JPH06280007A - Sputtering system - Google Patents

Abstract

PURPOSE:To provide a sputtering system capable of decreasing the stop time of the system accompanying exchanging collimaters and maintaining a high working ratio. CONSTITUTION:This system is newly provided with a cleaning chamber 9 to clean a collimater adjacent to a puttering chamber 1. In the cleaning chamber 9, a collimater 4b already cleaned and a collimater 4a with deposition of a sputtering film in the sputtering chamber 1 are alterneately exchanged without being exposed to the air. The collimaters are exchanged through a gate valve 8 between the chambers 1, 9 by using collimater holders 12, 13 equipped with free arms 12a, 13a, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus used in the manufacture of semiconductor integrated circuits, and more particularly,
The present invention relates to a sputtering device equipped with a collimator.

[0002]

2. Description of the Related Art A schematic view of a conventional sputtering apparatus with a collimator is shown in FIG. This device has a structure in which an aluminum target 26, which is a base material of a wiring material, and a semiconductor substrate 23 on which wiring is formed face each other with a certain space therebetween. The semiconductor substrate 23 is held by the substrate holder 22. The sputtering chamber 21 is evacuated by a vacuum pump 28. In the sputtering chamber 21, when the wiring film is embedded in the opening such as the contact hole of the semiconductor integrated circuit formed on the semiconductor substrate 23, the sputtered particles emitted from the aluminum target 26 enter the opening from random directions. Before the wiring film is sufficiently embedded in the opening, the "overhang" is formed on the upper portion of the opening, which makes it difficult to embed the wiring film in the opening.

Therefore, in the sputtering apparatus with a collimator, a kind of "sieve" called a collimator 24 is inserted between the aluminum target 26 and the semiconductor substrate 23 so that the directions of the sputtered particles in the opening are aligned. The semiconductor device has a collimator 24 capable of making only the sputtered particles incident in the direction perpendicular to the surface of the semiconductor substrate 23 reach the opening. The collimator 24 is held by a collimator holder 25. The wiring is formed by introducing argon gas into the sputtering chamber 21 through the gas introducing pipe 27 and applying electric power between the substrate holder 22 and the aluminum target 26 with a direct current (not shown) to generate plasma.

[0004]

However, in the conventional sputtering apparatus with a collimator, since the sputtered particles adhere to the collimator 24 as the wiring film is formed, it is necessary to periodically replace the collimator 24 with a new one. Generally, the replacement frequency of the collimator 24 is several times higher than the replacement frequency of the target 26.
Since the replacement of 1 is performed once with the sputtering chamber 21 opened to the atmosphere, there is a problem that replacement of the collimator 24 reduces the operating rate of the sputtering apparatus.

Therefore, an object of the present invention is to provide a sputtering apparatus capable of reducing the downtime of the sputtering apparatus due to the replacement of the collimator and maintaining a high operating rate.

[0006]

In order to achieve the above object, the present invention is directed to defining an electric discharge space between an anode arranged in a vacuum chamber and the anode, and facing the anode. In a sputtering apparatus, which is provided with a cathode target disposed in the anode, and a collimator which is disposed between the anode and the cathode target and has a function of selectively passing only sputtered particles vertically incident on the anode, a gate is provided in a vacuum chamber. A cleaning chamber is provided for cleaning the collimator connected through the valve.

In the above sputtering apparatus,
One set of collimators is arranged in each of the vacuum chamber and the cleaning chamber, and it is preferable to have a means for mutually exchanging the collimators between the vacuum chamber and the cleaning chamber.

[0008]

According to the present invention configured as described above, the collimator can be cleaned without exposing the sputtering chamber to the atmosphere because of the structure in which the cleaning chamber for cleaning the collimator is arranged adjacent to the sputtering chamber. Moreover, since one set of collimators is installed in both chambers, it is possible to perform wiring formation in the sputtering chamber while cleaning the collimators, and it is necessary to stop the device when changing the collimators. Since there is no such thing, a high operation rate can be maintained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a schematic diagram of a sputtering apparatus with a cleaning chamber for a collimator, which is an embodiment of the present invention.

This apparatus comprises a sputtering chamber 1 for forming wiring and a collimator cleaning chamber 9 for cleaning a collimator.
The sputtering chamber 1 and the collimator cleaning chamber 9 are arranged adjacent to each other via a gate valve 8. The sputtering chamber 1 and the collimator cleaning chamber 9 are evacuated by vacuum pumps 15 and 16, respectively.

In the sputtering chamber 1, a semiconductor substrate 3 carried from a chamber (not shown) is held by a substrate holder 2 with the film forming surface of the semiconductor substrate 3 facing downward. An aluminum target 6 which is a wiring material is arranged below the semiconductor substrate 3, and a collimator 4 a is held by a holder 5 between the semiconductor substrate 3 and the aluminum target 6. This holder 5 is fixed. Here, the size of the collimator 4a is 200 m in diameter.
m, thickness 5 mm, the distance between the collimator 4a and the semiconductor substrate 3 is 20 mm, and the distance between the collimator 4a and the aluminum target 6 is 60 mm.
The wiring is formed by introducing an argon gas into the sputtering chamber 1 through the gas introducing pipe 7 and applying a power between the substrate holder 2 and the aluminum target 6 with a DC power source (not shown) to generate plasma.

