JPH01177368A - Sputtering device - Google Patents

Abstract

PURPOSE:To make a target freely attachable to and detachable from a cathode by forming an inlet hole for the gas for cooling the space between an electrostatic chuck electrode and the target electrostatically chucked by the electrode in the cathode of the title sputtering device. CONSTITUTION:An anode 14 holding a material to be treated and a cathode 15 opposed to the anode 14 are arranged in a vacuum vessel 10 provided with an evacuation pipe 11 and a gas inlet pipe 12. A refrigerant passage 15a is contained in the cathode 15, the electrostatic chuck 34 to electrostatically chuck the target 1 is fixed on the upper surface of the cathode 15, and the target 1 is fixed on the surface of the cathode 15 by a power source 36. The hole 21 for introducing a cooling gas into the space between the chuck 34 and the target 1 is provided in the cathode 15, and gaseous nitrogen, etc., are supplied from a flow controller 22 through the gas inlet pipe 21 and the gas inlet hole 15. By this method, the target 1 can be easily and surely fitted onto the cathode 15.

Description

Detailed Description of the Invention [Purpose of the Invention (Industrial Application Field) The present invention relates to a sputtering device, and particularly to a sputtering device 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 gun.

(Prior Art) Sputtering apparatuses are frequently used in the manufacture of semiconductors and other various electronic devices.

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

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

In the metal bonding method, as shown in FIG. 4(a), the target 1 is attached to the cathode 3 using a bonding agent 2, and in the bolt fixing method, as shown in FIG. 5(a),
As shown in (b), a plurality of holes 1a are formed in the target 1 at appropriate intervals, and by screwing the bolts 4 passed through these holes toward the cathode 3 side, the target 4 is connected to the cathode 3 side. It is to be fixed to.

(Problems to be Solved by the Invention) In the metal bonding method described above, "solder" is mainly used as a bonding agent, but this solder does not cause solder unevenness 2a as shown in FIG. 4(b).
In addition, there is a risk of contamination due to solder diffusion to the target. When the solder unevenness 2a occurs, the metal contact area with the cathode decreases, so the temperature of the target increases during sputtering, and the holding of the target tends to become uncertain.

Incidentally, solder diffusion to the target can be prevented by pre-treating the bonding surface of the target and attaching a barrier metal, but this has the drawback of requiring a considerable amount of time and effort.

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

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

[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. In,
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 thereto.

(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 any processing such as drilling on the target, and it is easy to attach and detach. Also, contamination of the processed material is completely prevented.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

In FIG. 1, a vacuum vessel 10 includes a vacuum exhaust pipe 11 connected to an exhaust device (not shown) for evacuating the inside thereof;
A gas introduction pipe 12 that introduces an A gas or an active gas into the vacuum container 10 is connected to it, which is controlled by a flow rate control device (not shown).

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 ground potential.

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

A sputtering power supply 18 is connected to the cathode 15, and a cooling medium passage (in this example, a second
A water supply pipe 19 and a drain pipe 20 for cooling are connected to the water channel indicated by 15a in the figure. In addition, a gas introduction pipe 2 is provided in the gas introduction hole (15b in FIG. 2) provided at the center of the cathode 15.
A flow rate control device 22 is connected via 1.

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

Figure 2 is the shadow of Figure 1! ! This is an enlarged view of the vicinity of 1i15 (sputter gun), and a magnet 31 is disposed within the conductive base plate 30 of the sputter gun. 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 FIG. 3(a).

As shown in (b), the entire surface of the electrode 3a made of copper film or the like is covered with an insulating film 34b made of polyimide film or the like, and the electrode 34a is connected to the insulated lead wire 3a.
5 to a DC electrostatic chuck power supply 36.

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 31 is moved by the magnet drive mechanism 33.
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 chamber 10, and a predetermined negative DC voltage or negative bias high frequency voltage is applied to the cathode 15 by the sputtering power source 18.

As a result, plasma 40 is formed on the upper surface of the target 1, and the target 1 is electrostatically chucked by the electrode 34g of the electrostatic chuck 34 and fixed to the surface of the cathode 15 of the sputter gun. Further, ion sputtering or reactive ion sputtering is generated from the target 1, and the workpiece attached to the workpiece holder 13 is covered with the target material.

During this sputtering, target 1 is plasma 4
However, in the device of this embodiment, the cooling water is passed through the water supply pipe 19 to the water channel 15 provided in the cathode 15.
a, and after being cooled, is discharged from the drain pipe 20, so that the cathode 15, the electrostatic chuck, and the target 1 attached thereto are cooled.

Although the target 1 is firmly held on the electrostatic chuck 34 by electrostatic force, a small gap is formed between the electrostatic chuck 34 and the target 1 due to irregularities in their surfaces. Such a gap will significantly increase the thermal resistance between the electrostatic chuck 34 and the target 1, resulting in the formation of a hot spot.
In this embodiment, nitrogen gas and other gases are supplied from the flow rate control device 22 through the gas introduction pipe 21 and the gas introduction hole 15b between the electrostatic chuck 34 and the target 1, thereby preventing the formation of the hot spot. be done.

[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. The target can be easily and reliably attached to the cathode in a removable manner, eliminating the drawbacks of high costs and processing costs.

[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 diagram of the vicinity of the sputtering gun in FIG. 1, and FIG. 3(a). (b) is a cross-sectional view and a schematic diagram illustrating an electrostatic chuck used in the sputtering apparatus of the present invention, and FIG.
), (b) are front views and cross-sectional views near the cathode showing the conventional metal bonding method, and Figures 5 (a) and (b) are front views and cross-sectional views near the cathode showing the conventional bolt fixing method. It is. 1...Target, 2...Bonding agent, 3...
・Cathode, 10... Vacuum container, 11... Exhaust pipe, 12
...Introduction pipe, 13...Workpiece holder, 14...
・Anode, 15... Cathode, 15a... Cooling path, 15b
... Gas introduction hole, 16 ... Insulator, 17 ... Earth ring, 18 ... Sputter power supply, 19 ... Water supply pipe, 20 ... Drain pipe, 21 ... Gas introduction pipe, 22...
・Flow rate control device, 23... Pressure gauge 30... Base plate, 31... Magnet, 32... Rotating shaft, 3
3... Magnet drive mechanism, 34... Electrostatic chuck, 34a... Electrode, 34b... Insulating film, 35...
Insulated lead wire, 36... Electrostatic chuck power supply, 40...
·plasma. Applicant's agent Mr. Sato - Figure 1 Figure 2

Claims (1)

[Claims] 1. A vacuum container equipped with a vacuum exhaust pipe and a gas introduction pipe,
An anode placed in the vacuum container to hold the object to be processed; a cathode placed in the vacuum container to face the anode; and a voltage applied between the anode and the cathode to create a connection between them. In a sputtering apparatus comprising a sputtering power source for generating plasma, a gas introduction hole is provided in the cathode for introducing a cooling gas between an electrostatic chuck electrode and a target electrostatically chucked thereto. A sputtering device characterized in that: