JPH09171999A - Plasma cleaning treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a plasma cleaning treatment method in which a residual C component, a residual Al component, a residual Ti component, a residual Si component or the like can be removed effectively by a method wherein the inside of an etching treatment chamber after an etching treatment is plasma- treated with H2 O, a plasma treatment is executed with a gas which contains a chlorine component and a plasma treatment is executed additionally with oxygen gas. SOLUTION: A laminated structure film by a film on which a wiring pattern is formed, which uses an organic film and which contains A4 and by a barrier metal (TiW or TiN) is etched and treated with a mixed gas plasma of BCl3 and Cl2 , and a reaction product is stuck to the inside of an etching treatment chamber. In order to remove the reaction product, the inside of the etching treatment chamber 6 is plasma-treated with H2 O gas. Then, the inside of the etching treatment chamber 6 is plasma-treated with a gas which contains chlorine. After that, the inside of the etching treatment chamber 6 is plasma-treated additionally with O2 gas. Then, a plasma by a gas which is the same as that in an etching treatment for a next etching operation is generated, and the inside of the etching treatment chamber is replaced with an etching atmosphere.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma cleaning processing method, and more particularly to a film containing Al and TiW, TiN.
The present invention relates to a plasma cleaning processing method suitable for cleaning the inside of a processing chamber in etching a laminated structure film such as.

[0002]

2. Description of the Related Art Conventionally, as a cleaning method, for example, the 1993 Autumn 53rd Annual Meeting of the Society of Applied Physics, Proceedings of 465P "HBr RIE in si.
As described in “tu chamber cleaning”, a plasma treatment method using a mixed gas such as O 2 or SF 6 + O 2 for removing the reaction products deposited in the chamber during the etching treatment of the Si-based film is shown. It has been shown that the attached reaction products can be removed.

[0003]

The deposits of the reaction products generated during the etching process cause fogging of the emission monitor window for detecting the end point, which causes the non-uniformity of the etching performance and the generation of particles due to the deterioration of the end point detection accuracy. Has become. Therefore, the reaction product deposits are monitored,
The plasma emission intensity and the number of particles generated are measured, and a cleaning process is appropriately performed according to a certain control standard. The conventional cleaning method described above uses a layer containing Al and T
No consideration is given to cleaning in the etching of the laminated film such as iW and TiN film and cleaning in the plasma processing for each wafer, and the components of the reaction products are generated during the cleaning of the etching processing chamber in the etching of the laminated film containing Al. C component, Cl component, T
It is important to effectively remove the i component, the Si component, and the Al component, but in the plasma treatment containing oxygen and fluorine, Al is removed.
There is a problem that the components are excessively oxidized and it becomes very difficult to remove them.

An object of the present invention is to form a film containing Al and TiW,
It is an object of the present invention to provide a plasma cleaning treatment method capable of effectively removing the C component, Al component, Ti component, Si component, etc. remaining in the etching treatment chamber by etching the laminated structure film with a barrier metal such as TiN.

[0005]

Means for Solving the Problems The above-mentioned object is to eliminate reaction products deposited in an etching chamber by an etching process of a laminated structure film of a film containing Al and a barrier metal using an organic film on which a wiring pattern is formed. When removing, the step of exposing the etching treatment chamber to H2O gas plasma, the step of exposing the etching treatment chamber to a gas plasma containing a chlorine component after the step, and the step of exposing the etching treatment chamber to an oxygen gas plasma after the step This is achieved by continuously performing and.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a microwave etching apparatus which is an example of an apparatus for carrying out the present invention. A sample table 8 on which a sample is placed is provided in the etching chamber 6, and a quartz window 7 is attached to the upper part of the etching chamber 6 so as to face the sample table 8. A processing gas introducing pipe 12 for supplying a processing gas into the etching chamber 6 and an exhaust port 14 connected to a vacuum pump (not shown) for reducing the pressure inside the etching chamber 6 to a predetermined pressure are provided. Here, the etching chamber 6 and the quartz window 7 form an etching chamber. The coil 11 and the high frequency power supply 13 are not used during the plasma cleaning process. When etching is performed using this apparatus, the coil 11 is 400 to 1 in the quartz window.
Used to create a magnetic field of 500 gauss, high frequency power supply 1
3 is used to control the ion energy in the plasma incident on the sample stage 8.

