JP2002050600A - Substrate-processing method and substrate processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate-processing method and a substrate processor, which can safely perform a processing, with out producing watermarks or dissolution of resist. SOLUTION: A wafer W is immersed in pure water in a processing tank 61, and is rinsed and cleaned. Dichloromethane is supplied into the processing tank 61. A state, in which the wafer is immersed in pure water, is converted to a state where it is immersed in dichloromethane. Then, the wafer W is raised to a drying chamber 61, dichloromethane adhered to the surface of the water W is evaporated and hot N2 gas is discharged to the water W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a substrate processing method and a substrate processing apparatus for processing a substrate.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process, a semiconductor wafer (hereinafter, referred to as a "wafer") is washed with a predetermined chemical solution or a cleaning solution such as pure water to remove particles, organic contaminants, and metals adhering to the wafer surface. A cleaning device that removes contamination such as impurities is used. Among them, a wet type cleaning apparatus that performs a cleaning process by immersing a wafer in a cleaning tank filled with a cleaning liquid is widely used.

Such a cleaning apparatus performs a cleaning process using a chemical solution or a pure water mainly composed of an ammonia component, a hydrochloric acid component, a hydrofluoric acid component, etc., and finally performs a final rinsing process using the pure water.
It is configured to perform a drying process. Cleaning equipment includes
A final rinse cleaning device in which the final rinse process is performed;
A drying device for performing the drying process.

[0004] For example, an IPA vapor drying method is adopted as a drying device. According to the IPA vapor drying method, highly hydrophilic IPA is applied to a wafer stored in a drying tank.
[Isopropyl alcohol: (CH ₃ ) ₂ CHOH] vapor is supplied to remove water droplets adhering to the surface of the wafer by using the volatilization of IPA, thereby drying the wafer.

Here, the surface of the wafer is exposed to the atmosphere while the wafer is transferred from the final rinse cleaning device to the drying device. In such a case, water droplets adhering to the surface of the wafer are naturally dried, and there is a possibility that a watermark (water mark) may be generated. Further, since these final rinse cleaning device and drying device are arranged in a horizontal line in the cleaning device, a footprint is required.

Therefore, a rinsing / drying device configured to perform both a final rinsing process and a drying process is conventionally known from the viewpoint of reducing a watermark and saving a footprint. As such a rinsing / drying device, for example, IPA vapor is supplied when a wafer immersed in pure water of a cleaning tank is lifted from the tank, and the final Marangoni effect utilizing the difference in surface tension between water and IPA is used. An apparatus for drying a wafer after a rinsing process is known.

[0007]

However, according to the conventional drying apparatus or rinsing / drying apparatus using IPA, IPA has a property of dissolving the resist. For example, a resist film is formed on a surface of a wafer along a predetermined circuit pattern. IP for such a wafer
When the A vapor or the IPA liquid is supplied, the resist surface may be melted, and pattern collapse may occur. In a memory circuit or the like, when a dual gate formed to suppress a leak current has a structure in which a resist is locally deposited and patterned, the thickness of the dual gate changes when IPA vapor is supplied. . Therefore, the operation of the circuit may be adversely affected. Furthermore, since IPA contains an alcohol component, there is a risk of ignition. For this reason, high-level safety measures and equipment are required.

Further, in order to sufficiently exert the Marangoni effect, the wafer W must be relatively slowly pulled out of pure water, and it takes time to raise the wafer W. Further, the wafer guide is provided with a plurality of grooves for holding the peripheral portion of the wafer. Water droplets are also adhered to a groove or a portion over a small portion such as a peripheral portion of a wafer held in the groove. Unlike the exposed surface of the wafer, it is difficult to supply the IPA vapor to the peripheral portion of the wafer held in the groove, and it takes time to dry.

Accordingly, an object of the present invention is to provide a substrate processing method and a substrate processing apparatus capable of safely processing a substrate with a resist film without generating a watermark and without pattern collapse. .

[0010]

According to the present invention, there is provided a method for processing a substrate using at least a first processing liquid and a second processing liquid in a processing tank. Replacing the state in which the substrate is in contact with the first processing liquid with the state in which the substrate is in contact with the second processing liquid having a specific gravity different from that of the first processing liquid. To provide a substrate processing method.

