JPH0329863B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a sputtering device, and in particular to a sputtering gun that can easily and steadily attach and detach a target to a cathode and that can efficiently cool the target. The present invention relates to a sputtering device equipped with a sputtering device.

(Prior Art) Sputtering equipment is often used in the manufacture of semiconductors and other various electronic devices.

This sputtering device has a pair of electrodes arranged vertically opposite each other in a vacuum container, a target (sputter source) is attached to one electrode (cathode), and a workpiece is attached to the other electrode (anode). During installation, a negative potential is applied to the cathode using a sputter power source to generate plasma, and ion spatter or reactive ion spatter generated by this plasma is guided to the surface of the object to be treated and deposited thereon.

In this sputtering apparatus, when attaching the target to the cathode, a metal bonding method or a bolt fixing method has conventionally been used.

In the metal bonding method, as shown in FIG. 4a, the target 1 is attached to the cathode 3 using a bonding agent 2, and in the bolt fixing method, as shown in FIGS. The target 4 is fixed to the cathode 3 by forming a plurality of holes 1a at appropriate intervals and screwing bolts 4 passed through these holes into the cathode 3 side.

(Problem to be Solved by the Invention) In the metal bonding method described above, "solder" is mainly used as the bonding agent, but this solder tends to cause solder unevenness 2a as shown in FIG. 4b. Moreover, contamination due to solder diffusion to the target may occur. When the solder unevenness 2a occurs, the metal contact area with the cathode decreases, so that the temperature of the target increases during sputtering, and the holding of the target tends to become uncertain.

Incidentally, solder diffusion into the target can be prevented by pretreating the bonding surface of the target and depositing a barrier metal on it, but this has the drawback of requiring considerable time and effort.

On the other hand, the bolt fixing method is reliable and useful as a method for attaching large targets, but it requires drilling holes in expensive target material, which wastes material and processing costs. Since the bolt is exposed to plasma and evaporates, there is a disadvantage that the object to be processed is contaminated.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a sputtering apparatus which allows a target to be easily attached and detached and which can cool the target efficiently.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a vacuum container equipped with a vacuum exhaust pipe and a gas introduction pipe, and a workpiece placed in the vacuum container. A sputtering device comprising: an anode that holds an anode; a cathode disposed in the vacuum container to face the anode; and a sputtering power source that applies a voltage between the anode and the cathode to generate plasma between them. The cathode is characterized in that a gas introduction hole is formed in the cathode to introduce a cooling gas between the electrostatic chuck electrode and the target electrostatically chucked thereon.

(Function) In the sputtering apparatus of the present invention configured as described above, the target is fixed to the cathode by an electrostatic method, so there is no need to perform processing such as drilling holes on the target, and it is easy to attach and detach. Contamination of the objects to be processed is also completely prevented.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 1, a vacuum vessel 10 has a vacuum exhaust pipe 11 connected to an exhaust device (not shown) that evacuates the inside thereof, and an Ar gas or active gas controlled by a flow rate control device (not shown). A gas introduction pipe 12 that is introduced into the vacuum container 10 is connected.

An anode 14 to which a workpiece holder 13 for holding a workpiece is attached is disposed above the vacuum chamber 10 . This anode 14 is rotatably supported by a rotational drive mechanism (not shown) so that it can be evenly deposited on the object to be treated, and is maintained at a ground potential.

A cathode 15 is arranged at the lower part of the vacuum vessel 10, facing the anode 14. This cathode 15 cools the electrostatically chucked target 1 and maintains its potential at a desired negative potential, and its periphery is covered with an earth ring 17 via an insulator 16.

A sputter power supply 18 is connected to the cathode 15, and a cooling medium passage (in this example, the water channel indicated by 15a in FIG. 2) built into the cathode 15 is provided with a cooling water supply pipe 19 and a drain pipe. 20 are connected. Further, a flow rate control device 22 is connected to a gas introduction hole (15b in FIG. 2) provided at the center of the cathode 15 via a gas introduction pipe 21.

23 indicates a pressure gauge for measuring the pressure inside the vacuum container 10.

FIG. 2 shows an enlarged view of the vicinity of the cathode 15 (sputter gun) in FIG. 1. There is a magnet 3 in the conductive base plate 30 of the sputter gun.
1 is placed. This magnet 31 is connected to a magnet drive mechanism 33 via a rotating shaft 32.

