KR100674735B1 - Substrate cleaning apparatus and method - Google Patents

Abstract

Provided is a substrate cleaning apparatus capable of sufficiently removing foreign substances attached to the back side of a substrate without damaging the substrate.

The plasma processing apparatus 1 as the substrate cleaning apparatus is disposed in the chamber 10, the susceptor 11 disposed on the chamber 10, and the susceptor 11 on which the wafer W is mounted, and the susceptor 11. The electrode plate 20 to be applied, the rough exhaust line which exhausts the inside of the chamber 10, the pusher pin 30 which creates a space S between the susceptor 11 and the wafer W, and the N ₂ gas in the space S. A heat conduction gas supply hole 27 for supplying gas and a shower head 33 for introducing a processing gas or the like into the chamber 10, and when the space S is generated, the electrode plate 20 has a high voltage of different polarity. is applied to this shift, N ₂ gas is ejected toward the back of the wafer W in the space S, and when there is an exhaust that chamber 10, also, the chamber 10 I and the pressure, N ₂ into the chamber 10 Gas is introduced.

Description

Substrate Cleaning Device and Substrate Cleaning Method {SUBSTRATE CLEANING APPARATUS AND METHOD}

1 is a cross-sectional view showing a schematic configuration of a plasma processing apparatus as a substrate cleaning apparatus according to a first embodiment of the present invention.

2 is a sequential diagram of a substrate cleaning process performed in the plasma processing apparatus of FIG.

3 is a diagram showing a schematic configuration of a pusher pin in a plasma processing apparatus as a substrate cleaning apparatus according to a second embodiment of the present invention.

4 is a cross-sectional view showing a schematic configuration of a substrate cleaning apparatus according to a third embodiment of the present invention.

5 is a diagram illustrating a schematic configuration of a substrate processing system in which the substrate processing apparatus of FIG. 4 is disposed.

6A to 6C are views schematically showing the removal of particles from the back surface of the wafer in the embodiment of the present invention, and FIG. 6A is directed to the electrode plate 20 while the valve V1 is open. It is a figure which shows typically the shape of the space S when voltage of + 2kV and -2kV is alternately repeated, and FIG. 6B is a figure which shows typically the state of space S after several seconds passed from FIG. 6A. 6C is a diagram schematically showing a state of the space S after several seconds have elapsed since FIG. 6B.

It is a graph which shows the removal observation result of the particle in the Example of this invention.

8 is a diagram showing a schematic configuration of a plasma processing apparatus for performing an etching process on a conventional wafer W. FIG.

Explanation of symbols for the main parts of the drawings

1,56: plasma processing apparatus 10,43: chamber

11: susceptor 12,65: exhaust passage

13: baffle plate 14: APC

15: TMP 16,46: DP

17,45 exhaust pipe 18 high frequency power supply

19: matching device 20, 35, 47: electrode plate

22,41,48: DC power supply 24: focus ring

25: refrigerant chamber 26: piping

27: electrothermal gas supply hole 28: electrothermal gas supply line

29: electrothermal gas supply pipe 30, 40: pusher pin

31, 52: inlet and outlet 32, 53: gate valve

33: shower head 34: gas vent hole

36 electrode support 37 buffer chamber

38: process gas introduction pipe 39: magnet

42 substrate cleaning device 44 stage

49: gas supply hole 50: gas supply line

51: pin 54: gas introduction pipe

55 substrate processing system 57, 62 carrier arm

58: load, lockroom 59: processship

60: Roadboat 61: Orient

63: loader module 64: gas supply pipe

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate cleaning apparatus and a substrate cleaning method, and more particularly, to a substrate cleaning apparatus and a substrate cleaning method for removing foreign substances adhering to the back surface of a substrate subjected to plasma treatment.

Usually, in the manufacturing process of a semiconductor device, processing using plasma, such as etching, sputtering, and CVD (chemical vapor growth), with respect to the semiconductor wafer (henceforth a "wafer") which is a to-be-processed object is called "plasma processing." Is performed).

For example, in order to perform an etching process, the plasma processing apparatus 80 is arrange | positioned inside the cylindrical container 81 which accommodates a wafer, and the said cylindrical container 81, as shown in FIG. And a pusher pin 83 arranged to pass through the susceptor 82 toward a surface on which the wafer is mounted (hereinafter referred to as a "mounting surface") on which the wafer is mounted. The susceptor 82 has, on the mounting surface, an electrostatic chuck 85 for arranging electrodes connected to the direct current power source 84 and further includes a lower electrode (connected to the high frequency power source 86). 87) (see, eg, Patent Document 1).

In the plasma processing apparatus 80, after the electrostatic chuck 85 adsorbs the wafer to the mounting surface due to the electrostatic attraction force, high frequency power is applied to the lower electrode 87, so that the upper surface and the susceptor (in the cylindrical container 81) ( A high frequency electric field is generated between 82, and the processing gas introduced into the cylindrical container 81 is dissociated to generate plasma. The generated plasma is received on the surface of the wafer by a focus ring (not shown) disposed to surround the wafer, and the oxide film or the like formed on the surface of the wafer is etched.

In addition, the wafer subjected to the etching treatment is lifted from the mounting surface by the pusher pin 83, and the cylindrical container 81 is carried by a conveying device (not shown) such as a scalar arm that enters the cylindrical container 81. Exported from

Among the plasma generated in the etching process, those which are not received on the surface of the wafer collide with the inner wall of the cylindrical container 81 to generate particles. In addition, in the etching treatment, a reaction product is generated. Most of these particles and reaction products are discharged from the cylindrical container 81 by an exhaust device (not shown), but part of the particles or reaction products accumulated in the cylindrical container 81 are deposited on the mounting surface. In addition, particles in which the susceptor 82 oscillates due to plasma or the like are also deposited on the mounting surface. Particles and reaction products deposited on these mounting surfaces adhere to the back surface of the wafer as foreign matter when the wafer is mounted on the mounting surface. As a method for removing particles or reaction products attached to the back surface of the wafer, wet cleaning using a cleaning solution or the like is known.

In addition, as a method without using the cleaning liquid, plasma is generated between the wafer lifted by the pusher pin and the mounting surface, and the back surface of the wafer is caused by the sputtering by the generated ions of the plasma or the chemical reaction by radicals. The removal method of removing the particle | grains of is also known (for example, refer patent document 2).

[Patent Document 1] Japanese Patent Laid-Open Publication No. 5-226291 (Fig. 1).

[Patent Document 2] Specification of US Patent No. 4962049 (Second Section No. 67 Line-Third Column No. 17 Line)

However, half the wet cleaning contaminates the cleaning liquid. Therefore, there has been a problem that the surface of the wafer is contaminated by particles or the like contained in the cleaning liquid contaminated in wet cleaning. In addition, when the wafer subjected to the etching treatment was carried into a chamber or the like of the next step, particles not removed sometimes contaminated the inside of the chamfer.

In addition, when the particles on the back side of the wafer are removed by the plasma, the plasma generated is subjected to excessive plasma treatment to damage the wafer, for example, excessive etching treatment to the wafer surface results in overetching. There was a problem.

