KR20080020722A - Plasma processing apparatus and method for treating substrates using the same - Google Patents

Abstract

A plasma processing apparatus is provided to improve uniformity of a plasma treatment process by generating a high discharge effect on the entire surface of a substrate. A plasma treatment process is performed in a process chamber(100). Upper and lower electrodes(210,220) are installed in the process chamber, confronting each other. A gas supply member supplies process gas in a manner that a flow of the process gas is induced from the lateral surface of the circumference of the substrate loaded between the upper and the lower electrodes toward the center of the substrate. An exhaust hole(222) for exhausting byproducts generated during a fabricating process can be formed in the center part of the lower electrodes.

Description

Plasma processing apparatus and substrate processing method using the same {PLASMA PROCESSING APPARATUS AND METHOD FOR TREATING SUBSTRATES USING THE SAME}

1 is a schematic configuration diagram showing an example of a plasma processing apparatus according to the present invention;

FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1.

3 is a schematic operation state diagram of a plasma processing apparatus according to the present invention.

<Description of Symbols for Main Parts of Drawings>

100: process chamber 120: side wall

210: upper electrode 220: lower electrode

222: exhaust hole 300: cooling member

500: power supply 600: support pin

710: gas inlet 760: gas flow passage

770: gas injection hole

TECHNICAL FIELD The present invention relates to a semiconductor manufacturing apparatus and method, and more particularly, to a plasma processing apparatus and method for generating a plasma in an atmospheric pressure to process a substrate.

In general, plasma refers to an ionized gas state composed of ions, electrons, radicals, and the like, and plasma is generated by a very high temperature, a strong electric field, or high frequency electromagnetic fields (RF Electromagnetic Fields).

Particularly, plasma generation by glow discharge is performed by free electrons excited by direct current or high frequency electromagnetic field, and the excited free electrons collide with gas molecules to generate active species such as ions, radicals and electrons. ) In addition, such active species physically or chemically act on the surface of the material to change the surface properties. This change in the surface properties of the material by the active species is called plasma surface treatment.

The plasma processing apparatus refers to a device for depositing a reaction material into a plasma state and depositing the same on a semiconductor substrate, or cleaning, ashing, or etching a substrate using the reaction material in a plasma state.

Such a plasma processing apparatus can be classified into a low pressure plasma processing apparatus, an atmospheric pressure plasma processing apparatus, and the like according to the pressure state in which the atmospheric pressure in the chamber in which the plasma state is formed is present.

The low pressure plasma processing apparatus is a processing apparatus that generates a glow discharge plasma under a low pressure close to vacuum to form a thin film on a substrate, or to etch or ash a predetermined material formed on the substrate. However, such a low pressure plasma processing apparatus requires expensive equipment such as a vacuum chamber and a vacuum exhaust apparatus, and also has a problem in that equipment maintenance and vacuum pumping time are lengthened because of a complicated configuration in the apparatus.

For this reason, the atmospheric pressure plasma processing apparatus which processes a board | substrate by generating a discharge plasma under atmospheric pressure which does not require the equipment of a vacuum condition has been proposed. Atmospheric pressure plasma processing apparatus, for example, a atmospheric pressure plasma processing apparatus having a dielectric barrier discharge (DBD) structure, when the electrode in the plasma processing chamber is insulated with a dielectric material having good insulating properties, and then a high frequency power is applied, Silent discharge occurs between the electrodes, and even and stable state under atmospheric pressure by using an inert gas such as helium (He) or argon (Ar) that is metastable as a carrier gas. Plasma can be obtained.

In the discharge electrode of the atmospheric pressure plasma dielectric barrier discharge (DBD) structure, the distance between the upper electrode and the lower electrode is managed at minute intervals of several hundred micrometers. However, in supplying the plasma processing gas between the finely spaced upper and lower electrodes, the supply pressure of the gas is not evenly transmitted to the space between the electrodes, so that an unbalanced gas is supplied. For this reason, in the etching or ashing process of the board | substrate using plasma, there existed a problem that the uniformity of the etching or ashing after plasma processing of a board | substrate fell.

Therefore, the present invention was created to solve the problems in view of the conventional conventional plasma processing apparatus as described above, and an object of the present invention is to uniformly supply the processing gas to the plasma processing region between the discharge electrodes. The present invention provides a plasma processing apparatus capable of improving uniformity of a plasma processing process and a substrate processing method using the same.

In order to achieve the above object, a plasma processing apparatus according to the present invention includes a process chamber in which a plasma processing process is performed; An upper electrode and a lower electrode installed to face the inside of the process chamber; And a gas supply member supplying the processing gas to guide the flow of the processing gas from the side space around the substrate loaded between the upper electrode and the lower electrode toward the center portion.

In the plasma processing apparatus of the present invention having the configuration as described above, it is preferable that an exhaust hole for exhausting a by-product generated during the process is formed in the center of the lower electrode.

