TWI482871B - Sputtering target with movable cells-like magnetic controller - Google Patents

Description

Mobile cell magnetron sputtering target

The invention relates to a magnetron sputtering target, in particular to a cell magnetic control arranged behind a sputtering target, and the cell magnetic control performs collective planar motion according to a set motion track, so as to achieve uniform consumption of the sputtering target surface. A magnetron sputtering target with a uniform coating on the workpiece.

Magnetron sputtering refers to the arrangement of an electromagnet or a permanent magnet behind a sputter target in a vacuum sputtering chamber to generate a magnetic field and cause the magnetic field line to penetrate from the rear of the target to the front of the target, and then return to the target. Electromagnet or permanent magnet at the rear of the material. The plasma generator utilizes the guidance of the magnetic field to bombard the predetermined region of the metal target to knock out the metal atoms, and then deposits metal atoms on the surface of the workpiece below the target to form a thin film. The plasma gas may contain an inert gas such as argon or a reaction gas that can react with the target.

The result of this will cause the target to form an electron trap like a tunnel-like structure. This effect is further enhanced when the tunneled electron trap is further strengthened after the metal target forms a closed loop. However, it causes the plasma to form a loop, causing the target to be tunnel-like, which results in the disadvantage that the utilization of the target is significantly reduced.

U.S. Patent No. 5,399,253, issued to P.S.P. The problem of loss. The target shown in Figure 1 is 1, A magnetic strip 11 having a fixed circumference on the back side of the target is fixed to a plate 12, and the inside of the magnetic strip 11 has two magnetic strips 13 and 14 which are rotated. At the beginning of the magnetic strips 13 and 14, the polarity of the upper and lower sides of the N-S poles is exactly opposite. The rotating magnetic strips 13, 14 are perpendicular to the normal line of the target surface, one of which rotates clockwise, and the other rotates counterclockwise. The variation of the magnetic field lines penetrating through the target 1 is sequentially changed as shown in FIG. 1a -> FIG. 1b -> FIG. 1c. In Figure 1c, the magnetic strips 13 and 14 are rotated exactly 180 degrees. The position of the magnetic lines in and out of the figure will cause the surface of the target to produce a tunnel foot pole 16 similar to that of the tunnel. The target will consume faster at these locations. For large area targets, the patent discloses that more rotating magnetic strips 13 and 14 can be arranged within the fixed magnetic strip 11. as shown in picture 2.

Pius Grunenfelder, Wangs et al., U.S. Patent No. 6,454,920, entitled "Magnetron Sputtering Source", is a modified version of the magnetron sputtering source. As shown in FIG. 3, its change is that the target is cut into a plurality of blocks 1a, 1b fixed to a backing plate 5, and below the backing plate 5 is a cooling plate or cooling pipe 6. The anodes 7a, 7b are additionally provided with a strip between the target and the target. The same type of magnetic strip 11 and rotating magnetic strips 13 and 14 are also fixed.

Pius Grunenfelder, the Wangs patent does improve the uniform consumption of the target, and the sputtering area is also increased, but the ends of the target are consumed more quickly due to the constant overlap of the electron traps, making the effective area of the sputter coating and The erosion at the ends is uneven.

In view of the above, it is an object of the present invention to provide a technique to overcome the difficulties of the prior art. The target surface erosion range of the target is enlarged, and the unevenness of the target surface is effectively eliminated, and in particular, the green coating of the target side can be more uniform.

SUMMARY OF THE INVENTION One object of the present invention is to provide a magnetron sputtering design that effectively addresses the problem of conventional magnetron sputtering ends being consumed more quickly due to the constant overlap of electron traps.

Still another object of the present invention is to simplify the control of the magnetic field of the magnetron sputtering target.

Yet another object of the invention is to control coating uniformity.

Another object of the present invention is to simultaneously form a plurality of sputtering sources on a target surface to achieve high speed coating.