An object of the present invention is to provide a substrate cleaning apparatus and a substrate cleaning method which can sufficiently remove foreign substances adhering to the back surface of a substrate without damaging the substrate.

In order to achieve the above object, the substrate cleaning window according to claim 1 includes a storage chamber accommodating a substrate, a mounting table disposed in the storage chamber, and a mounting table on which the substrate is mounted, and a voltage applied thereto. A positive device for adsorbing the substrate to the mounting table, an exhaust device for evacuating the inside of the storage chamber, a separation device for generating a space between the mounting table and the substrate to generate a space between the mounting table and the substrate; A gas supply device for supplying a gas, when the space is generated, a voltage is applied to the electrode, the gas supply device supplies gas to the space, and the exhaust device exhausts the inside of the storage chamber. It is characterized by.

The substrate cleaning apparatus according to claim 2, further comprising a gas introduction section for introducing gas into the storage chamber when the inside of the storage chamber is depressurized and the space is generated. It is done.

The substrate cleaning device according to claim 3 is characterized in that, in the substrate cleaning device according to claim 1 or 2, a voltage is discontinuously applied to the electrode.

The substrate cleaning apparatus described in claim 4 is characterized in that, in the substrate cleaning apparatus according to claim 3, voltages having different polarities are alternately applied to the electrodes.

The substrate cleaning device according to claim 5 is the substrate cleaning device according to claim 4, wherein an absolute value of the voltage is 500 V or more.

The substrate cleaning apparatus of claim 6 is the substrate cleaning apparatus of claim 5, wherein an absolute value of the voltage is 2 kV or more.

The substrate cleaning apparatus according to claim 7 is the substrate cleaning apparatus according to any one of claims 1 to 6, wherein the exhaust device maintains the pressure in the storage chamber at 133 Pa or more when the space is generated. It features.

The substrate cleaning device according to claim 8 is the substrate cleaning device according to claim 7, wherein the exhaust device has a pressure within the range of 1.33 × 10 ³ to 1.33 × 10 ⁴ Pa when the space is generated. It is characterized by maintaining as.

In order to achieve the above object, the substrate cleaning device according to claim 9 includes a storage chamber accommodating a substrate, a mounting table disposed in the storage chamber, on which the substrate is mounted, an exhaust device for exhausting the interior of the storage chamber, and A spacing device that separates the mounting table from the substrate to create a space between the mounting table and the substrate, and contacts the substrate to apply a voltage to the substrate; a gas supply device supplying gas to the space; A gas introduction portion for introducing gas into the storage chamber, when the space is generated, a voltage is applied to the substrate, the gas supply device supplies gas to the space, and the exhaust device is inside the storage chamber. Exhaust gas, and when the inside of the storage chamber is depressurized and the space is generated, the gas introduction section introduces gas into the storage chamber. And that is characterized.

In order to achieve the above object, the substrate cleaning method according to claim 10, the substrate cleaning method for removing the foreign matter adhering to the back of the substrate, the accommodating step for accommodating the substrate in the storage chamber, and the substrate in the storage chamber A mounting step of mounting on the mounted table and a separation step of separating the mounting table and the substrate so that a space is formed between the mounting table and the substrate, and when the space is generated, A voltage applying step of applying a voltage to an electrode, a gas supplying step of supplying gas to the space when the space is generated, and an exhausting step of exhausting the inside of the storage chamber when the space is generated. It features.

The substrate cleaning method according to claim 11, wherein the substrate cleaning method according to claim 10 further includes a gas introduction step of introducing gas into the storage chamber when the inside of the storage chamber is depressurized and the space is generated. It features.

The substrate cleaning method according to claim 12 is the substrate cleaning method according to claim 10, wherein in the voltage application step, a voltage is discontinuously applied to the electrode.

The substrate cleaning method of claim 13 is the substrate cleaning method of claim 12, wherein in the voltage application step, voltages having different polarities are alternately applied to the electrodes.

In order to achieve the above object, the substrate cleaning method according to claim 14, in the substrate cleaning method for removing the foreign matter attached to the back of the substrate, the accommodating step for accommodating the substrate in the storage chamber, and the substrate in the storage chamber A mounting step of mounting the mounted table, a separation step of separating the mounting table and the substrate so that a space is generated between the mounting table and the substrate, and when the space is generated, a voltage is applied to the substrate. A voltage applying step to be applied, an exhausting step to exhaust the inside of the storage chamber when the space is generated, and a gas for introducing gas into the storage chamber when the inside of the storage chamber is depressurized and the space is generated. It is characterized by having an introduction step.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings.

First, the plasma processing apparatus as the substrate cleaning apparatus according to the first embodiment of the present invention will be described in detail.

1 is a cross-sectional view showing a schematic configuration of a plasma processing apparatus as a substrate cleaning apparatus according to a first embodiment of the present invention.

In Fig. 1, the plasma processing apparatus 1 constituted as an etching processing apparatus for etching a wafer W has a cylindrical chamber (receiving chamber) 10 made of a metal, for example, aluminum or stainless steel, and the chamber In the column 10, a cylindrical susceptor (mounting table) 11 as a stage for mounting the wafer W is disposed.

Between the side wall of the chamber 10 and the susceptor 11, an exhaust passage 12 is formed that functions as a flow path for discharging gas above the susceptor 11 out of the chamber 10. An annular baffle plate 13 is disposed in the middle of the exhaust passage 12, and a space downstream from the baffle plate 13 of the exhaust passage 12 is a variable butterfly valve. valve) (hereinafter referred to as "APC") (14). The APC 14 is connected to a turbomolecular pump (hereinafter referred to as "TMP") 15 which is an exhaust pump for vacuum exhaust, and a dry pump (hereinafter referred to as "DP") which is an exhaust pump via the TMP 15. 16). The exhaust flow path constituted by the APC 14, the TMP 15, and the DP 16 is hereinafter referred to as the "main exhaust line", but this main exhaust line is controlled by the APC 14 to control the pressure in the chamber 10. In addition to the above, the pressure is reduced by the TMP 15 and the DP 16 until the chamber 10 is almost vacuumed.

Further, a space downstream of the baffle plate 13 of the exhaust passage 12 described above is connected to an exhaust passage (hereinafter referred to as "rough exhaust line") (exhaust system) separate from the exhaust line. This rough exhaust line is provided with the exhaust pipe 17 whose diameter is 25 mm, for example, which communicates the said space and DP 16, and the valve V2 arrange | positioned in the middle of the exhaust pipe 17. As shown in FIG. The valve V2 can block the space and the DP 16. The rough exhaust line exhausts gas in chamber 10 by DP 16.

The susceptor 11 is electrically connected to a high frequency power source 18 for plasma generation via a matching device 19. The high frequency power source 18 applies a high frequency power of a predetermined high frequency, for example, 13.56 MHz, to the susceptor 11. For this reason, the susceptor 11 functions as a lower electrode.