According to this substrate processing method, for example, the substrate is brought into contact with the first processing liquid filled in the processing tank. Next, a second processing liquid having a specific gravity different from that of the first processing liquid is supplied into the processing tank. The state where the substrate is in contact with the first processing liquid is replaced with the state where the substrate is in contact with the second processing liquid. Therefore, the first processing liquid adhering to the surface of the substrate can be replaced with the second processing liquid in the liquid without bringing the first processing liquid into contact with an external atmosphere.

In this processing method, when the substrate is replaced with a state in which the substrate is brought into contact with the second processing liquid having a specific gravity different from that of the first processing liquid, the first processing liquid is removed from the processing tank. Is preferably drained.

For example, pure water is appropriately used for the first processing liquid, and a hydrophobic solvent is appropriately used for the second processing liquid. In this case, first, the substrate is immersed in the first processing liquid filled in the processing tank and brought into contact with the first processing liquid. Next, for example, when supplying a second processing liquid having a higher specific gravity than the first processing liquid into the processing tank, the supplied second processing liquid sinks to the bottom of the processing tank. On the other hand, the first processing liquid is gradually drained from the upper part of the processing tank, for example, in accordance with the supply of the second processing liquid, and the first processing liquid layer and the second processing liquid layer are formed in the processing tank. I do. While the second processing liquid is accumulated and thickens the second processing liquid layer, the first processing liquid is expelled from the processing tank to thin the first processing liquid layer. The liquid filled in the processing tank is replaced with a second processing liquid. The substrate is immersed in the second processing liquid and brought into contact with the second processing liquid. Therefore, for example, water droplets adhering to the surface of the substrate can be replaced with a solvent in the liquid without contacting the liquid with an external atmosphere.

Further, for example, when a second processing liquid having a specific gravity lower than that of the first processing liquid is supplied into the processing tank, the supplied second processing liquid floats above the processing tank. For example, the first processing liquid is gradually drained from the lower part of the processing tank in accordance with the supply of the second processing liquid, and the processing is performed in the same manner as the second processing liquid having a specific gravity heavier than the first processing liquid. The liquid filled in the tank is
Replace with the processing solution. The substrate is immersed in the second processing liquid and brought into contact with the second processing liquid. Therefore, for example, water droplets adhering to the surface of the substrate can be replaced with a solvent in the liquid without contacting the liquid with an external atmosphere. In each case, the substrate is stopped in the processing bath and immersed in the second processing solution. For example, the substrate is moved and passed through the second processing solution supplied to the processing bath. Thus, the state where the substrate is brought into contact with the first processing liquid may be replaced with the state where the substrate comes into contact with the second processing liquid.

[0015] A first processing liquid layer and a second processing liquid layer may be formed in the processing tank, and the substrate may be moved from the first processing liquid layer to the second processing layer. Also in this case, as in the case described above, the substrate is immersed in the first processing liquid filled in the processing tank and brought into contact with the first processing liquid. Then,
A second processing liquid having a specific gravity different from that of the first processing liquid is supplied into the processing tank, and the first processing liquid layer and the second processing liquid are sufficiently immersed in the processing tank. Form a layer. Thereafter, the substrate is moved to the second processing liquid layer and immersed therein. This also allows the water droplets adhering to the surface of the substrate to be replaced with the solvent in the liquid without contacting the atmosphere. Also, for example, the substrate is moved without being immersed in the second processing solution layer, and the second processing solution layer is formed in the processing tank.
By passing the substrate through the processing liquid layer, the state in which the substrate is brought into contact with the first processing liquid may be replaced with the state in which the substrate is brought into contact with the second processing liquid.

After replacing the substrate in a state where the substrate is brought into contact with the second processing liquid having a specific gravity different from that of the first processing liquid,
It is preferable that the substrate is lifted above the processing tank and the substrate is dried. As described above, when the first processing liquid is pure water and the second processing liquid is a solvent, according to this method, the substrate to which the solvent is attached is raised above the processing tank and the surface of the substrate is removed. And the solvent is evaporated from the substrate.
Therefore, for example, without generating a watermark,
The substrate can be dried. In addition, since a liquefied solvent is used, there is less danger and a high level of safety measures and equipment are required, compared to the conventional method of drying a substrate using a vapor of a flammable solvent (eg, IPA). It becomes unnecessary.