According to an aspect of the present invention, the apparatus further includes a cooling member coupled to the upper portion of the upper electrode, the cooling member is formed with a cooling line circulating the cooling fluid to cool the heat generated during the plasma discharge; .

In order to achieve the above object, the substrate processing method of the present invention is a method of processing a substrate using a plasma, the substrate is loaded in the plasma processing region between the upper electrode and the lower electrode, the side space around the substrate And processing the substrate by supplying the processing gas so as to guide the flow of the processing gas toward the central portion.

In the substrate processing method according to the present invention having the configuration as described above, the method preferably exhausts the by-products generated during the plasma processing process through the exhaust hole formed in the center of the lower electrode.

According to one aspect of the invention, the method preferably circulates a cooling fluid in a cooling line of a cooling member provided on an upper surface of the upper electrode to cool the heat of the upper electrode generated during plasma discharge.

Hereinafter, a plasma processing apparatus and a method of treating a substrate using the same according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible, even if shown on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In the following embodiment, a plasma ashing apparatus for removing an unnecessary photoresist layer remaining on a substrate after a photographing process is described as an example. However, the technical spirit of the present invention is not limited thereto, and may be applied to other types of devices for depositing film quality on a substrate or cleaning or etching the substrate using plasma.

(Example)

1 is a schematic configuration diagram illustrating an example of a plasma processing apparatus according to the present invention, and FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1.

1 and 2, the plasma processing apparatus 10 according to the present exemplary embodiment has a space in which a plasma processing process is performed and includes a process chamber 100 having an open bottom. The process chamber 100 has a lower wall 110 having an opening formed therein. A side wall 120 extending upward is coupled to an edge of the lower wall 110, and an upper wall 130 is coupled to an upper end of the side wall 120 to seal an upper space in the process chamber 100.

A pair of parallel flat electrode 200 is provided inside the process chamber 100. The electrode 200 is an upper electrode 210 installed on the upper end of the process chamber 100, and a lower electrode 220 provided on an upper surface of the lower wall 110 of the process chamber 100 so as to face the upper electrode 210. It includes. The lower electrode 220 is disposed on the upper surface of the lower wall 110 of the process chamber 100 to seal the lower space in the chamber 100. Here, the interval between the upper electrode 210 and the lower electrode 220 is managed at minute intervals of several hundred micrometers. For this reason, in supplying the plasma processing gas between the upper electrode 210 and the lower electrode 220, the plasma processing gas must be supplied so that the supply pressure of the gas is uniformly transmitted to the space between the electrodes 200. . The upper electrode 210 and the lower electrode 220 may be made of a conductive metal such as stainless steel, aluminum, and copper.

The lower surface of the upper electrode 210 is provided with a dielectric film 230 having good insulating properties, the dielectric film 230 prevents damage to the upper electrode 210 due to the arc (Arc) generated during the generation of plasma. . As the material of the dielectric film 230, quartz or ceramic may be used.

The upper surface of the upper electrode 210 is provided with a cooling member 300 for cooling the heat generated in the upper electrode 210 during the plasma discharge. The cooling member 300 may be provided as a plate member having a shape corresponding to the upper electrode 210, and a cooling line 310 through which the cooling fluid circulates is formed therein.

The heat transfer member 320 may be provided between the upper electrode 210 and the cooling member 300 so that heat of the upper electrode 210 may be efficiently transferred to the cooling member 300. The heat transfer member 320 may include graphite. A plate member made of (Graphite) material may be used.

An exhaust hole 222 is formed through the center of the lower electrode 220. An exhaust line 410 is connected to the exhaust hole 222, and an exhaust member 420 such as a pump for suctioning and discharging the process byproduct in the process chamber 100 is disposed on the exhaust line 410.

In addition, the upper electrode 210 and the lower electrode 220 is connected to the power supply unit 500 for applying power. The upper electrode 210 is connected to a radio frequency (RF) power source and the lower electrode 220 is grounded. The power supply unit 500 applies high frequency power to the upper electrode 210 to emit electrons for generating plasma from the upper electrode 210. It is preferable to use a frequency band of a high frequency (RF) power supply for plasma generation from 50 Hz to 2,45 GHz.

The substrate W to be processed is loaded into the plasma processing region S between the upper electrode 210 and the lower electrode 220. The loaded substrate W is supported by the support pins 600 disposed on the upper surface of the lower electrode 220. The support pins 600 are provided to protrude upward from the lower electrode 220, and are disposed in a predetermined arrangement on the upper edge portion of the lower electrode 220.

As described above, since the interval between the upper electrode 210 and the lower electrode 220 is managed at minute intervals of several hundred micrometers, the plasma processing gas is supplied between the upper electrode 210 and the lower electrode 220. In supplying, the plasma processing gas must be supplied so that the supply pressure of the gas is uniformly transmitted to the space between the electrodes 200.

To this end, the present invention supplies the processing gas to the plasma processing region (S) through the side space between the upper electrode 210 and the lower electrode 220, the exhaust hole 222 formed in the center of the lower electrode 220 It has a configuration to exhaust the by-products generated during the process through.