In the upper part of the susceptor 11, the disk-shaped electrode plate 20 which consists of a conductive film is arrange | positioned in order to adsorb | suck the wafer W by electrostatic attraction force. The DC power supply 22 is electrically connected to the electrode plate 20.

The wafer W is adsorbed and held on the upper surface of the susceptor 11 by a Coulomb force or Johnson-Rahbek force generated by a DC voltage applied from the DC power supply 22 to the electrode plate 20. . The annular focus ring 24 made of silicon (Si) or the like converges the plasma generated above the susceptor 11 toward the wafer W. As shown in FIG.

In addition, inside the susceptor 11, for example, a coolant chamber 25 having a ring phenomenon extending in the circumferential direction is provided. The refrigerant chamber 25 is circulated with a predetermined temperature, for example, cooling water, from a chiller unit (not shown) via a pipe 26, and the temperature of the wafer W on the susceptor 11 is changed by the temperature of the refrigerant. The processing temperature is controlled.

A plurality of heat conductive gas supply holes (gas supply devices) 27 are opened in the portion where the wafer W is adsorbed on the upper surface of the susceptor 11. These heat conduction gas supply holes 27 communicate with the heat conduction gas supply pipe 29 having the valve V3 via the heat conduction gas supply line 28 disposed inside the susceptor 11 and connect to the heat conduction gas supply pipe 29. The heat conduction gas, for example, He gas, from the connected heat conduction gas supply unit (not shown) is supplied between the upper surface of the susceptor 11 and the rear surface of the wafer W. Thereby, the heat transfer property of the wafer W and the susceptor 11 improves. Moreover, the valve V3 can block the heat conduction gas supply hole 27 and the heat conduction gas supply part.

In addition, a plurality of pusher pins (separator) 30 as lift pins freely protruding from the upper surface of the susceptor 11 are disposed at the portion where the wafer W is adsorbed on the upper surface of the susceptor 11. . These pusher pins 30 are moved upward and downward in the drawing by rotating the motor (not shown) into a linear motion by a ball screw or the like. When the wafer W is adsorbed and held on the upper surface of the susceptor 11, the pusher pin 30 is accommodated in the susceptor 11, and the wafer W is finished by the plasma treatment, such as etching is performed. When carrying out from the rod, the pusher pin 30 protrudes from the upper surface of the susceptor 11 to lift the wafer W away from the susceptor 11 and lifts upwards. At this time, a space S is formed between the upper surface of the susceptor 11 and the rear surface of the wafer W.

The gate valve 32 which opens and closes the opening-and-exiting 31 of the wafer W is mounted in the side wall of the chamber 10. In the ceiling of the chamber 10, a shower head 33 serving as an upper electrode at a ground potential is disposed. Accordingly, the high frequency voltage from the high frequency power source 18 is applied between the susceptor 11 and the shower head 33.

The shower head 33 of the ceiling portion has an electrode plate 35 on the lower surface having a plurality of gas air holes 34 and an electrode support 36 for detachably supporting the electrode plate 35. A buffer chamber 37 is provided inside the electrode support 36, and a processing gas introduction pipe 38 from a processing gas supply unit (not shown) is connected to the buffer chamber 37. The valve V1 is disposed in the middle of the processing gas introduction pipe 38. This valve V1 can block the buffer chamber 37 and a process gas supply part. Further, around the chamber 10, a magnet 3P extending in an annular or concentric shape is disposed.

In the chamber 10 of the plasma processing apparatus 1, a horizontal magnetic field directed in one direction is formed by the magnet 39, and by a high frequency voltage applied between the susceptor 11 and the shower head 33. An RF electric field is formed in the vertical direction, whereby magnetron discharge through the processing gas is performed in the chamber 10, and a high density plasma is generated from the processing gas in the vicinity of the surface of the susceptor 11.

In the plasma processing apparatus 1, during the etching process, the gate W 32 is first opened, and the wafer W to be processed is loaded into the chamber 10 and mounted on the susceptor 11. Then, the processing gas (for example, a mixed gas consisting of C ₄ F ₈ gas, O ₂ gas and Ar gas at a predetermined flow rate) is introduced into the chamber 10 from the shower head 33 at a predetermined flow rate and flow rate ratio, The pressure in the chamber 10 is set to a predetermined value by the APC 14 or the like. In addition, the high frequency power is supplied from the high frequency power source 18 to the susceptor 11, and a direct current voltage is applied to the electrode plate 20 from the direct current power source 22 to suck the wafer W onto the susceptor 11. . The process gas discharged from the shower head 33 is converted into plasma as described above. Radicals and ions generated by the plasma converge on the surface of the wafer W by the focus ring 24 to etch the surface of the wafer W. As shown in FIG.

In the above-described plasma processing apparatus 1, those that do not converge to the surface of the wafer W among the generated plasma collide with the inner wall of the chamber 10 to generate particles. Particles which are not discharged by the present exhaust line or the rough exhaust line are deposited on the upper surface of the susceptor 11 among the generated particles. The particles deposited on the upper surface adhere to the back surface of the wafer W as foreign matter when the wafer W is mounted on the upper surface of the susceptor 11. Correspondingly, in the plasma processing apparatus 1, after the etching treatment is performed on the wafer W, when the wafer W is separated from the upper surface of the susceptor 11 by the pusher pin 30, a space S is generated. The high voltage is applied to the electrode plate 20, the N ₂ gas or the like is supplied from the heat conduction gas supply hole 27 to the space S, and the inside of the chamber 10 is exhausted by a rough exhaust line. In addition, the process gas is introduced into the chamber 10 from the shower head 33 while the inside of the chamber 10 is being decompressed by the rough exhaust line. As a result, particles adhering to the back surface of the wafer W are eliminated. The substrate cleaning method for excluding particles adhering to the back surface of the wafer W, which is executed in the plasma processing apparatus 1, will be described below.

FIG. 2 is a sequential diagram of a substrate cleaning process performed in the plasma processing apparatus of FIG. 1. This substrate cleaning process is performed after the etching process is performed on the wafer W. FIG.

In FIG. 2, the precondition for which this process is performed is that the wafer W is subjected to the etching process and is mounted on the upper surface of the susceptor 11, and no voltage is applied to the electrode plate 20 ( HV 0), the APC 14 is open (APC OPEN), and the TMP 15 is operating, that is, the pressure is reduced (vacuum exhaust) by the exhaust line in the chamber 10, and the valves V1- V3 is all closed (V1 CLOSE, V2 CLOSE, V3 CLOSE).

First, the pusher pin 30 housed in the susceptor 11 (PIN DOWN) separates the wafer W from the susceptor 11 and lifts it upwards (PIN UP). At this time, the height at which the pusher pin 30 lifts the wafer W from the susceptor 11 is not particularly limited, but preferably 10 to 20 mm. As a result, a space S is formed between the upper surface of the susceptor 11 and the rear surface of the wafer W. FIG.