After replacing the substrate in a state where the substrate is brought into contact with the second processing liquid having a specific gravity different from that of the first processing liquid,
The processing tank may be drained to dry the substrate. According to this method, the processing tank is drained to expose the substrate,
The solvent is evaporated from the substrate in the processing bath. This also allows the substrate to be dried without, for example, generating a watermark.

Preferably, after separating the substrate from the second processing liquid, a gas is supplied to the substrate. That is,
As described above, the substrate is raised above the processing tank and the second
After the liquid is separated from the second processing liquid or after the inside of the processing tank is drained and separated from the second processing liquid, for example, an N ₂ (nitrogen) gas or a heated N ₂ gas is supplied to the substrate. that way,
Drying can be promoted.

It is preferable that the surroundings of the processing tank be an inert atmosphere. For example, if the heat of vaporization of the solvent is large, heat is taken from the substrate when the solvent evaporates, and the surface temperature of the substrate decreases. In such a case, for example, vapor in the atmosphere may condense and water droplets may adhere to the surface of the substrate. However,
For example, the periphery of the processing tank (including the upper part of the processing tank) is filled with, for example, an N ₂ atmosphere so that vapor is not contained in the atmosphere, thereby preventing water droplets from adhering during evaporation of the solvent.

Preferably, the substrate has a resist film formed on a surface thereof, and the second processing liquid has a property of not dissolving the resist film. that way,
A substrate with a resist film can be suitably processed.
Further, the second processing liquid may be nonflammable.
Then, safety can be achieved even if the solvent is vaporized. As a second processing solution satisfying such conditions,
For example, there are solvents such as HMDS (hexamethyldisilazane), dichloromethane, and HFE (hydrofluoroether).

Further, IPA (isopropyl alcohol) may be mixed with the second processing liquid. Further, the second processing liquid may be heated. As described above, by mixing IPA with the second processing liquid or heating the second processing liquid, the first processing liquid in contact with the substrate can be smoothly removed by the second processing liquid.
Can be substituted.

Further, according to the present invention, there is provided an apparatus for processing a substrate in a processing tank, wherein the holding means holds the substrate in the processing tank, and a first processing liquid is supplied into the processing tank. A first processing liquid supply means, and a second processing liquid supply means for supplying a second processing liquid having a specific gravity different from that of the first processing liquid into the processing tank. Provided is a substrate processing apparatus.

In this substrate processing apparatus, pure water or the like is used as the first processing liquid, and a hydrophobic solvent is used as the second processing liquid, for example. According to such a substrate processing apparatus, the substrate is held by the holding means and stored in the processing tank. The first processing liquid is supplied into the processing tank by the first processing liquid supply means, and the substrate is brought into contact with the first processing liquid. Next, a second processing liquid having a specific gravity different from that of the first processing liquid is supplied into the processing tank by the second processing liquid supply means, and the substrate is brought into contact with the first processing liquid from the second processing liquid. Is replaced with a state in which the substrate is brought into contact with the processing liquid. Therefore, this substrate processing apparatus can suitably carry out the substrate processing method described above. Further, for example, water droplets adhering to the peripheral portion of the substrate held by the holding means can be replaced with a solvent in the liquid without contacting with an external atmosphere.

In this substrate processing apparatus, a first processing liquid discharging means for discharging the first processing liquid from the processing tank and a second processing liquid discharging means for discharging the second processing liquid from the processing tank. 2
It is preferable to include a processing liquid drainage unit.

According to such a configuration, the liquid contact of the substrate is realized by immersing the substrate in the liquid. That is, the first processing liquid is filled in the processing tank, and the substrate is immersed in the first processing liquid. Next, a second processing liquid having a specific gravity heavier or lighter than the first processing liquid is supplied into the processing tank by the second processing liquid supply means, and the upper part of the processing tank is supplied by the first processing liquid drain means. Alternatively, drain the first processing liquid from the lower part,
The liquid filled in the processing tank is replaced with a second processing liquid. After being immersed in the second processing liquid, the second processing liquid is drained from the processing tank by the second processing liquid drain means to expose the substrate, and the solvent is evaporated from the substrate in the processing tank. Let it.