The invention discloses a magnetron sputtering target, comprising: a plurality of targets attached to a copper substrate, the targets are connected to a negative voltage; a driving device; a cell magnetic control device, fixed to the copper substrate, The invention comprises a substrate, a cell grid disk and a plurality of magnetic strips. And the cell grid disk and the plurality of magnetic strips are externally and internally fixed on the substrate, driven by the driving device, and at a rate within the range of the target, wherein the cell grid disk is connected The magnetic strip is formed, and the same first magnetic pole faces the targets, and the plurality of magnetic strips are distributed in the grid of the cell grid, and the outermost annular disk and the plurality of magnetics The strips face the targets with the same second magnetic pole. In addition, a separate annular disk is included on the outside of the substrate, which is fixed.

In order to make the above objects, features and advantages of the present invention more comprehensible, a preferred embodiment of a magnetron target designed in accordance with the present invention, together with the accompanying drawings, is described in detail below.

Figure 4 shows a schematic cross-sectional view of a magnetron sputtering target in the plan view of Figure 5. A cross-sectional schematic drawn by the A-A line. From top to bottom, a plurality of targets 100 are adhered to a copper base plate 110 or are fixed by screws. Below the copper base plate 110 is a cooling base plate 120. In another embodiment, the plurality of targets 100 are directly adhered to a copper cooling substrate 120. The cooling bottom plate 120 must not be a ferromagnetic material such as iron, cobalt or nickel to avoid affecting the distribution of magnetic lines of force. In addition, the cooling floor 120 needs to be surely attached to the target 100 to prevent heat dissipation. For example, lock with a screw. The target 100 is connected to a negative voltage terminal. A plurality of targets 100 are supplied with their power by a same power supply.

Below the cooling floor 120 is a cell magnetron 150. A schematic plan view of the cell magnetron 150 shown in FIG. 5, the outermost ring being an annular disk 152. The illustrated ring-shaped disk 152 is labeled as the north pole N, the inside of the ring-shaped disk 152 is the cell grid disk 155 is labeled as the south pole S, and the inner cell of the cell grid disk 155 contains a magnetic strip 158, labeled as Arctic N. In other words, either the ring disk 152, or the cell grid 155 or the other magnetic pole of the magnetic strip 158 is entering the other end of the paper (or refer to the lower end of the disk shown in Figure 4).

In one embodiment, the cell dynamic control device 150 includes three columns of mutually juxtaposed squares, and the number of squares in the middle column is one less than the number of upper and lower columns (three in the middle column, and two columns in the upper and lower columns). There are four squares juxtaposed, and are mirror-symmetric with a horizontal line passing through the center of the cell magnetron, and also mirror-symmetrical with a vertical line passing through the center of the cell magnetron 150. The juxtaposed square of the cell magnetron 150 of the present invention adds a number of designs of the small center magnetic strip 158, and the cell magnetron 150 is not fixed but moves in motion (as described below). The target consumption is more uniform without losing the effect of the electron trap between the magnetic strips.

The above cell magnetron 150 includes a cell grid 155 and the magnetic strips 158 are first fixed to a substrate 159, and the substrate 159 is further moved by another horizontal The structure 160 drives the cell magnetron 150 to present a collective motion with a predetermined planar motion trajectory. The annular disk 152 is fixed to another independent substrate 1591. The horizontal plane motion trajectory is adjusted according to the following parameters, such as target type, sputtering rate, target area, target consumption degree, and coating uniformity. The horizontal moving mechanism 160 may be a rotating shaft that includes a rotating shaft to drive a cam, or directly connects the cam, and is connected to the substrate 159 by one of a rack, a gear and a belt, a chain, and any combination. Or the motor output shaft drives a combination of three or four links. To avoid affecting the vacuum, the horizontal moving mechanism 160 and the cell magnetron 150 can be designed outside the vacuum plating chamber. Of course, if you are in a vacuum chamber, you must use a suitable shaft seal and mechanism.

The horizontal plane motion trajectory at the center of the substrate 159 may be, for example, a rectangle including a circle, an ellipse or a corner, a rounded corner, a diamond-shaped hyperelliptic trajectory, etc., and an appropriate transmission combination is selected according to the motion trajectory to achieve the predetermined motion trajectory, electronic After the trap is generated, it is changed to another place, so that the consumption of the target can be made uniform. In addition, the rate of movement of the substrate 159 can also be controlled and adjusted by the program. The moving rate is about 0.25~2cycle/s, which is about 4 cm/s~19 cm/s for a target of 300mm×300mm. The center of the planar motion trajectory does not overlap the center of the target surface in some applications to achieve a predetermined coating uniformity distribution.