Next, at the same time as the APC 14 is closed (APC CLOSE), the valve V2 of the exhaust pipe 17 and V3 of the heat conductive gas supply pipe 29 are opened (V2 OPEN, V3 OPEN), and the heat conductive gas supply hole 27 is opened. The N ₂ gas is blown into the space S toward the rear surface of the lifted wafer W, and the rough exhaust line discharges the N ₂ gas blown into the space S together with the gas remaining in the chamber 10 out of the chamber 10. Thereby, the viscous flow with a large gas viscous force generate | occur | produces toward the outer peripheral part of the susceptor 11 from the back surface of the wafer W in space S is generated. At this time, if the inside of the chamfer 10 is more than a predetermined pressure, viscous flow tends to occur. Therefore, in the rough exhaust line, the pressure in the chamber 10 does not fall below a predetermined pressure, for example, 133 Pa (1 Torr). Preferably, the N ₂ gas or the like in the chamber 10 is maintained such that the pressure in the chamber 10 is maintained in a predetermined pressure range, for example, in the range of 1.33 × 10 ^{3 to} 1.33 × 10 ⁴ Pa (10 to 100 Torr). To discharge. As a result, viscous flow can be reliably generated in the space S. The viscous flow causes the particles detached from the backside of the wafer W to be described later to be rolled up and discharged from the chamber 10 together with the gas in the chamber 10.

Subsequently, the DC power supply 22 alternately applies high voltages having different polarities, for example, voltages of + 500V and -500V to the electrode plate 20 (HV +500, HV -500). At this time, due to the application of a high voltage to the electrode plate 20, an electrostatic field is generated in the chamber 10, particularly in the space S, and an electrostatic stress, for example, Maxwell stress on the backside of the wafer W. This works. As a result, the adhesion of the particles attached to the back surface of the wafer W is weakened, and the particles are detached. The detached particles are discharged out of the chamber 10 from the space S by the aforementioned viscous flow. The electrostatic stress acts effectively on the back side of the wafer W when the high voltage is applied to the electrode plate 20 and when it is stopped. Here, in the plasma processing apparatus 1, since high voltage is repeatedly applied to the electrode plate 20, an effective electrostatic stress acts repeatedly on the back surface of the wafer W. As shown in FIG. Therefore, the particle | grains adhering to the back surface of the wafer W can be removed more fully.

The absolute value of the voltage alternately applied to the electrode plate 20 is preferably large, for example, 500 V or more, preferably 2 kV or more. Thereby, the electrostatic stress which acts on the back surface of the wafer W can be enlarged, and desorption of a foreign material can be performed reliably.

In addition, when the high voltage of the same polarity is repeatedly applied to the electrode plate 20, the electrode plate 20 is charged (charged up), and as a result, the electrostatic stress acting on the back surface of the wafer W is reduced, The removal efficiency of the particle adhering to the back surface of the wafer W may fall. In the plasma processing apparatus 1, since high voltages having different polarities are alternately applied to the electrode plate 20, the electrode plate 20 is not charged, and the removal efficiency of particles attached to the back surface of the wafer W is lowered. Can be prevented.

As described above, the effective action of the electrostatic stress is related to the number of times of applying the high voltage to the electrode plate 20 and not to the time of applying the high voltage to the electrode plate 20. Therefore, the application time of the high voltage to the electrode plate 20 may be 1 second or less, for example.

While alternately applying high voltages with different polarities to the electrode plate 20 described above, the valve V1 of the processing gas introduction pipe 38 is opened (V1 OPEN), and is inert instead of the processing gas from the shower head 33. Gas, for example N ₂ gas, is introduced into the chamber 10. At this time, since the chamber 10 is depressurized by a rough exhaust line, a sudden pressure rise occurs immediately below the shower head 33, whereby the introduced N ₂ gas generates a traveling shock wave, The generated traveling shock wave reaches the lifted wafer W. As a result, an impact force is applied to the wafer W, and particles adhering to the back surface of the wafer W are detached. At this time, the detached particles are discharged out of the chamber 10 from the space S by the aforementioned viscous flow.

Further, in the plasma processing apparatus (1), N ₂ gas is also the valve V1 in the shower head 33, the process gas supply pipe (38) to execute immediately the pressure rises under effectively in the chamber 10 of the entrance Further downstream, it is preferred that no orifice structure, such as a flow control device (massflow controller) or a slow up valve, is disposed.

After the valve V1 of the process gas introduction pipe 38 is opened (V1 OPEN), after alternating high voltages having different polarities to the electrode plate 20 is performed a predetermined number of times, for example, four times in the drawing, The valve V1 of the process gas introduction pipe 38 is closed (V1 CLOSE), the APC 14 is opened (APC OPEN), and the valve V2 of the exhaust pipe 17 and V3 of the heat conductive gas supply pipe 29 are closed (V2). CLOSE, V3 CLOSE), this processing ends.

The wafer W subjected to the above-described substrate cleaning process is carried out from the chamber 10 via the carrying in and out ports 31 and brought into the transfer chamber, for example, the load lock chamber, but the particles attached to the back surface of the wafer W are sufficiently removed. As a result, the load lock chamber is not contaminated by particles.

According to the above-described substrate cleaning method, when the space S is generated between the susceptor 11 and the wafer W, high voltages having different polarities are alternately applied to the electrode plate 20, so that the electrostatic discharge is performed in the space S. When a field is generated and an electrostatic stress acts on the back side of the wafer W, and the space S is generated and the pressure in the chamber 10 is reduced by the rough exhaust line, N ₂ gas is introduced into the chamber 10. The traveling shock wave is generated in the chamber 10, and the impact force is applied to the wafer W by the generated traveling shock wave. As a result, the particles attached to the back surface of the wafer W are detached into the space S. Therefore, desorption of particles does not require sputtering by plasma ions or chemical reaction by radicals, so that the wafer W is not damaged.

In addition, when the said space S occurs, the N ₂ gas is ejected from the heat transfer gas supply holes 27 to the space S, the N ₂ gas ejected in the space S is roughly taken out from the chamber 10 by the exhaust line Therefore, viscous flow of N ₂ gas occurs in the space S. The detached particle is rolled up in the above-mentioned viscous flow and discharged out of the chamber 10 from the space S.

Therefore, the particles adhering to the back surface of the wafer W can be sufficiently removed without damaging the wafer W. FIG.

In the above-described plasma processing apparatus 1, the N ₂ gas or the like in the chamber 10 is discharged by the rough exhaust line so that the pressure in the chamber 10 does not fall below a predetermined pressure. By reducing the open width of 14), the N ₂ gas or the like in the chamber 10 may be discharged by the present exhaust line so that the pressure in the chamber 10 does not fall below a predetermined pressure. Can cause flow.

Further, the present invention is applicable not only to the plasma processing apparatus configured as the etching processing apparatus, but also to other plasma processing apparatuses, for example, the plasma processing apparatus configured as the CVD apparatus or the ashing apparatus.

Next, the plasma processing apparatus as the substrate cleaning apparatus according to the second embodiment of the present invention will be described in detail.

The plasma processing apparatus as the substrate cleaning apparatus according to the second embodiment has the same configuration and operation as those of the first embodiment described above. Therefore, the overlapping configuration and operation will not be described. Explain the action.