The holding means may be movable up and down between the inside of the processing tank and the upper part of the processing tank. According to such a configuration, the liquid contact of the substrate is also realized by moving the substrate in the liquid. That is, the liquid filled in the processing tank is
And the holding means raises the substrate above the processing tank, and at this time, the substrate is passed through the second processing liquid. After forming the first processing liquid layer and the second processing liquid layer in the processing tank, the substrate is raised above the processing tank,
At this time, the substrate is passed through the second processing layer. After forming the first processing liquid layer and the second processing liquid layer in the processing tank,
The holding means may be moved up and down, and the substrate may be immersed in the second treatment liquid layer. After the substrate is brought into contact with the second processing liquid,
The holding means is raised, and the substrate is taken out of the processing tank. The substrate is exposed, and the solvent is evaporated from the substrate. Further, since the solvent is also evaporated from the peripheral portion of the substrate held by the holding means, it is also possible to easily dry a portion over details.

A gas supply means for supplying a gas for promoting drying to the substrate may be provided. Further, it may have an IPA supply means for mixing IPA with the second processing liquid.
Further, a heating means for heating the second processing liquid may be provided.

[0028]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view of a cleaning apparatus 1 including a rinsing / drying apparatus 21 according to the first embodiment. The cleaning device 1 includes a carrier C
Loading of wafers W as substrates in units, cleaning of wafers W,
The apparatus is configured to consistently perform drying of the wafer W and unloading of the wafer W in units of the carrier C.

In the cleaning device 1, the loading / unloading section 2
Performs an operation from loading a carrier C containing 25 wafers W before cleaning and shifting the wafers W to cleaning. That is, the carrier C placed on the loading stage 5 is transported, for example, two by two to the loader 7 by the transfer device 6, and the loader 7 takes out the wafer W from the carrier C.

The cleaning / drying processing section 10 includes a loading / unloading section 2
Wafer chuck cleaning / drying device 11 for cleaning and drying the wafer chuck 36 of the transport device 30 for transporting the wafer W in order from the side, and each wafer for cleaning the wafer W using various chemicals and cleaning liquids such as pure water. Cleaning device 12-1
5. Wafer chuck cleaning / drying device 16 for cleaning and drying the wafer chuck 37 of the transfer device 32, wafer cleaning devices 17 to 19, and wafer chuck cleaning for cleaning and drying the wafer chucks 33a and 33a of the transfer device 33. -Drying device 20, and wafer cleaning device 12-
Rinsing for performing a final rinsing cleaning (rinsing process) and a drying process on the wafer W cleaned in 15, 17 to 19
A drying device 21 is arranged. Further, on the front side (the front side in FIG. 1) of the cleaning / drying processing section 10, the above-described transfer devices 30, 31, 32, and 33 are arranged.

According to the general cleaning process, chemical cleaning and
Wafer cleaning apparatus 1 so that rinsing and cleaning can be performed alternately.
2, 14, 17, and 19 will perform chemical cleaning (chemical processing).
And the wafer cleaning devices 13, 15, 18 are phosphorus
Cleaning is performed. As an example,
In the cleaning device 12, a cleaning liquid mainly containing a sulfuric acid component is used.
SPM (H₂SO₄/ H₂O₂Using S)
After the PM cleaning, the organic substances adhering to the surface of the wafer W
Remove impurities such as contaminants. In addition, wafer cleaning equipment
In the case of 14, for example, a cleaning liquid mainly containing an ammonia component is used.
A certain APM (NH ₄OH / H₂O₂/ H₂O mixture)
SC1 cleaning is performed by using
To remove impurities such as organic contaminants and particles
You. In the wafer cleaning device 17, a hydrochloric acid component is mainly used.
HPM (HCl / H₂O₂/ H₂O's
SC2 cleaning using the mixed solution), and the surface of the wafer W
To remove metal ions and the like adhering to. In addition, wafer
In the cleaning device 19, a cleaning liquid mainly containing a hydrofluoric acid component is used.
DHF (HF / H₂Cleaning with DHF mixture
To remove the oxide film and the like formed on the surface of the wafer W
I do. In addition, in the wafer cleaning devices 13, 15, and 18, the pure
The rinsing of the wafer W is performed using water.

The above arrangement and each wafer cleaning device 12
The combinations of １５15 and 17〜19 can be arbitrarily combined depending on the type of the cleaning process for the wafer W. For example, a certain cleaning device may be reduced, or conversely, a wafer cleaning device for cleaning the wafer W with another type of chemical solution may be added.

