JPS63297556A - Sputtering device - Google Patents

Abstract

PURPOSE:To enable formation of stable oxide films, etc. and to improve the controllability of film quality by introducing gaseous Ar near a target, installing a mechanism for ionizing a reactive gas such as oxygen near a substrate and providing a mechanism for evacuating the part near the substrate. CONSTITUTION:After the inside of a chamber 7 is evacuated by a pump 21, the gaseous Ar and the reactive gas such as oxygen are introduced respectively through gas introducing ports 11, 13 into the chamber and further, an adequate degree of vacuum is maintained. Voltages are then impressed on the target 1 and the electrode 17 by power supplies 10 and 14 to generate discharges. The degree of vacuum is further increased and a negative voltage is impressed on a discharge drawing out electrode 18 by the power supply 10 to draw out the ions of the reactive gas such as oxygen and to guide the discharges near the substrate 9. On the other hand, a plate 19 is provided to prevent the arrival of the above-mentioned reactive gas and ions on the target 1 surface and evacuation is executed by a pump 22. Always the specified state is thereby maintained on the target 1 surface and the stable oxide film, etc., are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a sputtering apparatus for forming thin films by reactive sputtering.

2. Description of the Related Art A conventional reactive sputtering apparatus will be described below with reference to the drawings. Conventionally, a reactive sputtering apparatus has been constructed as shown in FIG.

In the figure, 34 is a cathode body that fixes a backing plate 32 to which a target 31 is metal-bonded, 34 is a plasma shield, and 36 is a target 3.
1 is a cooling water inlet of the cooling tank, and 36 is a cooling water outlet. 3A is the cathode body 33 and substrate holder 38
A chamber 39 supporting the substrate is a substrate on which a film is formed by sputtering, and is mounted on a substrate holder 38.

The operation will be explained below. 10 by opening the pulp 43 inside the chamber 37 with a vacuum pump 44.
' Evacuate to Torr level vacuum.

Thereafter, by opening the pulp 42 through the gas inlet 41, a reactive gas such as argon gas, oxygen, or nitrogen is introduced, and the pressure is set to about 2x10 Torr, and a direct current or Apply high frequency voltage.

As a result, plasma containing argon ions, reactive gas ions, and electrons is generated in the chamber 37. Since the target 31 has a negative potential, argon ions and reactive gas ions, which are positive ions, collide with the target 31.

The repelled target particles and the particles combined with the reactive gas ions form a film on the substrate holder 39 . Further, the reaction between the reaction gas and the target particles also occurs in the space between the target 31 and the substrate 39 and on the surface of the substrate 39.

Problems to be Solved by the Invention In the conventional sputtering apparatus described above, when attempting to form a thin film while introducing a reactive gas, the surface condition of the target 31 changes from moment to moment due to the reactive gas. Therefore, the sputtering rate of the target 31 changes, making it impossible to form a stable film. Therefore, when considering the increasing quantity, although the film formation speed is fast, it becomes difficult to obtain good products, and the yield becomes low.

Means to Solve the Problems In order to solve the above problems, the sputtering apparatus of the present invention installs the argon gas inlet on the chamber side near the target, ionizes the reactive gas, and directs it to the vicinity of the substrate. It was designed to be supplied.

action The effect of this technical means is as follows.

In other words, by ionizing a reactive gas and supplying it near the substrate, a reaction between the gas and sputtered particles progresses on the substrate surface, and the target surface is constantly bombarded with argon gas ions, so the surface condition remains constant. , it becomes possible to continuously form a stable film.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 shows a sputtering apparatus in one embodiment of the present invention. In Fig. 1, 3 is the cathode body that fixes the backing plate 2 on which the target 1 is metal bonded, 4 is the plasma shield, 5 is the inlet of cooling water for cooling the target 1, and 6 is the outlet of the cooling water. . T is a chamber that supports the cathode body 3 and the substrate holder 8, and 9 is a substrate on which a film is formed by sputtering, which is attached to the substrate holder 8. 1° is a power source for supplying power to the cathode body 3. 12 is a pulp for closing off the gas inlet 11.13.

Reference numeral 14 denotes a power source for applying voltage to the discharge unit 16 and the electrodes 17 installed therein. 16 is a power source for applying voltage to the discharge extraction electrode 18. 21 is a pump for evacuating the inside of the chamber 7, and 20 is its pulp. 19 is a plate for taking the differential pressure between the substrate 9 and the target 1. 22 is a differential pump, and 2o is its pulp.

The operation of the sputtering apparatus configured as described above will be explained.

The process is the same as the conventional example until high vacuum evacuation is performed.

Next, the pump 22 performs evacuation through the pulp 20. Thereafter, argon gas is introduced through the gas inlet 11, and reactive gases such as oxygen and nitrogen are introduced through the gas inlet 13. Furthermore, by pulp 2°, 2X10-2 Tor
The degree of vacuum is set to r, and a voltage is applied to the target 1 and the electrode 17 from the power supplies 1o and 14 to generate discharge. After that, set the vacuum level to 5X10' Torr,
A negative voltage is applied to the discharge extraction electrode 18 by the power supply 15, and reactive gas ions such as oxygen and nitrogen are extracted, and the discharge is guided to the vicinity of the substrate 9. Further, a plate 19 is provided to prevent reactive gases such as oxygen and nitrogen and ions from reaching the target surface, and a pump 22 is used to perform exhaustion.

As described above, according to this embodiment, only argon gas is introduced into the vicinity of the target, a mechanism for ionizing reactive gases such as oxygen and nitrogen is installed in the vicinity of the substrate 9, and a mechanism for exhausting the vicinity of the substrate 9 is provided. This makes it possible to always keep the surface of the target 1 in a constant state and form a stable oxide film, nitride film, etc.

Note that reactive gas such as oxygen and nitrogen and argon gas may be introduced from the gas inlet 13 at the same time.

Further, the substrate holder 8 may be insulated from the ground and a negative bias voltage may be applied thereto. The discharge unit 16 may use other methods such as a high frequency electrodeless discharge unit. A magnetron cathode may be used as the cathode.

Effects of the Invention As described above, the sputtering apparatus of the present invention introduces argon gas into the vicinity of the target, installs a mechanism for ionizing reactive gases such as oxygen and nitrogen near the substrate, and provides a mechanism for exhausting the vicinity of the substrate. Accordingly, a stable oxide film, nitride film, etc. can be formed. Furthermore, since stable film formation is possible, it can also be used in mass production equipment using in-line equipment. Furthermore, because the gas reaction and sputtering are separated, film quality can be better controlled and films with novel functions can be formed.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a sputtering apparatus according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional sputtering apparatus. 1... Target, 3... Cathode body, 9... Substrate, 10, 14.15...
Power supply, 11.13...Gas inlet, 16...
...Discharge unit, 17... Electrode, 18...
...Extraction electrode, 19...Plate, 7...
··Chamber. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
figure

Claims (2)

[Claims] (1) A sputtering device equipped with a cathode placed in a chamber, a gas ionization mechanism installed near the substrate on which a film is to be formed by sputtering, a gas inlet near the cathode, a plate for taking differential pressure, and a pump. . (2) The sputtering apparatus according to claim 1, wherein the substrate is insulated from ground and configured to be able to apply a negative bias voltage.