As shown in FIG. 1, a gas inlet 710 for injecting a processing gas is formed in a sidewall of the process chamber 100. The gas inlet 710 may be formed at an intermediate point height between the upper electrode 210 and the lower electrode 220 to supply a processing gas to a side surface between the upper electrode 210 and the lower electrode 220. The gas inlet 710 is connected to a gas supply line 720 that provides a supply path for processing gas. The gas supply source 730 is connected to the other side of the gas supply line 720 connected to the gas inlet 710. On the gas supply line 720 between the gas inlet 710 and the gas source 730, a filter 740 for filtering the process gas supplied from the gas source 730 and a valve 750 for adjusting the supply flow rate of the process gas. Are arranged respectively.

Inside the sidewall of the process chamber 100, as shown in FIG. 2, a gas flow passage 760 is formed to provide a passage through which the process gas provided through the gas inlet 710 moves along the sidewall 120. . In addition, a plurality of gas injection holes 770 are formed in the inner sidewall of the process chamber 100 to be connected to the gas flow passage 760. The gas injection holes 770 may be formed at a position on the sidewall 120 corresponding to the height between the upper electrode 210 and the lower electrode 220.

The gas injection holes 770 spray the processing gas provided through the gas inlet 710 and the gas flow passage 760 into the side space of the plasma processing region S between the upper electrode 210 and the lower electrode 220. do. Then, the processing gas supplied to the side space of the plasma processing region S is guided toward the center of the plasma processing region S. As shown in FIG. In this way, the flow of the processing gas is guided from the side space of the plasma processing region S toward the center portion, whereby the gas supply pressure in the plasma processing region S can be made uniform.

As described above, the plasma is generated using the process gas in which the flow is induced, and the substrate W is processed by the generated plasma. In addition, the untreated gas and by-products generated during the process are discharged through the exhaust hole 222 formed in the center of the lower electrode 220.

As described above, the supply pressure of the processing gas is uniformly transmitted to the plasma processing region S between the upper electrode 210 and the lower electrode 220 so that the flow of the processing gas is uniform to the plasma processing region S. In this way, it is possible to generate a higher discharge effect on the entire surface of the substrate to improve the uniformity of the plasma treatment process.

3 is a schematic operation state diagram for explaining a process of processing a substrate using the plasma processing apparatus according to the present invention.

Referring to FIG. 3, the substrate W is first loaded between the upper electrode 210 and the lower electrode 220. The loaded substrate W is supported by the support pins 600 disposed on the upper surface of the lower electrode 220.

Thereafter, the plasma processing gas is supplied through the gas inlet 710 formed in the outer sidewall 120 of the process chamber 100. The process gas supplied through the gas inlet 710 is supplied to the gas injection holes 770 connected to the gas moving path 760 via the gas moving path 760 inside the sidewall 120, and the gas injection hole The 770 spray the processing gas into the side space of the plasma processing region S. The processing gas introduced into the side space of the plasma processing region S flows along the upper electrode 210 and the lower electrode 220 and is guided toward the center of the plasma processing region S.

After the processing gas is supplied to the plasma processing region S, a high frequency power of a predetermined frequency is applied from the power supply unit 500 to the electrodes 200, and a strong high frequency electric field is formed between the electrodes 200. The processing gas is turned into a plasma state by the high frequency electric field.

The plasma generated in this way is applied to the substrate W to remove the unnecessary photoresist layer remaining on the substrate W. During the ashing process of removing the photoresist layer, process by-products are generated in the plasma treatment region S, and the process by-products are processed through the exhaust hole 222 formed in the center of the lower electrode 220. Is discharged to the outside.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, the processing gas can be uniformly supplied to the plasma processing region between the discharge electrodes.

In addition, a higher discharge effect is generated on the entire surface of the substrate, thereby improving the uniformity of the plasma treatment process.

Claims (6)

A process chamber in which the plasma processing process is performed; An upper electrode and a lower electrode installed to face the inside of the process chamber; And a gas supply member supplying the processing gas to guide the flow of the processing gas from the side space around the substrate loaded between the upper electrode and the lower electrode toward the center portion. The method of claim 1, And an exhaust hole for exhausting a by-product generated during the process in the center of the lower electrode. The method according to claim 1 or 2, The device, And a cooling member coupled to an upper portion of the upper electrode and having a cooling line through which a cooling fluid is circulated so as to cool heat generated during plasma discharge. In the method of processing a substrate using a plasma, A substrate processing method comprising loading a substrate in a plasma processing region between an upper electrode and a lower electrode, and supplying a processing gas so that a flow of the processing gas is induced from a side space around the substrate to a central direction. . The method of claim 4, wherein The method, And by-products generated during the plasma processing process are exhausted through exhaust holes formed in the center of the lower electrode. The method of claim 5, wherein The method, And circulating a cooling fluid in a cooling line of a cooling member provided on an upper surface of the upper electrode to cool the heat of the upper electrode generated during plasma discharge.

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