein the plasma source includes a ring-shaped cathode and two intermediate electrodes, and an anode near the target. (3) The magnetic field is obtained by a cusp magnetic field created by two coils with current flowing in opposite directions in the horizontal direction of the plasma, and in the vertical direction by a permanent magnet placed under the target. A plasma concentrated high speed sputtering apparatus according to claim 1. (4) The plasma concentrated high-speed sputtering apparatus according to claim 2, wherein the intermediate electrode obtains a cusp magnetic field by two ring-shaped permanent magnets arranged inside the intermediate electrode. (5) The plasma concentrated high-speed sputtering apparatus according to claim 4, wherein the cusp magnetic field shifts a region of zero magnetic field from the center of the intermediate electrode. (6) A vacuum chamber, a plasma source installed in the vacuum chamber, a target placed in the vacuum chamber, a magnetic field for bending the plasma emitted from the plasma source, and a magnetic field for confining the plasma near the target surface. A plasma concentrated high speed sputtering device characterized by having a cusp magnetic field made up of a plurality of permanent magnets, and a sample placed opposite to a target. (7) The magnetic field is obtained by an asymmetric cusp magnetic field created by different current values of two coils through which current flows in opposite directions.
Plasma concentrated high speed sputtering device as described in .