JPH0826454B2 - Magnetron sputtering equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a magnetron sputtering apparatus that generates a large strong magnetic field region by a permanent magnet magnetic circuit built in a target support table to obtain a wide sputtering region. .

[Prior Art] As shown in FIG.
A target holder 5 having a target 4 and a magnetic circuit built therein and a substrate 6 on which a thin film is to be formed against the target 4 are held by a substrate holder 7 in a vacuum container 1 having a sputter gas introduction tube 2 and an exhaust device 3. Has been done.

The substrate 6 is formed by using such a magnetron sputtering device.
In order to form a thin film on the surface, the exhaust device 3
After evacuation by, a sputter gas such as argon gas is introduced through the sputter gas introduction pipe 7, and then a predetermined voltage is applied to the target 4. The sputter gas plasma generated at this time is focused on a magnetic field generated by a magnetic circuit composed of an annular magnet and a central magnet built in the target support 5 and collides with the target 4 to sputter the sputtered material on the surface thereof. To form a thin film on the substrate 6 at a high deposition rate. Also, as a magnetic circuit, an annular magnet having magnetic poles on the outer and inner sides of the magnet and magnetic bodies may be arranged on both sides of the magnetic pole to generate a magnetic field. Almost the same amount as the target side is generated on the side of the circuit where there is no target, and the magnetic field generation efficiency is very poor.

[Problems to be Solved by the Invention] In a conventional magnetron sputtering apparatus,
The magnetic field generated by the magnet built into the target support stands from the center of the target to the outside or from the outside to the inside,
The gas plasma is focused and sputtered by a component parallel to the target surface (hereinafter referred to as B _R ), so that the gas plasma gathers in the annular strong magnetic field region on the target and this region is locally sputtered. It becomes an eroded annular erosion region, and the other regions are regions which are hardly sputtered.

Here a strong magnetic field region and is that B _R with the target surface of the indicated area of 80% or more of the field strength of its maximum value.

This will be described with reference to the drawings. FIG. 8 shows an example of a magnet circuit built in the target support base 5, in which a central cylindrical magnet 9 and an annular magnet 10 surrounding the central cylindrical magnet 9 are arranged on the back yoke 8. . FIG. 9 is a graph showing the relationship between the position of this magnet circuit and B _R. A plan view of the strong magnetic field region shown here is as shown in FIG. 10, and the region is 35% of the target surface area. The above-mentioned gas plasma collects in this annular strong magnetic field region to form an annular erosion region.

Fig. 11 shows an example where each magnet is square, and Fig. 12 shows its B _R
The distribution graph of Fig. 13 is a plan view of the same ferromagnetic region,
The area is 32% of the target surface area.

The life of the target is until the depth of the annular erosion region reaches the target support or the target back plate, and the unusable target has many unused portions other than the erosion region.

Further, since the area to be sputtered is limited to the erosion area which is the strong magnetic field area, it also causes a decrease in the thin film formation rate.

Therefore, the present invention intends to provide a magnetron sputtering apparatus having a small target unused area and a high film formation rate.

[Means for Solving the Problems] The present invention provides a magnetron sputtering apparatus equipped with a target arranged in a vacuum container and a means for generating a magnetic field in the vicinity of the target surface. The magnetron sputtering apparatus comprises an annular magnet and an annular magnet having a magnetizing direction parallel to the target surface and in the central direction from the outer circumference.

In the above, the central magnet and each annular magnet may be formed in a square shape.

Such a magnetic circuit, as compared with the conventional magnetic circuit, by further disposing an annular magnet having a magnetizing direction in the central direction from the outer periphery and parallel to the target surface, the strong magnetic field region is 40% or more of the target surface area. It is a magnetic circuit.

[Operation] According to the present invention, a wide magnetic field region is generated by the magnetic circuit built in the target support, the unused region of the target is reduced, and the film formation rate is increased.

Embodiments Embodiments of the present invention will be described in detail below with reference to the drawings.

The present invention has a main feature in the structure of the magnetic circuit in the target support and has the same structure as that shown in FIG. 7 except that the description will be given only with respect to the magnetic circuit. It should be noted that the examples show representative examples, and do not limit the scope of the present invention. Of course, there are other examples within the scope of the present invention.

1 is a configuration diagram of a magnetic circuit for a round target of FIG.
The arrow in the figure indicates the magnetization direction of the magnet.

A central magnet 11 having a magnetizing direction perpendicular to the target surface is arranged at the center of the magnetic circuit, and an annular magnet 12 whose magnetizing direction is opposite to that of the central magnet 11 is arranged at the outer peripheral position thereof. A ring magnet 13 is arranged in parallel with the surface of the target and having a magnetizing direction from the outer circumference to the center so as to be passed over the ring magnet 12 and the ring magnet 12. A back yoke 8 is arranged on the lower surface of the magnetic circuit to prevent a leakage magnetic field.
The magnet used in the magnetic circuit must have a sufficiently large coercive force.