The loading / unloading section 50 includes the washing / drying processing section 10
After the 25 wafers W cleaned and dried in the above are loaded into the carrier C, they are unloaded in units of the carrier C. That is, the unloader 51
The carrier C containing the cleaned wafer W
Is transported to the unloading section 52 by a transfer device (not shown).

Next, the rinsing method according to the first embodiment will be described.
The configuration of the drying device 21 will be described. As shown in FIG. 2, the rinsing / drying device 21 includes a processing tank 60 for rinsing the wafer W, a drying chamber 61 provided above the processing tank 60, and for drying the wafer W, A wafer guide 62 is provided as holding means for holding the wafer W.

The processing tank 60 includes a box-shaped inner tank 63 and an outer tank 64 having a sufficient size to accommodate the wafer W. The processing tank 60 is provided with a pure water supply circuit 65 as first processing liquid supply means for supplying pure water (DIW) as a first processing liquid.

The inlet of the pure water supply circuit 65 is connected to a pure water supply source (not shown). An opening / closing valve 66 and a flow rate controller 67 are sequentially interposed in the pure water supply circuit 65, and the outlet of the pure water supply circuit 65 is connected to jet nozzles 68, 68 arranged in pairs below the inner tank 63. Have been.

A solvent supply circuit 70 is connected to the pure water supply circuit 65 as second processing liquid supply means for supplying a solvent as a second processing liquid. The inlet of the solvent supply circuit 70 is connected to a solvent supply source (not shown). The solvent supply circuit 70 includes an on-off valve 71 and a flow controller 72.
Are interposed sequentially.

Solvents having a specific gravity different from that of pure water and having a hydrophobic property include, for example, dichloromethane and HMDS.
(Hexamethyldisilazane) and the like are used. Although dichloromethane and HMDS have volatility, they do not contain flammable components such as alcohol, and are therefore safe to vaporize. These solvents have a property of not dissolving the resist film. For example, when a resist film is formed on the surface of the wafer W along a predetermined circuit pattern, even if such a wafer W is immersed in dichloromethane or HMDS, the resist surface is not dissolved, but the pattern collapses. Etc. do not occur.

At the bottom of the inner tank 63, a pure water drain pipe 81 is connected as a first treatment liquid drainage means via an on-off valve 80, and as a second treatment liquid drainage means via an on-off valve 82. A solvent drain pipe 83 is connected. In addition, the outer tank 64
The pure water drain pipe 84 is connected to the bottom of the solvent drain pipe 84 via a three-way valve 85.
6 are connected. Therefore, the pure water in the inner tank 63 is drained by the pure water drain pipe 81, the three-way valve 85 is switched to the pure water drain pipe 84 side, and the pure water in the outer tank is drained by the pure water drain pipe 84. It has become. Further, the solvent in the inner tank 63 is drained by the solvent drain pipe 83, the three-way valve 85 is switched to the solvent drain pipe 86 side, and the solvent in the outer tank 64 is drained by the solvent drain pipe 86. I have.

In the drying chamber 61, N at room temperature is used as a drying gas.
_An N ₂ gas supply circuit 90 is provided as gas supply means for supplying ₂ (nitrogen) gas or hot N ₂ gas.

The inlet of the _{N 2} gas supply circuit 90 supplies, for example the ambient temperature of the _{N 2} gas _{N 2} gas supply source (not shown) is connected. The N ₂ gas supply circuit 90 includes an on-off valve 9.
1, a flow controller 92, and a heater 93 for heating the N ₂ gas are sequentially provided. The outlet of the N ₂ gas supply circuit 90 is
Gas nozzles 9 arranged in pairs above the drying chamber 61
4,94. It should be noted that a normal temperature N ₂ gas can be supplied to the drying chamber 61 by bypassing the heater 93.
Bypass circuit 95 are connected as shown in the N ₂ gas supply circuit 90. In the bypass circuit 95, an on-off valve 96,
Flow rate controllers 97 are sequentially provided.

An exhaust pipe 98 for exhausting the indoor atmosphere is connected to the side wall of the drying chamber 61. The exhaust pipe 98 is provided with a flow control valve 99 to freely adjust the exhaust amount of the exhaust pipe 98. Further, a lid 100 for opening and closing a loading / unloading port 61a formed on the upper surface of the drying chamber 61 is provided. The lid 100 is vertically movable and horizontally movable by a moving mechanism (not shown).