In the plasma processing apparatus as the substrate cleaning apparatus according to the second embodiment, as in the first embodiment, the wafer W is separated from the upper surface of the susceptor 11 by the pusher pin 40 to be described later. At this time, an electrostatic field is generated to exert an electrostatic stress on the backside of the wafer W, but the electrostatic field is not caused by the application of the high voltage to the electrode plate 20, but is applied to the application of the high voltage to the wafer W by the pusher pin 40. It differs from 1st Embodiment in the point which originates.

3 is a diagram showing a schematic configuration of a pusher pin in the plasma processing apparatus as the substrate cleaning apparatus according to the second embodiment.

In Fig. 3, the pusher pin 40 is a rod-shaped body made of a conductor, and one end is formed into a hemispherical shape as long as it is in contact with the back surface of the wafer W, and the other end thereof is electrically connected to the DC power supply 41. have. In addition, the surface of the pusher pin 40 is preferably covered with a dielectric or the like in order to prevent discharge from the surface. However, the surface of one end of the hemispherical shape is conductive to apply a high voltage to the wafer W. The body is exposed. The pusher pin 40 is moved up and down in the drawing by rotating the motor (not shown) into a linear motion by a ball screw or the like.

Moreover, the some pusher pin 40 is arrange | positioned in the part in which the wafer W is adsorb | sucked on the upper surface of the susceptor 11. As shown in FIG. Then, the pusher pin 40 protrudes from the upper surface of the susceptor 11 to separate the wafer W from the susceptor 11 and lift upwards. At this time, as in the first embodiment, a space S is formed between the upper surface of the susceptor 11 and the rear surface of the wafer W. As shown in FIG.

In the plasma processing apparatus as the substrate cleaning apparatus according to the second embodiment, after etching the wafer W, the wafer W is separated from the upper surface of the susceptor 11 by the pusher pin 40 to generate a space S. At this time, a high voltage is applied to the wafer W from the DC power supply 41 via the pusher pin 40, N ₂ gas or the like is supplied to the space S from the heat conduction gas supply hole 27, and the chamber 10 is roughly exhausted. Is exhausted by. In addition, process gas is introduced into the chamber 10 from the shower head 33 while the chamber 10 is being decompressed by the rough exhaust line.

In the base cleaning method performed in the plasma processing apparatus as the base cleaning apparatus according to the second embodiment, instead of alternately applying high voltages having different polarities to the electrode plate 20, the pusher pins 40 are applied to the wafer W. Although different from the first embodiment in that high voltages having different polarities are alternately applied, an electrostatic field is generated in the space S, and an electrostatic stress acts on the back side of the wafer W, and particles adhered to the back side of the wafer W. The adhesive force of is weakened, and the particle detach | desorbs is the same as that of 1st Embodiment.

In addition, it is preferable that the high voltage applied to the wafer W via the pusher pin 40 is, for example, 500 V or more, preferably 2 kV or more, and the application time of the high voltage may be 1 second or less, for example. Is the same as

According to the above-described substrate cleaning method, when a space S is generated between the susceptor 11 and the wafer W, high voltages having different polarities are alternately applied to the wafer W via the pusher pins 40. In the space S, when an electrostatic field is generated and an electrostatic stress acts on the back surface of the wafer W, and the space S is generated and the inside of the chamber 10 to the rough exhaust line is depressurized, the N ₂ gas is supplied to the chamber 10. Since is introduced, the traveling shock wave is generated in the chamber 10, and the impact force is applied to the wafer W by the generated traveling shock wave. As a result, the particles attached to the back surface of the wafer W are detached into the space S. Therefore, desorption of particles does not require sputtering with plasma ions or chemical reactions with radicals, so that the wafer W is not damaged.

In addition, when the said space S occurs, the N ₂ gas is ejected from the heat transfer gas supply holes 27 to the space S, the N ₂ gas ejected in the space S is rough due to the exhaust line taken out from the chamber 10 Therefore, viscous flow of N ₂ gas occurs in the space S. The detached particles are discharged out of the chamber 10 from the space S by being caught in the aforementioned viscous flow.

Therefore, the particles adhering to the back surface of the wafer W can be sufficiently removed without damaging the wafer W. FIG.

Next, the substrate cleaning apparatus according to the third embodiment of the present invention will be described in detail.

The substrate processing apparatus according to the third embodiment differs from the above-described first and second embodiments in that only the back surface of the wafer W is cleaned without performing plasma processing on the wafer W. FIG.

4 is a cross-sectional view showing a schematic configuration of a substrate cleaning device according to a third embodiment of the present invention.

In FIG. 4, the substrate cleaning device 42 has a box-shaped chamber 43 made of metal, for example, aluminum or stainless steel, and has a column-shaped stage 44 in which the wafer W is mounted in the chamber 43. ) Is arranged.

Between the side wall of the chamber 43 and the stage 44, an exhaust passage 65 is formed that functions as a flow path for discharging gas above the stage 44 out of the chamber 43. This exhaust passage 65 is connected to a rough exhaust line. The rough exhaust line includes an exhaust pipe 45 having a diameter of, for example, 25 mm and a valve V5 disposed in the middle of the exhaust pipe 45 for communicating the exhaust path 65 with the DP 46 serving as the exhaust pump. This valve V5 can block the exhaust passage 65 and the DP 46. The rough exhaust line exhausts gas in chamber 43 by DP 46.

In the upper part of the stage 44, a disk-shaped electrode plate 47 made of a conductive film for adsorbing the wafer W by electrostatic attraction is disposed, and a DC power source 48 is electrically connected to the electrode plate 47. It is. The wafer W is sucked and held on the upper surface of the stage 44 by a Coulomb force generated by a DC voltage applied from the DC power supply 48 to the electrode plate 47.

A plurality of gas supply holes 49 are opened in the portion where the wafer W is adsorbed on the upper surface of the stage 44. These gas supply holes 49 communicate with the gas supply line 64 which has the valve V6 via the gas supply line 50 arrange | positioned inside the stage 44, and are connected to the gas supply line 64 first. Gas from a gas supply unit (not shown), for example, N ₂ gas, is supplied to a gap between the upper surface of the stage 44 and the rear surface of the wafer W. Moreover, the valve V6 can block the gas supply hole 49 and the 1st gas supply part.

Moreover, the some pin 51 which protrudes from the upper surface of the stage 44 is arrange | positioned in the part which the wafer W adsorb | sucks on the upper surface of the stage 44. The pin 51 lifts the wafer W carried in the chamber 43 and separates it from the stage 44. At this time, a space S is formed between the upper surface of the stage 44 and the rear surface of the wafer W. FIG. These pins 51 may move in the up and down direction in the figure similarly to the pusher pins 30.

The side wall of the chamber 43 is provided with the gate valve 53 which opens and closes the carrying-in / out port 52 of the wafer W. As shown in FIG. In addition, a gas introduction pipe 54 for introducing gas, for example, N ₂ gas, into the chamber 43 from the second gas supply part (not shown) is connected to the ceiling of the chamber 43. The valve V4 is arranged in the middle of the gas introduction pipe 54. The valve V4 can block the inside of the chamber 43 and the second gas supply part.