The flow of the magnetic flux will be described. The magnetic flux emitted from the inside of the annular magnet 13 enters the central magnet 11, and is guided by the magnetic flux of the central magnet 11 itself and goes upward in the sectional view of FIG. 1 together with the magnetic flux generated by the central magnet 11. These magnetic fluxes enter the magnetic poles outside the annular magnet 13, and the magnetic flux generated by the central magnet 11 passes through the back yoke 8 induced by the magnetic flux of the annular magnet 12 and enters the lower side of the central magnet. Therefore, in the configuration of the magnetic circuit of the embodiment, the magnetic flux always passes above the magnetic circuit, so that all the magnetic flux appears on the target side.

The target surface is located in 12mm above the magnetic circuit upper surface, shows a distribution and a strong magnetic field area of the B _R on the surface in FIG. 2, FIG. 3 shows a plan view of the strong magnetic field area. The strong magnetic field region in this example is 47% of the total target surface area.

Example 2 FIG. 4 is a configuration diagram of a magnetic circuit for a rectangular target,
A square central magnet 14 having a magnetization perpendicular to the target surface is arranged at the center of the magnetic circuit, and a square central magnet 14 and a square annular magnet 15 whose magnetization direction is opposite are arranged at the outer peripheral position of the square central magnet 14. A rectangular ring magnet 16 is arranged parallel to the surface of the target and having a magnetizing direction from the outer periphery to the center direction so as to pass over the central magnet 14 and the rectangular ring magnet 15. 8 is a back yoke.

FIG. 5 is a graph showing the distribution of B _R and the strong magnetic field region on the line AA ′ in FIG. 4, and FIG. 6 is a plan view of the strong magnetic field region. The strong magnetic field region in this example is 42% of the total target surface area.

[Effects of the Invention] In the magnetron sputtering apparatus of the present invention, for example, the strong magnetic field region on the surface is about 1.3 to 1.8 times as large as that of the conventional product, and the erosion region to be sputtered increases accordingly, so that the target unused portion Is reduced, utilization efficiency is improved, and a higher film formation rate is obtained. Therefore, excellent effects can be obtained when applied to the manufacture of semiconductor integrated circuits and magnetic recording media. Further, since the magnetic circuit of the present invention generates a strong magnetic field in a wide range, the configuration of the magnetic circuit itself can be applied to, for example, a magnetic circuit of magnetic levitation MRI.

[Brief description of drawings]

Configuration diagram of a magnetic circuit of the embodiment of Figure 1 the present invention, the distribution graph of Figure 2 is the same B _R, FIG. 3 is a plan view of the strong magnetic field area, the magnetic circuit of Figure 4 is another embodiment FIG. 5, FIG. 5 is a distribution graph of B _R , FIG. 6 is a plan view of the same strong magnetic field region, FIG. 7 is a conceptual diagram of a magnetron sputtering apparatus, FIG. 8 is a configuration diagram of a conventional magnetic circuit, FIG. 9 is a distribution graph of the same B _R , FIG. 10 is a plan view of the same strong magnetic field region, FIG. 11 is a configuration diagram of another conventional magnetic circuit, and FIG. 12 is a distribution graph of the same B _R. FIG. 13 is a plan view of the same strong magnetic field region. DESCRIPTION OF SYMBOLS 1 ... Vacuum container, 2 ... Sputtering gas introduction pipe 3 ... Exhaust device, 4 ... Target 5 ... Target support stand, 6 ... Substrate 7 ... Substrate holder, 8 ... Back yoke 9 ... Central cylindrical magnet, 10 ... Annular magnet 11 ... Central Magnet, 12 ... Annular magnet 13 ... Annular magnet, 14 ... Square central magnet 15 ... Square annular magnet, 16 ... Square annular magnet

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H01L 21/3205

Claims (3)

[Claims] 1. A magnetron sputtering apparatus comprising a target arranged in a vacuum container and means for generating a magnetic field in the vicinity of the target surface, wherein a magnetic circuit for generating a magnetic field has a central magnet, an annular magnet and an outer periphery in a central direction. And a magnetron sputtering apparatus comprising an annular magnet having a magnetization direction parallel to the target surface. 2. A magnetron sputtering apparatus as set forth in claim 1, wherein each magnet has a rectangular shape. 3. A magnetron sputtering apparatus according to claim 1, wherein the strong magnetic field region has a magnetic circuit having a target surface area of 40% or more.