JPH0681146A - Magnetron sputtering device - Google Patents

Abstract

PURPOSE:To stably form high-quality films free from contamination on a substrate by installing an electrode plate for cleaning a collimator to the magnetron type sputtering device having a collimator between a substrate to be treated and a target. CONSTITUTION:The target 3 of the magnetron type sputtering device and the substrate 7 to be formed with films are disposed to face each other and the target 3 is driven by the Ar ions generated by electric discharge to form the films of the target material on the substrate 7. The collimator 10 as a filter for extracting the components perpendicular to the substrate 7 among the evaporated atoms of the target 3 is placed on the front surface of the substrate 7, and further, a rotatable shutter 13 is disposed between the collimator and the target. The substrate 7 is removed from a holder 6 and the shutter 13 is swiveled to cover the target 3 when the hole of the collimator 10 is diminished by the adhesion of the target material by sputtering. The switch of a power source 12 is thereafter turned on to accelerate the Ar ions and to drive the surface of the collimator 10, by which the deposited metal is removed and the operation of the collimator 10 is normalized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetron type sputtering apparatus, and more particularly to a magnetron type sputtering apparatus having a filter for improving step coverage.

[0002]

2. Description of the Related Art FIGS. 3 (a) and 3 (b) are a diagram showing a configuration of a main part and a plan view of a collimator in an example of a conventional magnetron type sputtering apparatus. As shown in FIG. 3, a conventional magnetron-type sputtering apparatus has a holder 6 for holding a wafer, which is a semiconductor substrate, at ground potential.
And the target 3 arranged to face the holder 6.
A magnet pair 2 that holds the target 3 and is composed of a plurality of magnets; a sputtering power source 1 that applies a voltage to the magnet pair 2; and a ground potential collimator that is arranged between the holder 6 and the target 3. Have ten.

In the magnetron type sputtering apparatus having such a structure, the electrons emitted from the Al target 3 to which a negative voltage is applied by the sputtering power source 1 are affected by the magnetic field 5 formed by the rotating magnet pair 2. Exercise. In particular, magnetic force lines having a component parallel to the Al target 3 and the surface cause cycloid motion of electrons on the surface of the Al target 3 and thus accelerate the ionization of Ar, and the ion of Ar 8
To produce. The Ar ions 8 collide with the Al target 3 that is the cathode and knock out the Al atoms 9 of the target material,
A filter for extracting a component of the l-atom 9 that is almost vertical to the wafer 7 (hereinafter referred to as collimator 10)
Al atoms 9 reach on the wafer 7 via and the Al film is deposited.

[0004]

In this conventional magnetron type sputtering apparatus, the sputtered atoms are deposited on the collimator and are stacked on the side wall of the hole of the collimator, and the hole becomes smaller and the sputter rate gradually decreases. This not only deteriorates the reproducibility of the sputtered film thickness of the wafer, but also causes the problem that the film on which the refractory metal or the like adheres to the collimator is peeled off and dust is frequently generated and the film quality is significantly deteriorated.

It is an object of the present invention to provide a magnetron type sputtering apparatus which constantly maintains a high sputtering rate, obtains a reproducible film thickness, and does not cause contamination in the film formation.

[0006]

A magnetron type sputtering apparatus according to the present invention comprises a holder for holding a semiconductor substrate at a ground potential, a target arranged facing the holder,
In a magnetron type sputtering apparatus having a filter for extracting a vertical component of sputtered atoms emitted from this target, an electrode plate that moves relatively to the filter and covers the filter, and an electric potential is applied to the electrode plate and the filter. It has a power supply.

[0007]

The present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a structure of a main part in an embodiment of a magnetron type sputtering apparatus of the present invention. This magnetron type sputtering device, as shown in FIG.
A shutter plate 1 which is arranged between the Al target 3 and the collimator 10 and is rotatable around a rotation shaft 13a.
3, and a cleaning power source 12 for applying a voltage to the shutter plate 13 and the collimator 10 via the changeover switch 11. Otherwise, it is the same as the conventional example.

Next, the operation of this magnetron type sputtering apparatus will be described. First, the shutter plate 13 is swung to retract from the front of the target 3. And changeover switch 1
With 1 turned off, a sputtered film is formed on the wafer 7 according to the same sputtering principle as described in the conventional example. Next, when cleaning the collimator 10, after removing the wafer 7 from the holder 6, the shutter plate 13 is swung around the rotation shaft 13a to cover and close the target 3. Next, the changeover switch 11 is turned on, and the generated Ar ions are accelerated to strike the surface of the collimator 10 to remove the metal substance attached to the surface. The conditions at this time are
For example, the pressure is 10 mTorr in the Ar atmosphere, the output of the sputtering power source 1 is 1000 W, and the processing time is about 60 sec. Such cleaning may be performed every time the wafer is sputtered, or after a plurality of films are formed.

FIG. 2 is a view showing the configuration of the main part of another embodiment of the magnetron type sputtering apparatus of the present invention. As shown in FIG. 2, this magnetron type sputtering apparatus includes a collimator 14 having the same structure as the collimator 10 symmetrically with respect to the rotating shaft 15a, an electrode plate 15 arranged to face the collimator 14, and a ground potential. That is, the cleaning power source 12 for applying a potential to the electrode plate 15 is provided for the rotating shaft 15 and the collimator 14. Otherwise, it is the same as the conventional example.

Next, extending the differences from the above-described embodiment, this embodiment is provided with two collimators and the cleaning electrode 15 is provided at a place different from the place where sputtering is performed. There is.

As a result, the collimator can be cleaned at the same time as the sputtering, and by separating the sputter part and the cleaning part, generation of dust in the sputter part can be suppressed as much as possible. Further, the replacement of the collimator having the sputtered film and the cleaned collimator can be performed by rotating the rotating shaft 15a as a center. This operation has an advantage that it can be carried out while the wafer is being transported, and the other collimator can be cleaned while the other collimator is sputtering.

[0013]

As described above, according to the present invention, the electrode plate for accelerating the ion molecules of the gas to collide with the collimator is provided, and the collimator to which the metal substance adheres is cleaned at an arbitrary frequency, so that the hole of the collimator is By removing the metal film attached to the side wall of the film, there is an effect that it is possible to prevent a decrease in the sputter rate and a deterioration in film thickness reproducibility. Further, particularly in the case of a high melting point metal, it is possible to prevent the occurrence of a lot of dust due to the film deposition on the collimator becoming thick and peeling.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a main part in an embodiment of a magnetron type sputtering apparatus of the present invention.

FIG. 2 is a diagram showing a configuration of a main part in another embodiment of the magnetron type sputtering apparatus of the present invention.

FIG. 3 is a diagram showing a configuration of a main part and a plan view of a collimator in an example of a conventional magnetron type sputtering apparatus.

[Explanation of symbols]

 1 Sputtering Power Supply 2 Magnet Pair 3 Al Target 4 Erosion Region 5 Magnetic Field 6 Holder 7 Wafer 8 Ar Ion 9 Al Atom 10,14 Collimator 11 Changeover Switch 12 Cleaning Power Supply 13a, 15a Rotating Shaft 15 Electrode Plate

Claims (1)

[Claims] 1. A magnetron-type sputtering apparatus having a ground potential holder for holding a semiconductor substrate, a target arranged facing the holder, and a filter for extracting a vertical component of sputtered atoms emitted from the target. A magnetron type sputtering apparatus comprising: an electrode plate that moves relative to the filter and covers the filter; and a power supply unit that applies a potential to the electrode plate and the filter.