JP2002126674A - Plasma cleaning apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To clean organic and inorganic systems by employing a single plasma cleaning apparatus. SOLUTION: An upper electrode 15 and a lower electrode 17 are arranged in a chamber 1 in which activated gas or insert gas is introduced to inside vacuum state space. A product set stage 23 is provided in the electrode 17 to place a product to be cleaned. High-frequency energy from an oscillator 35 is distributed to a first matching device 25 or a second matching device 27 by a divider 33. At this time, either one of the electrodes 15 and 17 is made to a hot electrode and the other electrode is made to a cold electrode by turning ON and OFF control switches 29 and 30 of the devices 25 and 27, i.e., when the electrode 17 loaded with the stage 23 is made into a hot electrode, the cleaning apparatus is used to clean an inorganic system. When the electrode 17 is made into a cold electrode, the cleaning apparatus is used for cleaning an organic system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a plasma cleaning apparatus.

[0002]

2. Description of the Related Art Conventionally, plasma cleaning by a plasma cleaning apparatus includes an RIE (reactive ion etching) method and a DP (direct plasma) method.

[0003] The outline of the plasma cleaning by the RIE method is as follows. After a product such as a semiconductor to be cleaned is set on the hot electrode side in a chamber in which discharge is performed by a hot electrode and a cold electrode facing each other, an argon gas or the like is used. An ion sheath is generated by introducing an active gas and generating plasma by a discharge phenomenon in the chamber, and removes dirt attached to the semiconductor by a physical sputtering action of the ion sheath. Generally, it is suitable for inorganic cleaning.

On the other hand, the outline of the DP type plasma cleaning is as follows.
After a product such as a semiconductor to be cleaned is set on the cold electrode side in a chamber where discharge is performed by the hot electrode and the cold electrode, an active gas such as O2 gas is filled, and plasma is generated by a discharge phenomenon in the chamber. This causes a chemical reaction, and the chemical reaction is used to remove dirt. Generally suitable for organic cleaning.

[0005]

The plasma cleaning apparatus is
An RIE method in which cleaning is performed by physical sputtering in response to inorganic or organic dirt;
There is a DP method in which cleaning is performed using a chemical reaction.

In the RIE method, it is necessary to set the product on the hot electrode side and to use an inert gas. In the DP system, it is necessary to set a product on the cold electrode side and to use an active gas. Therefore, a dedicated plasma cleaning device is required for each of inorganic and organic contaminants. For this reason, high equipment costs are a bottleneck.

[0007] In addition, when the inorganic dirt and the organic dirt are the same, for example, after removing the inorganic dirt, the product is once taken out, and the organic dirt is removed by another plasma cleaning device. Therefore, continuous work cannot be performed, which is not desirable in terms of workability. In addition, since the operation of once taking out the product is performed on the way, re-adhesion of the stain may occur in some cases.

Accordingly, an object of the present invention is to provide a plasma cleaning apparatus capable of removing inorganic and organic stains by using a single plasma cleaning apparatus.

[0009]

In order to achieve the above object, according to the present invention, there is provided a chamber in which an active gas or an inert gas is introduced into an inner space in a vacuum state, and a chamber disposed in the chamber and opposed to the chamber. An upper electrode and a lower electrode that fit together, a product set stage that is set on the lower electrode, and on which a product for cleaning is mounted; a first matching device that is electrically connected to the upper electrode; Second connected to
When the connection with the first matcher is ON, the second matcher
When the matching device is OFF and the connection with the second matching device is ON,
The first matching device includes a distributor having a switching contact that is turned off, and an oscillator connected to the distributor and generating a high frequency. One of the first and second matching devices is O.
In the case of N, there is a control switch that can be turned on and off, the other of which is turned off. When the upper electrode is a hot electrode and the lower electrode is a cold electrode, corresponding to ON or OFF of each control switch. When the upper electrode is a cold electrode, the lower electrode is a hot electrode.

Thus, for example, in the case of inorganic contamination, an inert gas such as an argon gas is introduced into a vacuum chamber, while a lower electrode is made a hot electrode by a distributor and a cold electrode is made an upper electrode. And As a result, the product setting stage is set on the hot electrode side, so that it can be used as an RIE type plasma cleaning apparatus for performing inorganic cleaning.