The substrate cleaning device 42 is, for example, disposed in a parallel substrate processing system and attached to the back side of the wafer W subjected to plasma processing by a plasma processing apparatus 56 described later included in the substrate processing system. Remove one foreign object.

FIG. 5 is a diagram illustrating a schematic configuration of a substrate processing system in which the substrate processing apparatus of FIG. 4 is disposed.

In FIG. 5, the substrate processing system 55 is a plasma processing apparatus 56 for etching a wafer W and a transfer arm 57 of a link-type single pick type that sends and receives wafers W to and from the plasma processing apparatus 56. ), A load ship 60 for accommodating a carrier box for storing a wafer W for one lot, an orienter for pre-arranged the wafer W 61, a substrate cleaning device 42 described above, and a loader module 63 for arranging a scalar dual arm type transfer arm 62 as a rectangular common conveyance path. The process ship 59, the rod boat 60, the orienter 61, and the board cleaning device 42 are connected to the loader module 63 so as to be mounted and detached therefrom, but the board cleaning device 42 is connected to the loader module ( It is disposed at one end in the longitudinal direction of the loader module 63 so as to face the orienter 61 via 63.

In the substrate processing system 55, the wafer W subjected to plasma treatment in the plasma processing apparatus 56 is a carrier arm 62 in the load lock chamber 58 and a carrier arm 62 in the loader module 63. Is loaded into the substrate cleaning device 42. The substrate cleaning device 42 removes particles adhering to the back surface of the wafer W by performing a substrate cleaning method described later.

Hereinafter, the substrate cleaning method performed in the substrate cleaning device 42 will be described.

The precondition for performing this substrate cleaning method is that the wafer W is subjected to an etching process and is mounted on the upper surface of the stage 44. No voltage is applied to the electrode plate 47, and the valves V4 to V6 All are closed.

First, the wafer W carried into the chamber 43 is mounted on the pin 51 which protrudes from the upper surface of the stage 44. At this time, the height that the pin 51 lifts the wafer W from the stage 44 is preferably 10 to 20 mm, similarly to the first embodiment. As a result, a space S is formed between the upper surface of the stage 44 and the rear surface of the wafer W. FIG.

Subsequently, the gate valve 53 is closed, and the valve V5 of the exhaust pipe 45 and the valve V6 of the gas supply pipe 64 open to the space S toward the rear surface of the wafer W on which the gas supply hole 49 is lifted. The N ₂ gas is ejected, and the rough exhaust line ejects the N ₂ gas ejected into the space S out of the chamber 43. As a result, there arises a viscous flow or the N ₂ gas flowing toward the outer peripheral part of the stage 44 from the back side of the wafer W in the space S. At this time, similarly to the first embodiment, the rough exhaust line preferably discharges the N ₂ gas or the like in the chamber 43 so that the pressure in the chamber 43 does not fall below a predetermined pressure. The viscous flow is discharged from the chamber 43 by causing the particles detached from the back surface of the wafer W to be described later to be rolled up.

Next, the DC power supply 48 alternately applies high voltages having different polarities to the electrode plate 47. At this time, an electrostatic field is generated in the space S, an electrostatic stress acts on the back surface of the wafer W, the adhesion force of the particles adhered to the back surface of the wafer W is weakened, and the particles are detached from the first embodiment. The same is true. The detached particles are discharged out of the chamber 43 in the space S by the above-described viscous flow.

In addition, it is the same as that of 1st Embodiment that the high voltage applied to the electrode plate 47 is 500 V or more, for example, preferably 2 kV or more, and that the application time of a high voltage may be 1 second or less, for example.

While alternately applying high voltages having different polarities to the wafer W described above, the valve V4 of the gas introduction pipe 54 is opened, and the N ₂ gas is introduced into the chamber 43 from the gas introduction pipe 54. At this time, since the pressure in the chamber 43 is reduced by the rough exhaust line, a sudden pressure rise occurs immediately below the ceiling of the chamber 43, and the introduced N ₂ gas generates a traveling shock wave, and the generated travel is generated. The impact force is applied to the wafer W by the shock wave, and the particles adhering to the back surface of the wafer W are detached as in the first embodiment. At this time, the detached particles are discharged out of the chamber 43 from the space S by the aforementioned viscous flow. In the substrate cleaning device 42, it is preferable that the orifice structure is not disposed downstream of the valve V4 in the gas introduction pipe 54 as in the first embodiment.

Then, in a state where the valve V4 of the gas introduction pipe 54 is opened, after a predetermined number of times of alternating application of a high voltage having a different polarity to the wafer W is performed, the valve V4 of the gas introduction pipe 54 and the valve V5 of the exhaust pipe 45 are And the valve V6 of the gas supply line 64 closes, and this process is complete | finished. The wafer W subjected to the above-described substrate cleaning process is carried out from the chamber 43 via the carrying in and out ports 52 and carried into the loader module 63 or the load boat 60, but is attached to the back surface of the wafer W. Since the particles are sufficiently removed, the loader module 63 and the rod boat 60 are not contaminated by the particles.

According to the above-described substrate cleaning method, when the space S is formed between the stage 44 and the wafer W, high voltages having different polarities are alternately applied to the wafer W, so that an electrostatic field is generated in the space S and the wafer W is generated. An electrostatic stress acts on the back side of the chamber, and when the space S is generated and the pressure in the chamber 43 is reduced by the rough exhaust line, the N ₂ gas is introduced into the chamber 43, so that the chamber 43 The traveling shock wave is generated in the interior, and the impact force is applied to the wafer W by the generated traveling shock wave. Thereby, the particle | grains adhering to the back surface of the wafer W detach | desorb into space S. Therefore, since plasma is not required for particle detachment, the wafer W is not damaged.

Further, to the space S that when the generation, and the N ₂ gas ejected from the gas supply hole 49 to the space S, the N ₂ gas ejected in the space S is roughly taken out from the chamber 43 by the exhaust line Therefore, a viscous flow of N ₂ gas occurs in the space S. The detached particle is rolled up in the above-mentioned viscous flow and discharged out of the chamber 43 from the space S.

Therefore, the particles adhering to the back surface of the wafer W can be sufficiently removed without damaging the wafer W. FIG.

In the above-described substrate cleaner 42, the substrate cleaner 42 has its own DPL 46, but the substrate cleaner 42 and the plasma processing apparatus 56 may share the DP. The structure of the substrate processing system 55 can be simplified.

In the above-described embodiment, the case where the plasma processing apparatus functions as the substrate cleaning apparatus or the case where the exclusive substrate cleaning apparatus is provided has been described, but another apparatus constituting the substrate processing system is the substrate cleaning apparatus according to the present invention. It may function as.