With the device having the above structure, a laminated structure film of a film containing Al using an organic film on which a wiring pattern is formed and a barrier metal (for example, TiW or TiN) is formed by BC.
Etching is performed by a mixed gas plasma of 13 and Cl 2 (this is shown in step 1 of FIG. 1). As a result, reaction products adhere to the etching chamber. The attached reaction product is removed as follows. First,
H2O gas was introduced into the etching chamber 6 at a flow rate of 100 cc / min through the processing gas introduction pipe 12,
The internal pressure is maintained at 100 Pa, a microwave of 1000 W is generated by the magnetron 10, the microwave is introduced into the etching chamber 6 through the quartz window 7 by the waveguide 9, and plasma treatment is performed for 2 minutes. 1 in step 2). Next, instead of H2O gas, a gas containing chlorine, in this case, Cl2 gas was introduced at a flow rate of 150 cc / min, and the pressure in the etching chamber 6 was maintained at 100 Pa,
A microwave of 1000 W is generated by the magnetron 10 and plasma processing is performed for 3 minutes in the etching chamber 6 (this is shown in step 3 of FIG. 1). After that, O2 gas was further introduced into the etching chamber 6 at a flow rate of 200 cc / min, and plasma treatment was performed for 3 minutes at a microwave output of 1000 W in the state where the pressure inside the etching chamber 6 was maintained at 200 Pa (this is performed). (Shown in step 4 of FIG. 1). Further, after the plasma cleaning in the etching processing chamber, plasma of the same gas as in the etching processing is generated for the next etching to replace the etching atmosphere in the etching processing chamber (this is shown in step 5 of FIG. 1). ). Here, as the gas containing chlorine, Cl is used.
BCl3 gas or Cl2 gas and B instead of 2 gas
A mixed gas of Cl3 gas can be used.

As described above, according to the present embodiment, the C, Al, Ti, and Si components remaining in the etching chamber are made effective by performing the continuous plasma treatment with the H 2 O gas, the gas containing chlorine, and the O 2 gas. Can be removed.

In particular, the H2O plasma treatment is first performed to remove the reaction products remaining in the etching chamber, so that the hydrogen content in the H2O gas does not excessively oxidize the reaction products remaining in the etching chamber.
It is possible to remove carbon components and chlorine components from the etching chamber by using products such as O and HCl. Then, by performing a plasma treatment mainly containing a chlorine component, it is possible to effectively remove the Al, Ti, Si components and the like whose oxidation is suppressed. Furthermore, the organic substances attached to the etching chamber can be removed by the plasma treatment mainly containing O 2. As a result, compared with the conventional method, particularly Al, Ti, and Si components can be effectively removed without excessive oxidation.

[0010]

According to the present invention, a film containing Al and Ti
By etching the laminated structure film with W, TiN, etc., there is an effect that the C component, Al component, Ti component, and Si component remaining in the etching chamber can be effectively removed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a processing flow of an embodiment of a plasma cleaning processing method of the present invention.

FIG. 2 is a cross-sectional view showing an example of an apparatus for carrying out the plasma cleaning processing method of the present invention.

[Explanation of symbols]

6 ... Etching chamber, 7 ... Quartz window, 8 ... Sample stage, 9 ... Waveguide, 10 ... Magnetron.

Claims (4)

[Claims] 1. An etching process for removing a reaction product attached to an etching chamber by an etching process of a laminated structure film of an Al-containing film and a barrier metal using an organic film having a wiring pattern formed thereon. A step of exposing the chamber to H2O gas plasma, a step of exposing the etching chamber to a gas plasma containing a chlorine component after the step, and a step of exposing the etching chamber to an oxygen gas plasma after the step are successively performed. A method of plasma cleaning treatment characterized by performing. 2. A plasma cleaning treatment method according to claim 1, wherein the barrier metal during etching treatment is TiW or TiN. 3. The processing pressure in the etching processing chamber in the plasma cleaning according to claim 1 is 50 Pa to 3
A plasma cleaning treatment method at 00 Pa. 4. The gas containing the chlorine component according to claim 1 is Cl.
A plasma cleaning treatment method using 2 gas, BCl3 gas, or a mixed gas thereof.