An electrostatic chuck 34 is fixed to the upper surface of the cathode 15. This electrostatic chuck 34 is shown in FIGS.
As shown in the figure, the entire surface of the electrode 34a made of copper film or the like is covered with an insulating film 3 made of polyimide film or the like.
The electrode 34a is connected to a DC electrostatic chuck power supply 36 via an insulated lead wire 35.

In the sputtering apparatus of the present invention configured as described above, the workpiece is attached to the workpiece holder 13 on the anode 14 side, and the magnet drive mechanism 33
The magnet 31 is rotated about the rotating shaft 32, and a DC voltage is applied from the electrostatic chuck power supply 36 to the electrostatic chuck electrode 34a.

In this state, the inside of the vacuum container 10 is evacuated by an exhaust device (not shown) connected to the exhaust pipe 11, and then Ar gas or active gas is introduced into the tube at a flow rate controlled by a flow rate control device (not shown). 12 into the vacuum container 10, and the sputter power supply 1
8 applies a predetermined negative DC voltage or negative bias high frequency voltage to the cathode 15.

As a result, plasma 4 is placed on the upper surface of target 1.
0 is formed and target 1 is electrostatic chuck 34.
It is electrostatically chucked by the electrode 34a and fixed to the surface of the cathode 15 of the sputter gun. Further, ion spatter or reactive ion spatter is generated from the target 1, and the workpiece attached to the workpiece holder 13 is covered with the target material.

During this sputtering, the target 1 is heated by the plasma 40, but in this embodiment, cooling water is supplied to the cathode 1 through the water supply pipe 19.
The cathode 15, the electrostatic chuck, and the target 1 attached thereto are cooled.

Note that although the target 1 is firmly held in the electrostatic chuck 34 by electrostatic force, there is a slight air gap between the electrostatic chuck 34 and the target 1 due to the irregularity of their surfaces. 〓 is formed. Such air significantly increases the thermal resistance between the electrostatic chuck 34 and the target 1 and forms a host spot, but in this embodiment, the gas inlet pipe 21 and the gas Nitrogen gas and other gases are introduced into the electrostatic chuck 34 and the target 1 through the introduction hole 15b.
The formation of the hot spots is prevented.

[Effects of the Invention] As described above, according to the present invention, the target is attached to the cathode using an electrostatic chuck, which eliminates unstable attachment and wasteful material costs that would otherwise occur with the metal bonding method or bolt fixing method. This eliminates the drawbacks of high costs and processing costs, and allows the target to be easily and reliably attached to the cathode in a removable manner.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of the sputtering apparatus of the present invention, FIG. 2 is an enlarged explanatory view of the vicinity of the sputtering gun in FIG. 1, and FIGS. A cross-sectional view and a schematic diagram illustrating an electric chuck; Figures 4a and 4b are a front view and a cross-sectional view near the cathode showing the conventional metal bonding method; Figures 5a and b are illustrating the conventional bolt fixing method. FIG. 4 is a front view and a cross-sectional view of the vicinity of the cathode. 1...Target, 2...Bonding agent, 3
... cathode, 10 ... vacuum container, 11 ... exhaust pipe,
12...Introduction pipe, 13...Workpiece holder, 1
4... Anode, 15... Cathode, 15a... Cooling path,
15b...Gas introduction hole, 16...Insulator, 17...
...Earth ring, 18...Spatsuta power supply, 19...
... Water supply pipe, 20 ... Drain pipe, 21 ... Gas introduction pipe, 22 ... Flow rate control device, 23 ... Pressure gauge, 3
0... Base plate, 31... Magnet, 3
2... Rotating shaft, 33... Magnetic drive mechanism, 3
4... Electrostatic chuck, 34a... Electrode, 34b...
...Insulating film, 35...Insulated lead wire, 36...Electrostatic chuck power supply, 40...Plasma.

Claims (1)

[Claims] 1. A vacuum container equipped with an evacuation tube and a gas introduction tube, an anode placed in the vacuum container to hold the object to be processed, a cathode placed in the vacuum container facing the anode, and the In a sputtering device comprising a sputtering power source that applies a voltage between an anode and a cathode to generate plasma between them, the cathode includes an electrostatic chuck electrode and a target to be electrostatically chucked therein. A sputtering apparatus characterized in that a gas introduction hole for introducing cooling gas is formed between the sputtering apparatus.