KR101047862B1 - Substrate treatment apparatus using high pressure processor and gas recycling method of high pressure processor - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing apparatus using a high pressure processor, wherein the first and second branches respectively branch carbon dioxide from a high pressure processor for treating a substrate using high pressure carbon dioxide and a discharge pipe for discharging carbon dioxide used in the high pressure processor. The additive is separated from the carbon dioxide supplied through the branch line and the first branch line, and the carbon dioxide is condensed, and the refrigerant is fed through the second branch line together with the refrigerant circulation tube through which the refrigerant passes through the condensation. A recycling unit for causing a temperature drop due to adiabatic expansion, a high pressure pump for pumping the liquid carbon dioxide of the recycling unit or the carbon dioxide supply unit at a high pressure, and gradually heating the carbon dioxide boosted by the high pressure pump, First and second heating buffers acting as a supply buffer It includes. According to the present invention, the condensation process may be performed after separating the additives from the carbon dioxide used for cleaning by constructing an integrated single-unit recycling unit, thereby reducing the volume of the equipment, reducing the footprint, and reducing the number of inspection items. It has an effect.

Supercritical, High Pressure Cleaning, MEMS Dryer, Carbon Dioxide, Recycling

Description

Processing apparatus using high-pressure treating device and recycle method for the high-pressure treating device}

The present invention relates to a substrate processing apparatus using a high pressure processor and a gas recycling method of the high pressure processor, and in particular, a high pressure processor capable of reducing energy consumption and reducing footprint in a process for reusing carbon dioxide used for cleaning or drying. The present invention relates to a substrate recycling apparatus and a gas recycling method of a high pressure processor.

During the semiconductor manufacturing process, a cleaning process for removing foreign substances of organic or inorganic materials present on the semiconductor substrate is required.

These cleaning processes can be classified into wet cleaning and dry cleaning. Among them, wet cleaning has many aspects such as high aspect ratio, wetting in the microstructure by the cleaning liquid, watermark formation, and increasing the purification cost to increase the purity of the cleaning liquid. I have a problem.

In addition, dry cleaning is being developed by plasma, gas phase or supercritical dry cleaning technology. However, dry cleaning process by plasma is not easy to remove contaminants as well as concern that the substrate may be damaged by oxygen plasma. There was a problem that a process is required.

In addition, as another example of dry cleaning, a supercritical cleaning process for cleaning a substrate using a mixture of supercritical carbon dioxide and various cosolvents has been introduced.

However, it is impossible to form a homogeneous transparent phase by simply mixing a polar co-solvent with non-polar carbon dioxide in a supercritical state, which does not solve the problem of conventional wet cleaning, and the cleaning efficiency is low, even if a homogeneous transparent supercritical state is formed. There is a problem in that high cost is required as it requires an ultra high temperature of more than 100 ℃ and an ultra high pressure of more than 300 bar. In order to solve this problem, even when the surfactant is introduced, a separate mixer or an ultrasonic apparatus is required to form a homogeneous transparent phase in a supercritical state, and it takes a long time.

A supercritical substrate processing apparatus for solving such problems is described in Korean Patent No. 0753493, and the main description thereof will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a conventional substrate processing apparatus described in Korean Patent No. 0753493.

Referring to FIG. 1, a conventional substrate treating apparatus includes a high pressure processor 60, a gaseous carbon dioxide supply source 20 and a liquid carbon dioxide supply source 21 connected to the high pressure processor 60, and a high pressure pump for delivering carbon dioxide at a high pressure. 24, a cleaning additive source 25 for supplying the cleaning additive, a rinse additive source 26 for supplying the rinse additive, and a supply pipe L2, L3, L4 for heating carbon dioxide and the additive. Connected to the high pressure processor 60 and the heaters 31, 32, and 33 installed in the heater, a homogeneous transparent phase mixer 70 for supplying a predetermined amount of the cleaning additive while forming a homogeneous transparent phase mixture in a supercritical state. A pressure control valve 54 for maintaining a constant pressure, a separator 61 connected to the high pressure processor 60 to separate the mixture discharged from the high pressure processor 60 into gaseous carbon dioxide and a liquid additive, and a separated gas. On Pinterest And a off automatic valve (1 to 12) and the gas washing column 63 and the absorption column 64 and a carbon dioxide condensation tank 23 to condense and re-purified gas for purifying carbon dioxide, on.