On the other hand, in the collimator cleaning chamber 9, the collimator 4 in the sputtering chamber 1 is
A collimator 4b having the same size as a is held by a collimator holder 12 connected to an extendable arm 12a. Further, in the collimator cleaning chamber 9, another retractable arm 13 similar to the collimator holder 12 for replacing the collimator is used.
A collimator holder 13 connected to a is provided. The holder 14 holding the arms 12a and 13a of the collimator holders 12 and 13 in the collimator cleaning chamber 9 is provided with means for moving the collimator holders 12 and 13 vertically and horizontally. The electrode 1 is provided below the collimator holders 12 and 13.
0 is placed. In addition, a cleaning gas introduction pipe 1
1 is connected to the collimator cleaning chamber 9. In the actual cleaning of the collimator, a mixed gas of chlorine and boron trichloride is introduced from the cleaning gas introduction pipe 11, and AC power is applied between the collimator and the electrode 10 by an AC power supply (not shown) to generate plasma. Then, reactive ion etching is performed.

When the collimator 4a in the sputtering chamber 1 and the collimator 4b in the collimator cleaning chamber 9 are exchanged, two collimators 4a and 4b are provided between the sputtering chamber 1 and the collimator cleaning chamber 9. The sputtering chamber 1 and the collimator cleaning chamber 9 are arranged so that the sputtering chamber 1 can be moved without being exposed to the atmosphere.
It is performed by opening the gate valve 8 between and. Next, the collimator holder 13 is moved up and down so as to have the same height as the holder 5 in the sputtering chamber 1. next,
The collimator holder 13 extends into the sputtering chamber 1 by using the extendable arm 13a, and collimator 4
Grab a and return to the collimator cleaning chamber 9. Next, the collimator holder 12 holding the already cleaned collimator 4b moves up and down so as to be at the same height as the holder 5 in the sputtering chamber 1. After that, the collimator holder 12 uses the retractable arm 12a to form the sputtering chamber 1
It extends inward and the holder 5 is fitted with the collimator 4b. After mounting, the collimator holder 12 returns to the collimator cleaning chamber 9. Next, the collimator holder 13 holding the collimator 4a is moved downward so that the collimator 4a can be cleaned, and
The collimator 4a is cleaned.

Here, the processing capacities of the apparatus of this embodiment and the conventional apparatus will be compared. The following assumptions are made for the comparison. The film formation time per semiconductor substrate is set to 2 minutes,
It is assumed that 2500 semiconductor substrates can be processed from one aluminum target. The frequency of replacement of the collimator is once for each processing of 500 semiconductor substrates, and the replacement time of the collimator in the conventional apparatus is 8 hours.
Further, the collimator cleaning time in the collimator cleaning chamber 9 in the apparatus of this embodiment is 120 minutes. The collimator exchange time here includes the collimator exchange work time and the re-evacuation time of the sputtering chamber.

In the conventional apparatus, the time for processing a semiconductor substrate from one aluminum target (2 [min / sheet] × 250)
0 [sheets]) and the time to replace the collimator 4 times (4 [times] x (8 x 60 [min / times])), giving a total of 6
It will be 920 minutes. On the other hand, in the apparatus of this embodiment, the cleaning of the collimator is performed in parallel with the wiring formation on the semiconductor substrate, and 120 minutes for the collimator cleaning can be ignored. That is, the aluminum target 1 according to the apparatus of this embodiment
The consumption time of one sheet is 5000 minutes in total, which is only the time (2 [minutes / sheet] × 2500 [sheets]) for processing a semiconductor substrate from one aluminum target. From these results, it can be seen that the apparatus of this embodiment has a processing speed about 1.4 times that of the conventional apparatus.

[0016]

As described above, according to the present invention,
By providing the collimator cleaning chamber, it is possible to reduce the down time of the sputtering apparatus, and thus it is possible to provide the sputtering apparatus having high processing capability.

[Brief description of drawings]

FIG. 1 is a schematic view of a sputtering apparatus with a cleaning chamber for a collimator according to an embodiment of the present invention.

FIG. 2 is a schematic view of a conventional sputtering device with a collimator.

[Explanation of Codes] 1 Sputtering chamber 2 Substrate holder 3 Semiconductor substrates 4a, 4b Collimator 5 Holder 6 Aluminum target 7 Sputtering gas introduction pipe 8 Gate valve 9 Collimator cleaning chamber 10 Electrode 11 Cleaning gas introduction pipe 12, 13 Collimator holder 12a, 13a Arm 14 Holding tool 15, 16 Vacuum pump

Claims (5)

[Claims] 1. A cathode target disposed in the vacuum chamber so as to define a discharge space between the anode disposed in the vacuum chamber and the anode, and to face the anode, the anode and the cathode. A collimator disposed between the vacuum chamber and a target, the collimator having a function of selectively passing only sputtered particles vertically incident on the anode, the collimator being connected to the vacuum chamber via a gate valve. A sputtering apparatus comprising a cleaning chamber for cleaning the above. 2. The sputtering apparatus according to claim 1, wherein the cleaning chamber comprises a vacuuming means for bringing the inside of the cleaning chamber into a vacuum state. 3. The sputtering apparatus according to claim 1, wherein one collimator is arranged in each of the vacuum chamber and the cleaning chamber, and the collimator is delivered between the vacuum chamber and the cleaning chamber. A sputtering apparatus having means for mutually performing. 4. The sputtering apparatus according to claim 3, wherein the means for delivering the collimator comprises a holder capable of holding one or a plurality of collimators in the cleaning chamber and delivering the collimator. The sputtering apparatus is characterized in that the tool further comprises a retractable arm. 5. The sputtering apparatus according to claim 1, further comprising means for performing a cleaning process of a collimator driven in the cleaning chamber in parallel with a wiring forming process in the vacuum chamber. apparatus.