JP2011194345A - Solid-liquid separator and substrate treating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To a solid-liquid separator, even which is a simple constitution, capable of certainly separating, and recovering, particles from a treated liquid mixing particles of a substrate, and to provide a substrate treating apparatus equipped with this solid-liquid separator.SOLUTION: The separator includes a storage tank 12 storing a treated liquid mixing particles, a defoaming tank 13, an exhaust gas damper 32 exhausting gas in the defoaming tank 13, a connecting pipe passage 14 connecting the storage tank 12 and the defoaming tank 13, a surfactant storage tank 15 storing a surfactant, a gas feed passage 46 making gas mix in circulation passage of the treated liquid consisting of a mixing nozzle 31 and a circulation pipe passage 47, a vacuum pump 29 decompressing a space in the defoaming tank 13, and a heater 33 heating the inner space of the defoaming tank 13.

Description

  The present invention relates to a solid-liquid separation apparatus that separates and collects particles from a processing liquid mixed with substrate particles, and a substrate processing apparatus including the solid-liquid separation apparatus.

In a substrate processing apparatus that polishes or grinds a substrate, a processing liquid mixed with substrate particles is discharged. For example, in a substrate processing apparatus that performs chemical mechanical polishing called CMP (Chemical Mechanical Polishing) on a semiconductor wafer, a processing liquid containing silicon (Si) or silica (SiO ₂ ) particles is discharged. . Such a treatment liquid is preferably not reused as a waste liquid, but is reused in a state in which the particles are removed from the treatment liquid and the treatment liquid is separated from the particles.

  For this reason, conventionally, in order to perform such solid-liquid separation, a precipitation process for precipitating the particle component and a filter process for filtering the particle component are performed. However, in the precipitation treatment, it takes a long time for the particles dispersed in the treatment liquid to settle. Further, in the filter treatment, there is a problem that the filter is clogged with particles, and the filter needs to be replaced frequently.

  In Patent Document 1, the water to be treated and water containing microbubbles are mixed and introduced into a pressurized flotation device, and the suspended substance floating on the water surface in the pressurized flotation tank is collected by a scraper having a rotary scraper. Has been proposed.

JP 2009-34683 A

  In the water treatment apparatus described in Patent Document 1 described above, it is extremely difficult to remove only suspended substances from the upper surface of the water to be treated, and the suspended substances and the water to be treated can be reliably separated and recovered. It becomes impossible.

  The present invention has been made to solve the above-described problems, and has a simple configuration, and a solid-liquid separation device capable of reliably separating and recovering particles from a processing liquid mixed with particles on a substrate, and An object of the present invention is to provide a substrate processing apparatus provided with this solid-liquid separator.

  The invention according to claim 1 is a solid-liquid separation device that separates and recovers particles from a processing liquid in which particles of a substrate are mixed, a storage tank that stores the processing liquid in which particles are mixed, a defoaming tank, , An exhaust means for exhausting the gas in the defoaming tank, a connection line connecting the storage tank and the defoaming tank, and foaming for foaming bubbles containing particles from the processing liquid stored in the storage tank And a defoaming means for extinguishing the bubbles generated by the action of the foaming mechanism and entering the defoaming tank through the connection pipe line.

  The invention described in claim 2 is the invention described in claim 1, further comprising a surfactant supply mechanism for supplying a surfactant into the storage tank.

  According to a third aspect of the present invention, in the invention of the second aspect, the foaming mechanism includes a circulation path for circulating the treatment liquid in the storage tank, and a gas supply for mixing gas into the circulation path. Road.

  The invention described in claim 4 is the heating mechanism according to claim 3, wherein the defoaming means heats the inside of the defoaming tank.

  According to a fifth aspect of the present invention, in the third aspect of the present invention, the defoaming means is a pressure reducing mechanism that depressurizes the inside of the defoaming tank.

  The invention described in claim 6 includes a substrate processing apparatus that polishes or grinds the substrate, and a solid-liquid separation apparatus according to any one of claims 1 to 5.