As shown in FIG. 3, the rinsing / drying device 21
Is provided with a wafer guide 62. The wafer guide 62 is moved vertically (FIG. 3) by an elevating mechanism (not shown).
(Z direction in the middle). The wafer guide 62 includes a shaft portion 105, a guide portion 106, and three parallel holding members 107a, 107b, and 107c fixed to the guide portion 106 in a horizontal posture. In each of the holding members 107a to 107c, 50 grooves 108 for holding the lower part of the periphery of the wafer W are formed at equal intervals. Therefore, the wafer guide 62 is configured to hold 50 wafers W arranged at equal intervals and to move up and down between the processing tank 60 and the drying chamber 61.

Next, the processing according to the embodiment of the present invention performed in the rinsing / drying apparatus 21 configured as described above will be described along with the cleaning processing performed in the cleaning apparatus 1. First, a transfer robot (not shown) stores a carrier C containing, for example, 25 wafers W that have not been cleaned yet.
Are mounted on the loading stage 5 of the loading / unloading section 2. Then, for example, the carrier C
50 wafers W for two wafers are taken out of the carrier C, and
The transfer device 30 collectively holds the wafers W in units of 50 wafers. Then, the wafers W are transferred to the transfer devices 31, 32,
33, each wafer cleaning device 12-15,
Conveyed sequentially to 17-19. Thus, cleaning for removing impurities such as particles attached to the surface of the wafer W is performed. Finally, the rinsing / drying device 21 performs a final rinsing and drying process, and carries out the carrier C via the loading / unloading unit 50 to the outside of the device.

Here, the processing of the rinsing / drying apparatus 21 will be described with reference to the flowchart shown in FIG. 4 and the first to sixth process explanatory diagrams shown in FIGS. In addition,
As the solvent, for example, dichloromethane (liquid) which has a higher specific gravity than pure water, is hydrophobic, and is difficult to mix with pure water will be described as an example.

First, the lid 100 is opened to open the loading / unloading port 61a, and the wafer guide 62 is raised to the drying chamber 61. The transfer device 33 uses the DHF
The washed wafer W is carried into the rinsing / drying device 21 and transferred to the wafer guide 62. On the other hand, as shown in FIG. 2, the on-off valve 66 is opened, and the pure water from the pure water supply circuit 65 is supplied and filled into the processing tank 60 through the jet nozzle 68 (FIG. 5).

Next, the lid 100 is closed and the wafer guide 62 is lowered to store the wafer W in the processing tank 60. As shown in FIG. 6, the wafer R is immersed in pure water to perform final rinse cleaning (S1 in FIG. 4).

After the final rinsing, the on-off valve 66 is closed and the on-off valve 71 is opened, and dichloromethane is supplied into the inner tank 63 by the solvent supply circuit 70 as shown in FIG. 7 (S2 in FIG. 4). As described above, dichloromethane has a higher specific gravity than pure water, and thus sinks and accumulates at the bottom of the processing tank 60. On the other hand, pure water is gradually drained from the upper part of the processing tank 60 in accordance with the supply of dichloromethane, and a pure water layer and a dichloromethane layer are formed in the inner tank 63. While the dichloromethane layer is accumulated and thickens the dichloromethane layer, pure water is driven out of the inner tank 63 to make the pure water layer thinner.
As shown in FIG. 8, the liquid filled in the inner tank 63 is completely replaced with dichloromethane. Thus, the state where the wafer W is immersed in pure water is changed to a state where it is immersed in dichloromethane (S3 in FIG. 4). Therefore, the water droplets adhering to the surface of the wafer W can be replaced with dichloromethane in the liquid without contacting with an external atmosphere (such as air). Further, water droplets adhering to the surface of the wafer guide 62, the inner peripheral surface of the groove 108, and a part of the wafer W held in the groove 108, such as the lower part of the periphery, can be easily replaced with dichloromethane. The N ₂ gas supply circuit 9
At 0, a normal temperature N ₂ gas or hot N ₂ (nitrogen) gas is supplied to make the inside of the drying chamber 61 an inert atmosphere. Alternatively, the inside of the drying chamber 61 may be constantly replaced with a fresh inert atmosphere by exhausting air through the exhaust pipe 98.