For example, when a load locker functions as the substrate processing apparatus which concerns on this invention, the said load locker is a conveyance arm, the exhaust apparatus which exhausts the inside of a load locker, and the gas which introduces gas into a load locker. It is preferable that an introduction device is provided, and the carrier arm has an electrode for generating an electrostatic field between the pin projecting from the wafer mounting surface, the wafer W, and the wafer mounting surface, and a gas injection value for blowing gas toward the rear surface. In this load locker, when the wafer W is lifted from the wafer mounting surface by a pin and a space S is generated, a high voltage is applied to the electrode, a gas is injected toward the back surface of the wafer W, and the load locker is exhausted. Exhausted by the device. In addition, while the inside of the load locker is depressurized by the exhaust device, gas is introduced into the load locker from the gas introduction device.

(Example)

Next, examples of the present invention will be described in detail.

The following embodiments were executed in the above-described plasma processing apparatus 1.

First, a wafer W having a large amount of particles attached to the back surface was prepared, and the wafer W was mounted on the pusher pin 30 protruding from the susceptor 11 in the chamber 10.

After depressurizing the inside of the chamber 10 by the exhaust line, the APC 14 is closed, and the valve V2 of the exhaust pipe 17 and V3 of the heat conductive gas supply pipe 29 are opened to open the chamber 10. Slowly exhausting the inside, N ₂ gas was blown out from the heat conduction gas supply hole 27 toward the back surface of the wafer W. As shown in FIG. As a result, viscous flow was generated in the space S while maintaining the inside of the chamber 10 at 6.65 × 10 ³ Pa (5OTorr) or more.

Subsequently, valve V1 was opened and N ₂ gas was introduced into chamber 10 at a flow rate of 7.0 × 10 ⁴ SCCM. While valve V1 was open, alternating application of voltages of + 2kV and -2kV to electrode plate 20 was repeated six times, after which valve V1 was closed. Further, the valve V1 is opened again and N ₂ gas is introduced into the chamber 10 at a flow rate of 7.0 × 10 ⁴ SCCM, and while the valve V1 is open, alternating voltages of +2 kV and -2 kV to the electrode plate 20 is performed. The test was repeated five times, after which the valve V1 was closed. At this time, the laser beam was irradiated to space S, and the scattered light which originates in a particle | grain was observed by image | photographing with a CCD camera. The shape of the photographed scattered light is shown in Figs. 6A to 6C.

FIG. 6: A is a figure which shows typically the shape of space S when the application of the voltage of + 2kV and -2kV to the electrode plate 20 is repeated while the valve V1 is open. Here, a large amount of particles are detached from the back surface of the wafer W due to the electrostatic stress generated by alternating application of the propagation shock wave and the voltage generated by the introduced N ₂ gas, and the detached particles form a group L. This was observed.

FIG. 6B is a diagram schematically showing the shape of the space S after a few seconds have elapsed from FIG. 6A. Here, a state in which one group L of particles is excluded from the space S by viscous flow flowing from the back surface of the wafer W toward the outer peripheral portion of the susceptor 11 in the space S is observed.

FIG. 6C is a diagram schematically showing the shape of the space S after several seconds have passed from FIG. 6B. Here, the shape in which one group L of particles was completely excluded from the space S was observed.

The graph which summarized these observation results is shown in FIG.

In FIG. 7, the horizontal axis represents time, and the vertical axis represents the number of particles, voltage value, and pressure value. In addition, V _E represents the voltage applied to the electrode plate 20, V _W represents the voltage induced in the wafer W by V _E , and P represents the pressure in the chamber 10. In particular, each point protruded in the figure represents the number of particles observed at each observation time. The portion where the value of P is constant is the portion where the pressure in the chamber 10 exceeds the measurable range.

From Fig. 7, a large amount of particles are detached from the back surface of the wafer W by the traveling shock wave generated immediately after the valve V1 is opened and a large amount of N ₂ gas is introduced into the chamber 10, and the voltage to the electrode plate 20 is further reduced. It was found that the particles were further detached by repeated alternating applications. It was found that the particles adhering to the back surface of the wafer W can be sufficiently desorbed by the repetitive introduction of a large amount of N ₂ gas into the chamber 10 and alternating application of the voltage. Further, since a large amount of particles are released into the chamber 10 of the _second N ₂ gas and alternating particles are repeatedly reduced, the large amount of N ₂ gas is introduced into the chamber 10. It was found that by repeatedly performing alternating application of the above voltages, particles can be effectively detached.

At the same time, the particles discharged from the inside of the chamber 10 via the rough exhaust line were observed by a particle monitor using a laser scattering method arranged in the middle of the rough exhaust line, and the same observation result as in FIG. 7 was obtained. As a result, it was found that the particles from which the viscous streams detached were effectively discharged from the chamber 10.

According to the substrate cleaning apparatus according to claim 1, when a space is generated between the mounting table and the substrate, a voltage is applied to the electrode disposed on the mounting table. Stress acts. As a result, the foreign matter attached to the back side of the substrate is separated. In addition, when the space is generated, gas is supplied to the space, and the inside of the storage chamber is exhausted, so that a gas flow occurs in the space, and foreign matter separated by the gas flow is removed from the space. And exhaust from the storage chamber. Therefore, the substrate cleaning apparatus can sufficiently remove the foreign matter adhering to the back side of the substrate without damaging the substrate.

According to the substrate cleaning apparatus according to claim 2, since the gas is introduced into the storage chamber when the inside of the storage chamber is depressurized, a traveling shock wave is generated in the storage chamber, and the foreign matter adhering to the back of the substrate by the shock wave enters the space. Break away. Therefore, the foreign matter adhering to the back side of the board | substrate can be removed efficiently, without damaging a board | substrate.

According to the substrate cleaning apparatus of claim 3, since the voltage is discontinuously applied to the electrode, the application of the voltage to the electrode is repeated. Accordingly, the electrostatic stress repeatedly acts on the back side of the substrate. Therefore, the foreign material adhering to the back surface of a board | substrate can be removed more fully.

According to the substrate cleaning apparatus of claim 4, since voltages having different polarities are alternately applied, charging of the substrate can be prevented. When the substrate is charged, the electrostatic stress acting on the back side of the substrate by the application of voltage is reduced. Therefore, by preventing the charging of the substrate, it is possible to prevent the removal efficiency of the foreign matter adhering to the back surface of the substrate to decrease.

According to the substrate cleaning apparatus of claim 5, since the voltage applied to the electrode when the space is generated is 500 V or more, the electrostatic stress acting on the back side of the substrate can be increased, and desorption of foreign matter can be reliably performed. .

According to the substrate cleaning apparatus of claim 6, the voltage is 2 kV or more, so that the electrostatic stress can be increased.

According to the substrate cleaning device according to claim 7, the exhaust device maintains the pressure in the storage chamber at 133 Pa or more, so that a viscous flow having a large gas viscous force can be generated in the space. The foreign material detached from the back side of the substrate is caught in viscous flow and exhausted from the storage chamber together with the gas in the storage chamber. Therefore, the foreign matter adhering to the back side of the board | substrate can be removed reliably.

According to the board | substrate cleaning apparatus of Claim 8, since the exhaust apparatus keeps the pressure in a storage chamber in the range of 1.33x10 <^3> -1.33 * 10 <^4> Pa, viscous flow can be reliably produced in space.