The above-mentioned annular disk 152 is used to increase the sputtering rate of the surrounding target and the uniformity of the coating. The cell grid disk 155 disk 155 cell size is about 5mm × 5mm ~ 300mm × 300mm.

Further, depending on whether the target 100 is rectangular, circular or polygonal, the cell grid disk 155 is not limited to the square cell shape shown in FIG. 5, but may be further changed into a complex triangular lattice composition (as shown in FIG. 6A). , a plurality of honeycomb lattices (as shown in Figure 6B), Or a multi-layer concentric circle (as shown in Figure 6C), a multi-layered concentric petal (as shown in Figure 6D) or a multi-layer concentric heart (not shown), a square cell lattice, a complex triangular lattice, and a plurality of honeycombs The lattice shape is suitable for a square target or a circular target, and the multi-layer concentric circle, the multi-layer concentric petals, and the multi-layer concentric heart shape are suitable for a circular or nearly circular sputtering target.

In the present invention, the cell magnetron 150 includes a ring-shaped magnetic disk 152, a cell-shaped magnetic disk 155, a plurality of magnetic strips 158, and the like with a permanent magnet as a priority. The electromagnet is second. Therefore, when the magnetic disk 152, 155 or magnetic strip in the cell magnetron 150 is a permanent magnet, the distance between the cell magnetron 150 and the target can be adjusted to achieve a predetermined magnetic field strength to achieve a pitch. Change the plating rate and uniformity.

Additionally, the entire set of cell magnetrons 150 is not limited to being in the same vacuum as the sputtering target 100. The entire set of cell magnetrons 150 can also be isolated from the atmosphere.

According to still another embodiment of the present invention, the entire set of cell magnetron 150 is on an inclined surface with a bevel angle of between about 5 and 30 degrees, thereby controlling the distribution of the coating thickness.

The invention has the following advantages:

(1) The cell grid magnetic control device 150 is simple in composition, and because of the collective motion (the cell grid magnetic control device 150 is fixed on the substrate, the substrate movement trajectory is the movement trajectory of the cell grid magnetic control device 150), so only one set of driving devices is needed. Just fine.

(2) The collective motion trajectory of the cell magnetic control device 150 can be adjusted according to the above parameters, which can effectively remove the problem of uneven consumption of the target surface, in particular, the frequency of the surface arc spark (arc) of the target during sputtering is significantly reduced. In addition, the problem of low target edge utilization can be effectively solved.

(3) After the cell dynamic control device 150 causes the electron trap to be generated by collective motion, it is changed again. Location. The way to change position is more flexible than the prior art, and it is not excessively concentrated, so the target consumption is more uniform.

(4) The target material, the copper base plate and the cell grid disk are separated and designed, and the cell grid disk can be in the atmosphere. Therefore, it is easy to adjust or replace the cell grid disk, and the target material is replaced without being tied to each other.

The present invention has been described above by way of a preferred example, and it is not intended to limit the spirit of the invention. Modifications made without departing from the spirit and scope of the invention are intended to be included within the scope of the following claims. For example, a square lattice cell magnet of a cell magnetic control device may not include a ring disk in another embodiment. In other words, the ring disk is an optional component. In addition, although the sputtering target is exemplified by a plurality of separate targets, the cell magnetic control device of the present invention has the effect of balancing the target consumption, and therefore, can be applied to a single target corresponding to a cell magnetic control device. material.

11‧‧‧Fixed magnetic strip

13, 14‧‧‧Rotating magnetic strip

1, 1a, 1b‧‧‧ targets

16‧‧‧Through the foot

7a, 7b‧‧‧ flaky anode

5‧‧‧ Backplane

6‧‧‧Cooling plate or cooling line

12‧‧‧ plates

110‧‧‧ copper base plate

150‧‧‧cell magnetic control device

152‧‧‧ ring disk

155‧‧‧ cell grid disk

158‧‧‧Independent magnetic strip

160‧‧‧Horizontal moving mechanism

159‧‧‧Substrate

120‧‧‧Slow floor

1591‧‧‧Fixed disk fixed substrate

Figure 1 shows a schematic cross-sectional view of a conventional magnetron sputtering target.