After the replacement, the wafer guide 62 is raised as shown in FIG. 9 (S4 in FIG. 4). The wafer W is lifted out of dichloromethane and introduced into the drying chamber 61 while being exposed to the N ₂ atmosphere. The dichloromethane adhering to the surface of the wafer W is naturally evaporated to dry the wafer W. Further, as shown in FIG. 10, a normal temperature N ₂ gas or a hot N ₂ gas may be discharged onto the surface of the wafer W (S in FIG. 4).
5). Thereby, the evaporation of dichloromethane progresses, and the drying can be promoted. After drying, the discharge of the normal temperature N ₂ gas or hot N ₂ gas is stopped. And the lid 10
0 is opened, and the transfer device of the loading / unloading unit 50 unloads the wafer W from the rinsing / drying device 21.

According to the rinsing / drying apparatus 21, water droplets adhering to the surface of the wafer W in the liquid are replaced with dichloromethane without touching air, and the wafer W having dichloromethane adhered thereto is then dried. The wafer W can be dried without generating a watermark. Therefore, formation of a natural oxide film due to the watermark can be prevented, and defects of semiconductor devices manufactured on the surface of the wafer W can be reduced.

Since dichloromethane does not dissolve the resist film, the wafer W with the resist film can be suitably dried. As a result, pattern collapse can be prevented, and defects of the semiconductor device can be reduced. Further, dichloromethane does not contain a flammable component such as alcohol, and is supplied to the processing tank 60 in a liquefied state at normal temperature, for example. Compared to drying the wafer W by using it, there is less danger and high-level safety measures and equipment are not required.

If the heat of vaporization of dichloromethane is large, heat is taken from the wafer W when the dichloromethane evaporates, and the surface temperature of the wafer W decreases. In such a case, vapor in the atmosphere may condense and water droplets may adhere to the surface of the wafer W. However, according to the rinsing / drying device 21, the drying chamber 61 (above the processing tank 60) is filled with the N ₂ atmosphere so that the atmosphere does not contain steam,
Adhesion of water droplets during dichloromethane evaporation can be prevented.

Water droplets are also replaced with dichloromethane from the water droplets on the inner peripheral surface of the groove 108 and on the surface of a detailed portion such as the lower part of the peripheral edge of the wafer W held in the groove 108. Therefore, when the wafer W is lifted into the drying chamber 61, dichloromethane is evaporated, and the lower peripheral portion of the wafer W can be easily dried. In addition, since it is only necessary to lift the wafer W out of dichloromethane, it is necessary to remove the water droplets by the Marangoni effect by slowly lifting the wafer W from the pure water into the IPA atmosphere as in the conventional case. The rising time of the wafer W can be reduced.

Next, the rinsing method according to the second embodiment is described.
The drying device 110 will be described. The rinsing / drying device 21 is configured to supply hot N ₂ gas to the wafer W in the drying chamber 61. The rinsing / drying device 110 is configured to supply hot N ₂ gas to the wafer W in the processing bath 60. That is, as shown in FIG. 11, the gas nozzles 94 are arranged in a pair above the processing tank 60. The gas nozzle 94,
Except for the arrangement of 94, the rinsing / drying device 21 described above is used.
2 and FIG. 11, the same reference numerals are given to components having the same functions and configurations, and redundant description will be omitted.

The process of the rinsing / drying device 110 is described with reference to a flowchart shown in FIG. 12 and FIGS.
This will be described based on the first to third process explanatory diagrams shown in FIG. Note that dichloromethane is used as the solvent as described above.

First, the steps similar to those of the rinsing / drying apparatus 21 are performed from the loading of the wafer W to the immersion of the wafer W in dichloromethane as shown in FIG. 13 (S1 to S3 in FIG. 12). ). Also, gas nozzles 94, 94
Hot N ₂ gas is discharged from the process tank to make the surroundings of the processing tank 60 into an N ₂ atmosphere. Next, as shown in FIG. 14, dichloromethane is drained from the inner tank 63 (S in FIG. 12).
4). As the liquid level of dichloromethane falls, the wafer W is exposed. The dichloromethane adhering to the exposed surface of the wafer W evaporates spontaneously. As shown in FIG. 15, almost all dichloromethane is drained from the inner tank 63.
Further, drying may be promoted by supplying hot N ₂ gas to the wafer W (S5 in FIG. 12). Thereafter, the wafer guide 62 is raised to carry out the wafer W.

According to the rinsing / drying device 110,
Similar to the rinsing / drying device 21, a substrate with a resist film can be safely dried without generating a watermark and without pattern collapse. In addition, the wafer W
Can be easily dried.