As described above, the invention described in Korean Patent No. 0753493 uses a high-pressure processor 60 to clean a semiconductor substrate to be cleaned with carbon dioxide and an additive in a supercritical state, and then is used by using an on-off automatic valve 11. The carbon dioxide and the additives are discharged to the outside, or the separator 61, the gas washing column 63, the adsorption column 64 and the condensation vessel 23 are treated to reuse the used carbon dioxide in the washing process.

However, the separator 61, the gas cleaning column 63, the adsorption column 64, and the condensation vessel 23, which are provided independently of each other, are bulky, cause an increase in footprint, and increase in inspection target items. A new problem has arisen.

In addition, there is a problem that the maintenance cost increases because the amount of refrigerant used in the condensation process for the reuse of carbon dioxide.

In addition, after the cleaning is performed in the high pressure processor 60, the carbon dioxide is discharged and then, it takes a long time to increase the pressure of the high pressure processor 60, thus delaying the process time and thus reducing the productivity.

The problem to be solved by the present invention in view of the above problems is to provide a substrate processing apparatus and a gas recycling method of a high pressure processor using a high pressure processor capable of integrating devices for the reuse of carbon dioxide.

In addition, another object of the present invention is to provide a substrate processing apparatus and a gas recycling method of a high pressure processor using a high pressure processor that can reduce the amount of energy required to recycle carbon dioxide.

In addition, another problem to be solved by the present invention is to dualize the heating unit for heating the carbon dioxide, by using each heating unit as a supply buffer of carbon dioxide, to shorten the time required to increase the pressure of the high-pressure processor to the process pressure to improve productivity The present invention provides a substrate treatment apparatus using a high pressure processor and a gas recycling method of the high pressure processor.

Substrate processing apparatus using a high pressure processor of the present invention for solving the above problems, the high pressure processor for processing a substrate using a high pressure carbon dioxide, and each branching carbon dioxide from the discharge pipe for discharging the carbon dioxide used in the high pressure processor The second and second branch lines and the second branch line together with the refrigerant circulation pipe through which the additive is separated from the carbon dioxide supplied through the first branch line and condensed the carbon dioxide, the refrigerant passes through the condensation. Recycling unit to be involved in the temperature drop by the adiabatic expansion of the carbon dioxide supplied through the high-pressure pump for pumping the liquid carbon dioxide of the recycle unit or carbon dioxide supply unit at a high pressure, and heating the carbon dioxide boosted by the high pressure pump step by step And serves as a buffer for supplying the high pressure processor. It includes a first and second heating buffer portion.

In addition, the gas recycling method of the high-pressure processor of the present invention for solving the above problems, by branching the gas to be recycled in the high-pressure processor to adiabatic expansion of a portion of the branched gas, a portion of the other portion of the gas is adiabatic expansion By recycling by condensation using gas, the recycling efficiency can be improved.

In the present invention, the substrate treating apparatus and the gas recycling method using the high pressure processor comprise an integrated single-cycle recycling unit to separate additives from carbon dioxide used for cleaning or drying, and to process the condensation process, thereby reducing the volume of equipment. It has the effect of reducing the footprint, reducing the footprint, and reducing the number of checks.

In addition, the gas recycling method of the substrate processing apparatus and the high pressure processor using the high pressure processor of the present invention is used for the purpose of recycling the carbon dioxide by using it for condensation of the recycled carbon dioxide without directly discharging a part of the used carbon dioxide to the outside. Reducing the amount of refrigerant used has the effect of reducing the cost.

In addition, the gas treatment method of the substrate processing apparatus and the high pressure processor using the high pressure processor of the present invention, dual heating unit for heating the liquid carbon dioxide in a supercritical state to enable a stepwise increase in temperature, each heating unit as a supply buffer of carbon dioxide It is effective to prevent the pressure drop in the high pressure processor and to shorten the process time.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the gas treatment method of the substrate processing apparatus and the high pressure processor using the present invention high pressure processor as described above in detail.

2 is a block diagram of a substrate processing apparatus using the high pressure processor of the present invention.