1a to 1c are diagrams showing sequential changes in magnetic lines of force of the conventional magnetron sputtering target shown in Fig. 1.

2 shows a schematic cross-sectional view of a conventional magnetron sputtering target according to FIG. 1 with more in-situ rotating magnetic strips when a large-area sputtering target is used.

Figure 3 shows yet another conventional magnetron sputtering target.

Figure 4 is a cross-sectional view showing the magnetron sputtering target of the present invention taken along line A-A of the plan view of Figure 5.

Figure 5 is a plan view showing the cell magnetron of the magnetron sputtering target of the present invention.

6A to 6D are plan views showing four variations of the cell magnetron of the magnetron sputtering target of the present invention.

152‧‧‧ ring disk

150‧‧‧cell magnetic control device

158‧‧‧Independent magnetic strip

155‧‧‧ cell grid disk

Claims (10)

A magnetron sputtering target comprises at least: a target attached to a copper substrate, the target is connected to a negative voltage; a driving device; a substrate is located behind the copper substrate; and a cell magnetron is fixed to the substrate The substrate, the cell magnetic control device comprises a cell grid disk, wherein the cell grid disk is connected by a plurality of first magnetic strips to form a plurality of lattices, and a plurality of second magnetic strips located at the center of the lattices Composition, the plurality of lattices are adjacent to each other in a two-dimensional manner, and the substrate is driven by the driving device to perform a predetermined two-dimensional planar trajectory movement at a predetermined rate, the center of the planar trajectory not being opposite to the target surface The centers overlap, and the magnetic strips of the first magnetic strip and the second magnetic strip facing the target are opposite. The magnetron sputtering target according to claim 1, wherein the plurality of lattices are selected from the group consisting of squares of different sizes, equal-sized squares, honeycomb lattices, triangular lattices, and multi-layer concentric circles. One of a group of shaped, multi-layered concentric types. The magnetron sputtering target according to claim 1, wherein the cell magnetron device further comprises a ring-shaped magnetic disk, and the second substrate is fixed around the cell grid disk at a predetermined distance. The magnetic pole of the annular disk facing one side of the target is opposite to the magnetic pole of the first magnetic strip. The magnetron sputtering target according to claim 1, further comprising a spacing adjustment mechanism for adjusting the distance between the target and the cell magnetron device, thereby changing the plating rate and uniformity. The magnetron sputtering target according to claim 1, further comprising an angle adjusting mechanism for adjusting an angle between the target and the cell magnetron device, thereby changing the plating rate and the uniformity. The magnetron sputtering target of claim 1, wherein the driving device comprises a motor driving a linkage device comprising a linkage of a connecting rod or a cam or a gear, a rack or a belt or a chain. The magnetron sputtering target of claim 1, wherein the copper substrate and the cell magnetron further comprise a cooling device. The magnetron sputtering target according to claim 1, wherein the planar motion track of the center of the substrate comprises one of a circular, elliptical, rectangular or diamond-shaped hyperelliptical trajectory with a rounded corner, and the predetermined The rate is about 4-19 cm/s. A magnetron sputtering target comprises at least: a target attached to a copper substrate, the target is connected to a negative voltage; a driving device; a substrate is located behind the copper substrate; and a cell magnetron is fixed to the substrate The substrate, the cell magnetic control device comprises a cell grid disk, wherein the cell grid disk is connected by a plurality of first magnetic strips to form a plurality of lattices, and a plurality of second magnetic strips located at the center of each of the lattice strips The plurality of grids are adjacent to each other in a two-dimensional manner, and the substrate is driven by the driving device to perform a predetermined two-dimensional plane trajectory movement at a predetermined rate, the plane trajectory a center, not overlapping the center of the surface of the target, the first magnetic strip and the second magnetic strip facing opposite sides of the target magnetic pole; an annular magnetic disk fixed around the cell grid disk at a predetermined distance a second substrate, the magnetic pole of the annular disk facing one side of the target is opposite to the magnetic pole of the first magnetic strip, and the second substrate is fixed. The magnetron sputtering target according to claim 9, wherein the plurality of grids are arranged in three columns, and each column has a plurality of lattices, and the number of lattices in the middle column is relatively small, and the cells are passed through the cell. The horizontal line of the magnetic control device is mirror-symmetrical.