On the other hand, in the case of organic contamination, an active gas such as O 2 gas is introduced into a vacuum chamber, while a lower electrode is used as a cold electrode and an upper electrode is used as a hot electrode by a distributor. As a result, the product setting stage is set on the cold electrode side, so that it can be used as a DP-type plasma cleaning apparatus for performing organic cleaning.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be specifically described below with reference to FIGS.

In FIG. 1, reference numeral 1 denotes a chamber of a plasma cleaning apparatus. The chamber 1 is filled in the first tank 7 and the second tank 9 by the solenoid valve 5 whose internal space is maintained in a predetermined vacuum state by the vacuum pump 3 and controlled to be switched by a signal from the control unit S. It is possible to supply an inert gas such as argon or an active gas such as O2.

The chamber 1 is formed of an upper chamber section 11 and a lower chamber section 13 which can be separated vertically, and an upper electrode 15 and a lower electrode 17 which are vertically opposed to each other are arranged inside. The upper electrode 15 is fixedly supported by the upper chamber 11 via an insulator 19, and the lower electrode 17 is fixedly supported by the lower chamber section 13 via an insulator 21.

A product set stage 23 on which products such as semiconductors are mounted is provided on the upper surface of the lower electrode 17, and the upper stage 23 can be moved in and out by raising the upper chamber section 11 with respect to the lower chamber section 13. . The upper electrode 15 is electrically connected to the first matching device 25, and the lower electrode 17 is electrically connected to the second matching device 27.

First matching device 25 and second matching device 27
Has control switches 29 and 30 that can be turned on and off, and efficiently distributes high-frequency energy from an oscillator 35 distributed to one of the upper electrodes 15 by a distributor 33.
Alternatively, it has a function of sending the signal to the lower electrode 17.

The first and second matching devices 25 and 27 are controlled by the control unit S such that one of the switches is turned on by the control unit S so that the other is turned off. For example, as shown in FIG. 1, the control switch 29 which is turned on turns off the circuit to the ground G, so that the upper electrode 15 becomes a cold electrode (minus side electrode). The control switch 30 that is turned off is controlled so that the lower electrode 17 becomes a hot electrode (positive side electrode) by opening a circuit to the ground G, and corresponds to ON and OFF of the control switches 29 and 30. Then, if one of the upper electrode 15 and the lower electrode 17 becomes a hot electrode, the other is set to be a cold electrode.

The distributor 35 includes a first switch contact P1 connected to the first matching device 25, a second switch contact P2 connected to the second matching device 27, and a switching terminal connected to the oscillator 35. PL.

The switching terminal PL of the distributor 33 is connected to the first and second switch terminals P1,
P2 can be switched so as to be connected to each other. When connected to the first switch contact P1, high-frequency energy from the oscillator 35 is supplied to the first matching device 25 and when connected to the second switch contact P2, The high frequency energy from the oscillator 35 is switched and controlled by the second matching device 27, respectively.

The first and second switch contacts P1 and P2 and the control switches 29 and 3 of the first and second matching devices 25 and 27, respectively.
As shown in FIG. 5, when the switching terminal PL of the distributor 33 is on the first switch contact P1 side, the control switch 29 of the first matching device 25 is OFF and the second ON / OFF relationship of 0 is OFF. The control switch 30 of the matching device 27 is turned on.

The switching terminal PL of the distributor 33 is connected to the second
When the switch is on the switch contact P2 side, first, the control switch 29 of the matching box 25 is set to ON, and the control switch 30 of the second matching box 27 is set to OFF.

According to the plasma cleaning apparatus thus constructed, for example, as shown in FIG. 1, the switching terminal PL of the distributor 33 is connected to the second switch terminal P2, and the first matching device 2
The control switch 29 of the fifth matching device 27 is turned off and the control switch 30 of the second matching device 27 is turned off. As a result, the upper electrode 1
5 is a cold electrode, and the lower electrode 17 provided with the product set stage 23 is a cold electrode. Therefore, by introducing an inert gas such as an argon gas into the chamber 1, an RIE type plasma is used to remove inorganic dirt. It can be used as a cleaning device.