Referring to FIG. 2, the substrate treating apparatus using the high pressure processor of the present invention includes a high pressure processor 100 for cleaning, rinsing or drying a substrate with supplied supercritical carbon dioxide and additives, and a carbon dioxide supply unit 400 for supplying liquid carbon dioxide. And, the discharge line (L1) for discharging the carbon dioxide and additives used for cleaning in the high-pressure processor (100), and the first and second branch line for branching the carbon dioxide and additives discharged through the discharge line (L1) ( L2 and L3 and the carbon dioxide and the additive supplied through the first branch line L2 are separated from each other, the separated carbon dioxide is purified, and the refrigerant of the cooling unit 300 and the second branch line ( Lisa condensing the purified carbon dioxide using carbon dioxide supplied through L3) and condensing the carbon dioxide supplied from the carbon dioxide supply unit 400 so as not to vaporize. High pressure pump 500 for supplying the clock portion 200, the carbon dioxide or the recycled carbon dioxide of the recycle unit 200 at a high pressure, and the first heating buffer unit for storing and heating the carbon dioxide supplied from the high pressure pump 500 610 and a second heating buffer 620 which receives and stores the carbon dioxide heated in the first heating buffer 610 and reheats it to a process temperature to supply the high pressure processor 100, and the carbon dioxide to be supplied. The cleaning additive supply unit 700 and the rinse additive supply unit 800 for selectively supplying the cleaning additive and the rinse additive, respectively.

Hereinafter, the configuration and operation of the substrate processing apparatus using the high pressure processor of the present invention configured as described above will be described in more detail.

First, during the initial cleaning process, the carbon dioxide of the carbon dioxide supply unit 400 is supplied through the valve V4 and the high pressure pump 500 through the recycle unit 200 does not vaporize the liquid carbon dioxide. The high pressure is supplied to the first heating buffer unit 610.

The liquid carbon dioxide of the carbon dioxide supply unit 400 may be vaporized even while moving through the line, and when the vaporized carbon dioxide is directly pumped through the high pressure pump 500 which is a liquid pump, the high pressure pump 500 may idle. have.

In order to prevent this, the carbon dioxide supply unit 400 is condensed in the recycle unit 200 through a line L4 connected to the recycle unit 200 including a function of condensing the recycled carbon dioxide, and the liquid carbon dioxide is the high pressure pump. To pump carbon dioxide by 500.

Then, the pressure of the carbon dioxide supplied to the first heating buffer unit 610 is about 150 to 300bar is appropriate, and the temperature is heated to 35 to 100 ℃.

In addition, the carbon dioxide heated in the first heating buffer 610 is supplied to the second heating buffer 620 again. The second heating buffer unit 620 heats the temperature of carbon dioxide to about 50 to 100 ° C. at a pressure of about 150 to 300 bar.

The pressure of the first heating buffer unit 610 and the second heating buffer unit 620 is higher than the pressure of 120 to 250 bar of the process pressure of the pressure processor 100, which means that the pressure is lost in the supply of carbon dioxide In addition to taking into consideration, after the cleaning is completed in the pressure processor 100, after the carbon dioxide and the additives are discharged to lower the pressure back to the process pressure to act quickly.

Then, the carbon dioxide whose heating and pressure are adjusted through the second heating buffer unit 620 is supplied to the high pressure processor 100 by changing its path according to a cleaning or rinsing process.

That is, when the cleaning process proceeds through the valve (V6, V8, V10) so as to pass through the cleaning additive mixing unit 700, the cleaning additive and the high pressure atmosphere introduced in advance into the cleaning additive mixing unit 700 Are mixed in the feed to the autoclave 100.

Alternatively, in order to proceed with the rinse process, the valves V8 and V10 are closed, and the carbon dioxide passed through the rinse additive mixing unit 800 through the valves V9 and V11 passes through the rinse additive mixing unit 800. It is mixed with the rinse additive previously supplied.

In this case, the valve V12 may be supplied through the cleaning additive mixing unit 700 during the rinsing process, and the treatment may make the atmosphere in the cleaning additive mixing unit 700 into a carbon dioxide atmosphere.

In addition, since the carbon dioxide is supplied at a sufficient pressure, there is no need to use a separate pump for supplying a high pressure of the additive in the cleaning additive supply unit 700 and the rinse additive supply unit 800, thus simplifying the installation and reducing the cost. Can be.

The supplied supercritical carbon dioxide and the cleaning additive or rinse additive added to the carbon dioxide are supplied to the pressure processor 100, and the plurality of substrates are simultaneously cleaned.