According to the substrate cleaning apparatus according to claim 9, when the space is generated between the mounting table and the substrate, the separation device applies a voltage to the substrate, so that an electrostatic field is generated in the space, so that an electrostatic stress is generated on the back surface of the substrate. Works. Thereby, the foreign material adhering to the back surface of a board | substrate detach | desorbs. In addition, when the space is generated and the inside of the storage chamber is depressurized, since the gas introduction unit introduces gas into the storage chamber, a traveling shock wave is generated in the storage chamber, and the foreign matter adhering to the backside of the substrate by the shock wave is released into the space. Tally. In addition, when the space is generated, gas is supplied to the space and the inside of the storage chamber is exhausted, so that a gas flow is generated in the space, and foreign substances desorbed by the gas flow are removed from the space, and further into the storage chamber. From the exhaust. Therefore, the substrate cleaning apparatus can sufficiently remove the foreign matter adhering to the back side of the substrate without damaging the substrate.

According to the substrate cleaning method according to claim 10, when a space is generated between the mounting table and the substrate, a voltage is applied to the electrode disposed on the mounting table. Stress acts. Thereby, the foreign material adhering to the back surface of a board | substrate detach | desorbs. In addition, when the space is generated, gas is supplied to the space and the inside of the storage chamber is exhausted, so that a gas flow is generated in the space, and foreign substances desorbed by the gas flow are removed from the space, and further into the storage chamber. From the exhaust. Therefore, the foreign material adhering to the back surface of a board | substrate can fully be removed, without damaging a board | substrate.

According to the substrate cleaning method according to claim 11, since the gas is introduced into the storage chamber when the space is generated and the interior of the storage chamber is depressurized, a traveling shock wave is generated in the storage chamber, and the back of the substrate is affected by the shock wave. Foreign matter attached to the surface detaches into space. Therefore, the foreign matter adhering to the back side of the board | substrate can be removed efficiently, without damaging a board | substrate.

According to the substrate cleaning method of Claim 12, since voltage is discontinuously applied to an electrode, application of the voltage to an electrode is repeated. Accordingly, the electrostatic stress acts repeatedly on the back side of the substrate. Therefore, the foreign material adhering to the back surface of a board | substrate can be removed more fully.

According to the substrate cleaning method of claim 13, since voltages having different polarities are alternately applied, charging of the substrate can be prevented. When the substrate is charged, the electrostatic stress acting on the back side of the substrate by the application of voltage is reduced. Therefore, by preventing the charging of the substrate, it is possible to prevent the removal efficiency of the foreign matter adhering to the back surface of the substrate to decrease.

According to the substrate cleaning method according to claim 14, since a voltage is applied to the substrate when a space is generated between the mounting table and the substrate, an electrostatic field is generated in the space, and an electrostatic stress acts on the back surface of the substrate. Thereby, the foreign material adhering to the back surface of a board | substrate detach | desorbs. In addition, when a space is generated and the inside of the storage chamber is depressurized, gas is introduced into the storage chamber, so that a traveling shock wave is generated in the storage chamber, and the foreign matter adhering to the back side of the substrate is released into the space by the shock wave. . In addition, when the space is generated, gas is supplied to the space, and the inside of the storage chamber is exhausted, so that a gas flow is generated in the space, and foreign substances desorbed by the gas flow are removed from the space, and further into the storage chamber. From the exhaust. Therefore, the foreign material adhering to the back surface of a board | substrate can fully be removed, without damaging a board | substrate.

Claims (14)

A storage chamber accommodating the substrate, A mounting table disposed in the storage chamber and configured to mount the substrate; An electrode disposed on the mounting table and having a voltage applied thereto to adsorb the substrate to the mounting table; An exhaust device for exhausting the inside of the storage chamber, A separation device which spaces the mounting table and the substrate to create a space between the mounting table and the substrate; A gas supply device for supplying gas to the space, When the space is generated, a voltage is applied to the electrode, the gas supply device supplies gas to the space, and the exhaust device exhausts the inside of the storage chamber. The method of claim 1, And a gas introduction portion for introducing gas into the storage chamber when the inside of the storage chamber is depressurized and the space is generated. The method according to claim 1 or 2, And a voltage is applied discontinuously to the electrode. The method of claim 3, wherein Substrate cleaning device, characterized in that the voltage of different polarity is alternately applied to the electrode. The method of claim 4, wherein The absolute value of the voltage is 500V or more substrate cleaning apparatus. The method of claim 5, And an absolute value of the voltage is 2 kV or more. The method according to claim 1 or 2, And the exhaust device maintains the pressure in the storage chamber in the range of 1.33 × 10 ² to 1.33 × 10 ⁴ Pa when the space is generated. The method of claim 7, wherein And the exhaust device maintains the pressure in the storage chamber in the range of 1.33 × 10 ³ to 1.33 × 10 ⁴ Pa when the space is generated. A storage chamber accommodating the substrate, A mounting table disposed in the storage chamber and configured to mount the substrate; An exhaust device for exhausting the inside of the storage chamber, A separation device that spaces the mounting table and the substrate to create a space between the mounting table and the substrate and contacts the substrate to apply a voltage to the substrate; A gas supply device for supplying gas to the space; A gas introduction part for introducing gas into the storage chamber, When the space is generated, a voltage is applied to the substrate, the gas supply device supplies gas to the space, the exhaust device exhausts the inside of the storage chamber, and the inside of the storage chamber is depressurized and the And the gas introduction portion introduces gas into the storage chamber when space is generated. In the substrate cleaning method for removing foreign matter attached to the back of the substrate, An accommodating step of accommodating the substrate in the accommodating chamber A mounting step of mounting the substrate on a mounting table disposed in the accommodation chamber; A separation step of separating the mounting table and the substrate so that a space is generated between the mounting table and the substrate; A voltage application step of applying a voltage to an electrode disposed on the mounting table when the space is generated; A gas supply step of supplying gas to the space when the space is generated, And an exhausting step of exhausting the inside of the storage chamber when the space is generated. The method of claim 10, And a gas introduction step of introducing gas into the storage chamber when the inside of the storage chamber is depressurized and the space is generated. The method of claim 10 or 11, And in the voltage application step, applying a voltage discontinuously to the electrode. The method of claim 12, In the voltage applying step, substrate cleaning method, characterized in that for alternately applying a voltage having a different polarity to the electrode. In the substrate cleaning method for removing foreign matter attached to the back of the substrate, An accommodating step of accommodating the substrate in the accommodating chamber A mounting step of mounting the substrate on a mounting table disposed in the accommodation chamber; A separation step of separating the mounting table and the substrate so that a space is generated between the mounting table and the substrate; Applying a voltage to the substrate when the space is occurring; A gas supply step of supplying gas to the space when the space is generated, An exhausting step of exhausting the inside of the storage chamber when the space is generated; And a gas introduction step of introducing gas into the storage chamber when the inside of the storage chamber is depressurized and the space is generated.

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