  According to the first aspect of the present invention, it is possible to reliably separate and recover the particles from the processing liquid in which the particles of the substrate are mixed, while having a simple configuration.

  According to invention of Claim 2, it becomes possible to foam more effectively the foam containing particle | grains from a process liquid in a storage tank by the effect | action of surfactant.

  According to the third aspect of the present invention, the foaming mechanism including the circulation path and the gas supply path makes it possible to more effectively foam bubbles including particles from the treatment liquid in the storage tank.

  According to the invention described in claim 4, it is possible to quickly eliminate the bubbles by the heating mechanism.

  According to the fifth aspect of the present invention, it is possible to quickly eliminate the bubbles by the pressure reducing mechanism.

  According to the sixth aspect of the present invention, the particles are separated in-line by the solid-liquid separation device with respect to the processing liquid mixed with the substrate particles discharged from the substrate processing apparatus for polishing or grinding the substrate. It becomes possible to collect.

1 is a schematic view showing a solid-liquid separation apparatus according to the present invention together with a substrate processing apparatus 11. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing a solid-liquid separation apparatus according to the present invention together with a substrate processing apparatus 11.

  The solid-liquid separation apparatus according to the present invention is for separating and recovering particles from a processing liquid mixed with substrate particles discharged from the substrate processing apparatus 11. The substrate processing apparatus 11 performs, for example, grinding or chemical mechanical polishing called CMP on a semiconductor wafer. The substrate processing apparatus 11 and the solid-liquid separation apparatus constitute a substrate processing apparatus according to the present invention.

  The solid-liquid separation device includes a storage tank 12 that stores a processing liquid mixed with substrate particles discharged from the substrate processing apparatus 11, an antifoaming tank 13, and the storage tank 12 and the antifoaming tank 13. A connecting pipe line 14 to be connected and a surfactant storage tank 15 for storing a surfactant such as a detergent are provided. The substrate processing apparatus 11 and the storage tank 12 are connected by a pipeline 42 having an electromagnetic on-off valve 21. The surfactant storage tank 15 and the storage tank 12 are connected by a pipeline 41 having an electromagnetic on-off valve 22. In addition, an electromagnetic on-off valve 23 is disposed in the connection pipeline 14.

  In the storage tank 12, the mixing nozzle 31 is disposed in a state of being immersed in the processing liquid stored therein. The mixing nozzle 31 includes a circulation pump 28, and a gas is introduced into a circulation line 47 for circulating the treatment liquid in the storage tank 12 and a treatment liquid circulation path constituted by the mixing nozzle 31 and the circulation line 47. A gas supply path 46 having an electromagnetic opening / closing valve 26 for mixing is connected. In addition, the storage tank 12 is connected to a drainage unit (not shown) via a pipe line 48 provided with an electromagnetic opening / closing valve 27.

  The defoaming tank 13 is provided with an exhaust damper 32 that exhausts the gas in the defoaming tank 13 from above. The defoaming tank 13 is connected to a vacuum pump 29 that depressurizes the space inside the defoaming tank 13 via a conduit 43. Further, a heater 33 for heating the internal space of the defoaming tank 13 is disposed in the defoaming tank 13. Further, a discharge port (not shown) is formed at the lower end portion of the defoaming tank. The discharge port is connected to the conduit 44 reaching the storage tank 12 via the electromagnetic open / close valve 24 and the electromagnetic open / close valve 25. And a pipe 45 leading to a drainage portion (not shown).

  In the solid-liquid separation apparatus having the above-described configuration, the processing liquid mixed with the substrate particles is sent from the substrate processing apparatus 11 to the storage tank 12 through the pipeline 42 and stored in the storage tank 12. The In addition, a surfactant such as a detergent is supplied from the surfactant storage tank 15 through the pipeline 41 to the processing liquid stored in the storage tank 12.