It can also be used as a drying device for microelectromechanical systems (MEMS), depending on the additives used. This is because the fluid in the supercritical state can be dried without damaging the structure of the microelectromechanical system.

The carbon dioxide and the additive after the cleaning, rinsing or drying treatment are discharged through the discharge pipe L1, and the discharge pipe L1 is branched by the first branch line L2 and the second branch line L3.

The first branch line L2 is for recycling carbon dioxide, and the second branch line L3 is used to condense the recycled carbon dioxide again.

The first branch line L2 and the second branch line L3 are connected to the recycling unit 200.

3 is a cross-sectional configuration diagram of a recycling portion of a substrate processing apparatus using the high pressure processor of the present invention.

Referring to FIG. 3, the recycling unit 200 includes a bundle tube unit 210 connected to the second branch line L3 at the center thereof and adiabatic expansion, and the cooling unit 300 around the bundle tube unit 210. Refrigerant circulation pipe 220 through which the refrigerant flows through), a partition wall 230 for separating the liquid carbon dioxide and the additive recycled spaced apart from the refrigerant circulation tube 220 by a predetermined distance, and the partition wall 230 and the outer wall 240 ) Is a ring-shaped gas-liquid separator 250 which is sequentially installed in the horizontal direction between the) and the gas carbon dioxide supplied through the first branch line (L2) is located downward from the upper side of the outer wall (240). It comprises a heater 270 to prevent the liquefaction of carbon dioxide.

And line (L4) is to allow the carbon dioxide to be condensed at the front end of the high-pressure pump 500 in order to prevent the vaporization of the liquid carbon dioxide supplied through the carbon dioxide supply unit 400.

Hereinafter, the configuration and operation of the recycling unit 200 of the substrate processing apparatus using the high pressure processor of the present invention configured as described above will be described in more detail.

First, the first branch line L1 is connected to a side surface of the outer wall 240 of the recycling unit 200, and the partition wall 230 is installed at a position spaced apart from the outer wall 240 by a predetermined distance.

The partition wall 230 is provided with a passage through which the upper side is spaced apart from the upper side of the outer wall 240 so that gaseous carbon dioxide can pass.

The carbon dioxide to be reused supplied through the first branch line L1 includes an additive of a liquid phase, which is separated by moving to a space formed by the outer wall 240 and the partition wall 230, in particular, the gas-liquid separator 250. It can be separated by to recycle high purity carbon dioxide.

The gas-liquid separator 250 may be a porous plate or an adsorption plate.

Contaminants removed during cleaning or rinsing with the additive are also collected and dropped into the space formed by the outer wall 240 and the partition wall 230.

At the end of the first branch line (L2) there is a risk of adiabatic expansion of carbon dioxide and gaseous carbon dioxide phase change into a liquid to compensate for the latent heat loss due to adiabatic expansion using a heater 270 to maintain the gas state In addition, the carbon dioxide, which is maintained in the gas state, may be easily moved to the outside of the bundle tube part 210 through the upper side of the partition wall 230 and the outer wall 240.

Since the bundle 210 has a large volume, heat exchange easily occurs, and thus, the carbon dioxide can be more effectively condensed with the smooth discharge of carbon dioxide by depressurization.

Then, the additive is separated, and the purified gas carbon dioxide is condensed by the refrigerant circulation tube 220 to become liquid carbon dioxide, which is discharged to the high pressure pump 500 through the drain line thereunder.

At this time, the bundle pipe portion 210 passes the gas carbon dioxide supplied through the second branch line (L3). At this time, the bundle tube portion 210 includes a plurality of pipes each end is connected to the second branch line (L3), the total sum of the cross-sectional area of the plurality of pipes is more than the second branch line (L3). The larger, the gas or liquid carbon dioxide is adiabatic expansion in the inside of the bundle tube portion 210 to be smoothly discharged to the gaseous carbon dioxide by heat exchange, and the temperature is lowered.

The bundle tube portion 210 serves to condense the gaseous carbon dioxide together with the refrigerant circulation tube 220 due to the carbon dioxide having a lower temperature.

This is to partially use the carbon dioxide used in the cleaning to simply serve as a refrigerant to the outside to reduce the amount of refrigerant or energy consumption of the cooling unit 300 circulated to the refrigerant circulation tube 220. It becomes possible.