In this case, as shown in FIG.
An ion sheath is generated by generating plasma by a discharge phenomenon in the inside, and an inorganic stain attached to a semiconductor or the like is removed by a physical sputtering action of the ion sheath.

Next, as shown in FIG. 2, the switching terminal PL of the distributor 33 is set to the first switch terminal P1, the control switch 29 of the first matching device 25 is turned off, and the second controller 27 is turned off.
Control switch 30 is turned ON. As a result, since the upper electrode 15 is a hot electrode and the lower electrode 17 provided with the product set stage 23 is a cold electrode, an organic gas such as O2 gas is introduced into the chamber 1 to remove organic dirt. It can be used as a DP-type plasma cleaning apparatus.

In this case, as shown in FIG.
By generating plasma by the discharge phenomenon in the inside, O
2 Activate gas to cause chemical reaction, CO, CO2, H
It decomposes into 2O and removes organic dirt attached to semiconductors and the like.

In a series of these operations, the gas introduced into the chamber 1 corresponding to the hot electrode and the cold electrode of the lower electrode 17 provided with the product setting stage 23 is replaced with an active gas or an inert gas. The cleaning operation for removing inorganic and organic dirt can be performed continuously without taking out the product to be cleaned.

[0027]

As described above, according to the plasma cleaning apparatus of the present invention, when the upper electrode is a hot electrode, the lower electrode is a cold electrode, and when the upper electrode is a cold electrode, the lower electrode is a cold electrode. Since the hot electrode can be used, inorganic and organic cleaning can be performed by one plasma cleaning apparatus.

Therefore, inorganic and organic stains can be continuously washed without taking out the product to be washed once.

[Brief description of the drawings]

FIG. 1 is an overall block diagram showing a plasma cleaning apparatus according to the present invention.

FIG. 2 is an overall block diagram similar to FIG. 1, in which an upper electrode is a hot electrode and a lower electrode is a cold electrode.

FIG. 3 is an explanatory diagram of an operation during inorganic cleaning.

FIG. 4 is an explanatory diagram of an operation during inorganic cleaning.

FIG. 5 is an explanatory diagram showing an ON / OFF relationship between a distributor and control switches of first and second matching devices.

[Explanation of symbols]

 Reference Signs List 1 chamber 15 upper electrode 17 lower electrode 23 product set stage 25 first matching device 27 second matching device 29, 30 control switch 33 distributor 35 oscillator

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Masato Nakata, Inventor Yamato Trabotech Co., Ltd. 322, Kosai-cho, Kosai-cho, Nakakoma-gun, Yamanashi Prefecture (72) Inventor Tadashi Osawa 322 Toda Toda, Kosai-cho, Nakakoma-gun, Yamanashi Pref. 72) Inventor Eizo Higuchi 322 Toda, Kosai-cho, Nakakoma-gun, Yamanashi Pref. Yamato Lab Tech Co., Ltd. (72) Inventor Tatsuya Ishii 2-10-12 Minamisuna, Koto-ku, Tokyo Yamato Glass Co., Ltd. F-term (reference) 3B116 AA02 AA03 AB42 BC01 CD41 5F004 AA14 BA04 DA23 DA26

Claims (1)

[Claims] 1. A chamber in which an active gas or an inert gas is introduced into a vacuum internal space, an upper electrode and a lower electrode opposed to each other which are disposed in the chamber, and provided on the lower electrode for cleaning. A product set stage on which a product is mounted, a first matching device electrically connected to the upper electrode, a second matching device electrically connected to the lower electrode, and connection to the first matching device When the switch is ON, the second matching device is OFF, and when the connection with the second matching device is ON, the distributor has a switching contact that is OFF with the first matching device. An oscillator for generating high frequency,
When one of the first and second matching devices is ON,
The other switch has an ON / OFF control switch that can be turned OFF. When the upper electrode is a hot electrode and the lower electrode is a cold electrode, the upper electrode is When using a cold electrode,
A plasma cleaning apparatus wherein the lower electrode is a hot electrode.