  In such a state, the processing liquid stored in the storage tank 12 circulates in the circulation path composed of the circulation pipe 47 and the mixing nozzle 31 by driving the circulation pump 28, and the electromagnetic on-off valve 26 is opened to circulate. Outside air is mixed into the processing liquid. Thereby, bubbles are generated in the treatment liquid containing the surfactant. For example, the bubbles are microbubbles having a very small size. However, the size of the bubbles is larger than the substrate particles of about several microns to several tens of microns existing in the processing liquid. For this reason, the particles in the treatment liquid are captured on the surface of the bubbles.

  At the same time, in the defoaming tank 13, the inside of the tank is slightly depressurized by the action of the exhaust damper 32 and the inside of the tank is heated by the action of the heater 33. For this reason, the bubbles containing the substrate particles generated in the storage tank 12 enter the defoaming tank 13 from the storage tank 12 through the connection line 14 due to the depressurization action of the defoaming tank 13. The bubbles are expanded by the heating action of the heater 33 and broken.

  In addition, when bubbles are filled in the defoaming tank 13 in spite of the heating action by the heater 33, the defoaming is performed by the action of the vacuum pump 29 with the electromagnetic on-off valve 23 in the connection line 14 closed. The atmospheric pressure in the tank 13 is made extremely low. Thereby, the gas inside the bubbles can be expanded, and the bubbles in the defoaming tank 13 can be quickly broken.

  If the bubbles in the defoaming tank 13 are broken, a small amount of processing liquid is accumulated at the bottom of the defoaming tank 13 together with the particles of the substrate. The particles on the substrate are discharged from the defoaming tank 13 by the operator, or are discharged from the defoaming tank 13 through the conduit 45.

  As described above, according to the solid-liquid separation apparatus according to the present invention, bubbles including the substrate particles generated in the storage tank 12 are introduced into the defoaming tank 13, and the heating mechanism and the vacuum pump using the heater 33 are used for the bubbles. 29, the defoaming tank 13 depressurizes the inside of the defoaming tank 13, so that the particles can be reliably separated and recovered from the processing liquid mixed with the substrate particles discharged from the substrate processing apparatus 11. It becomes possible.

  In the above-described embodiment, as a defoaming unit that erases the foam stored in the foam tank 13, a heating mechanism using the heater 33 and a decompression mechanism that decompresses the interior of the defoaming tank 13 by the vacuum pump 29. Both are used, but only one of these may be used. Moreover, you may use things other than these as a defoaming means.

DESCRIPTION OF SYMBOLS 11 Substrate processing apparatus 12 Storage tank 13 Defoaming tank 14 Connection pipe line 15 Surfactant storage tank 28 Circulation pump 29 Vacuum pump 31 Mixing nozzle 32 Exhaust damper 33 Heater

Claims (6)

A solid-liquid separation device for separating and recovering particles from a processing liquid mixed with substrate particles,
A storage tank for storing a processing liquid mixed with particles;
A defoaming tank,
Exhaust means for exhausting the gas in the defoaming tank;
A connection line connecting the storage tank and the defoaming tank;
A foaming mechanism for foaming bubbles containing particles from the processing liquid stored in the storage tank;
Defoaming means for removing the foam generated by the action of the foaming mechanism and entering the defoaming tank through the connection pipe line,
A solid-liquid separation device comprising: The solid-liquid separator according to claim 1,
A solid-liquid separator comprising a surfactant supply mechanism for supplying a surfactant into the storage tank. The solid-liquid separator according to claim 2,
The foaming mechanism is
A circulation path for circulating the treatment liquid in the storage tank;
A gas supply path for mixing gas in the circulation path;
A solid-liquid separator comprising: In the solid-liquid separation device according to claim 3,
The defoaming means is a solid-liquid separation device that is a heating mechanism for heating the inside of the defoaming tank. In the solid-liquid separation device according to claim 3,
The defoaming means is a solid-liquid separator that is a decompression mechanism for decompressing the inside of the defoaming tank. A substrate processing apparatus for polishing or grinding the substrate;
A solid-liquid separation device according to any one of claims 1 to 5,
A substrate processing apparatus comprising:

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