Carbon dioxide passing through the bundle 210 is discharged to the outside, the condensed carbon dioxide is discharged as necessary, the high-pressure pump 500, the first heating buffer 610 and the second heating buffer 620 Through the high pressure processor 100 is supplied can be reused for cleaning.

As described above, the recycling unit 200 implements facilities that are conventionally separated and installed in the process chamber as a single device, but by implementing a structure capable of minimizing its volume, thereby reducing the footprint and the number of inspection items of the facility. Can be reduced.

In addition, the latent heat loss generated during the adiabatic expansion of the gaseous carbon dioxide discharged to the outside together with the refrigerant may contribute to condensation of the carbon dioxide to be reused, thereby reducing energy use.

The liquid carbon dioxide condensed in the recycling unit 200 is selectively supplied to the high pressure processor 100 and used again for cleaning.

1 is a block diagram of a conventional substrate processing apparatus.

2 is a block diagram of a substrate processing apparatus using the high pressure processor of the present invention.

3 is a cross-sectional configuration diagram of a recycling unit used in the high pressure processor of the present invention.

* Description of the symbols for the main parts of the drawings *

100: high pressure processor 200: recycling part

210: bundle tube portion 220: refrigerant circulation tube

230: partition 240: outer wall

250: gas-liquid separator 260: adsorption plate

270: heater 300: cooling unit

400: carbon dioxide supply unit 500: high pressure pump

610: first heating buffer unit 620: second heating buffer unit

700: cleaning additive mixing unit 800: rinse additive mixing unit

Claims (7)

Branching the gas discharged from the discharge pipe of the high pressure processor through the first branch line and the second branch line; Adiabatic expansion of the gas branched through the first branch line, and condensing the adiabatic expansion gas into a gas branched through the second branch line; And And supplying the condensed gas to the autoclave. The method of claim 1, Gas diverged through the second branch line, the treatment gas recycling method of the high pressure treatment device, characterized in that the additive is removed before condensation. A high pressure processor for treating the substrate using high pressure carbon dioxide; First and second branch lines which branch carbon dioxide from a discharge pipe for discharging carbon dioxide used in the high pressure processor; The additive is separated from the carbon dioxide supplied through the first branch line and condensed, and the temperature drop due to the adiabatic expansion of the carbon dioxide supplied through the second branch line together with the refrigerant circulation tube through which the refrigerant passes through the condenser is condensed. Recycling unit to be involved; A high pressure pump for pumping liquid carbon dioxide at the recycle unit or the carbon dioxide supply unit at a high pressure; And Substrate heating apparatus using a high-pressure processor comprising a first and a second heating buffer portion for heating the carbon dioxide boosted through the high-pressure pump step by step, and serves as a buffer for supplying to the high-pressure processor. The method of claim 3, The recycling unit, A bundle pipe portion connected to the second branch line to thermally expand and expand carbon dioxide used for cleaning; A refrigerant circulation tube configured to allow a refrigerant to flow around the bundle tube part; A barrier rib separating the collected liquid carbon dioxide and the additive by being spaced apart from the refrigerant circulation pipe by a predetermined distance; A ring-shaped gas-liquid separator sequentially installed in the horizontal direction between the partition and the outer wall; And And a heater positioned downward from an upper side of the outer wall to heat gaseous carbon dioxide supplied through the first branch line to prevent liquefaction of carbon dioxide. 5. The method of claim 4, The bundle tube portion, One side includes a plurality of pipes connected to the second branch line, the sum of the cross-sectional area of the plurality of pipes substrate processing apparatus using a high pressure processor, characterized in that larger than the cross-sectional area of the second branch line. The method according to any one of claims 3 to 5, The first and second heating buffer unit, When the carbon dioxide used for cleaning in the high-pressure processor is discharged through the discharge pipe to lower the pressure, the high pressure to maintain a pressure higher than the process pressure so that the pressure of the high-pressure processor can be increased to the process pressure more quickly Substrate treatment apparatus using a processor. The method of claim 6, Further comprising a cleaning additive supply unit and a rinsing additive mixing unit for selectively mixing and supplying a cleaning additive or rinse additive to the carbon dioxide supplied to the high-pressure processor through the second heating buffer unit, a separate for supplying the cleaning additive or rinse additive The substrate processing apparatus using the high pressure processor, characterized in that the high-pressure carbon dioxide directly passes through the cleaning additive supply unit or the rinse additive mixing unit so as not to use the pump.

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