Next, the rinsing method according to the third embodiment will be described.
The drying device 120 will be described. Each of the rinsing / drying devices 21 and 110 is configured to supply a solvent having a specific gravity higher than that of pure water. However, the rinsing / drying device 120 supplies a solvent whose specific gravity is lighter than pure water. It is configured as follows. This solvent is nonflammable like dichloromethane, except that it has a lower specific gravity than pure water, and has the property of not dissolving the resist film.

That is, as shown in FIG.
Has an inner tank 122 and an outer tank 123. Above the processing tank 121, solvent nozzles 124, 124 are arranged in pairs. These solvent nozzles 124, 124
Is connected to a solvent supply circuit 125. A solvent supply source (not shown) is connected to an inlet of the solvent supply circuit 125, and an on-off valve 126 and a flow rate controller 127 are sequentially provided in the solvent supply circuit 125. In addition, processing tank 1
Except that solvent nozzles 124 and 124 are provided on the upper part of 21, the rinsing / drying device 21 has the same configuration as that of the rinsing / drying device 21 described above. Are denoted by the same reference numerals, and redundant description is omitted.

The processing of the rinsing / drying apparatus 120 will be described with reference to the first to fourth process explanatory diagrams shown in FIGS. Since the flow of the processing is basically the same as that of the rinsing / drying device 21, the flowchart shown in FIG. 4 is used.

First, the steps similar to those of the rinsing / drying apparatus 21 are performed until the wafer W is immersed in pure water as shown in FIG. After the final rinse cleaning, the on-off valve 126 opens, and as shown in FIG.
The solvent is supplied into the inner tank 122 by the solvent supply circuit 125 (S2 in FIG. 4). Since the solvent has a lower specific gravity than pure water as described above, it floats above the processing tank 121. On the other hand, pure water is gradually drained from the inner tank 122 through the pure water drain pipe 81 below the processing tank 121 in accordance with the supply of the solvent.
A pure water layer and a solvent layer are formed in the inner tank 122. in this case,
It is preferable that the supply amount of the solvent per unit time and the drainage amount of the pure water be the same. While the solvent is accumulated and the solvent layer is thickened, the pure water is driven out of the inner tank 122 to make the pure water layer thinner. As shown in FIG. 19, the liquid filled in the inner tank 122 is entirely replaced with a solvent, and the wafer W is immersed in the solvent (S3 in FIG. 4). As described above, even when the solvent is lighter than the specific gravity of pure water, the water droplets adhering to the surface of the wafer W can be replaced with the solvent in the liquid without making contact with the external atmosphere. After the replacement, as shown in FIG. 20, the wafer guide 62 is raised (S4 in FIG. 4), and the wafer W
The solvent adhering to the surface of the wafer W is spontaneously evaporated, and a normal temperature N ₂ gas or hot N ₂ gas is discharged onto the surface of the wafer W (FIG.
S5).

According to the rinsing / drying device 120,
The same operation and effect as those of the rinsing / drying devices 21 and 110 can be obtained.

In the rinsing / drying device 120, the wafer W can be immersed in the solvent without draining all the pure water from the processing tank 121. That is, the process of FIG. 19 is replaced with the process of FIG. As shown in FIG. 21, a solvent is supplied into the processing tank 121, and pure water is drained.
The solvent layer is formed to such an extent that the wafer W and the wafer guide 62 can be sufficiently immersed. The wafer guide 62 is raised to immerse the wafer W in the solvent layer. This also allows the water droplets adhering to the surface of the wafer W to be replaced with a solvent in the liquid without contacting the external atmosphere. Also,
The wafer W does not have to be stationary and not immersed in the solvent.
That is, a solvent layer is formed and the wafer W is
By pulling it up from the inside and passing it through the solvent layer at this time, it is possible to replace the state in which the wafer W is in contact with pure water with the state in which the wafer W is in contact with the solvent.

Next, the rinsing method according to the fourth embodiment is described.
The drying device 140 will be described. The rinsing / drying device 140 is configured to supply a solvent having a specific gravity lower than that of pure water and to supply a normal temperature N ₂ gas or a hot N ₂ gas to the wafer W in the processing tank 121. That is,
As shown in FIG. 22, the gas nozzles 94 are arranged in a pair above the processing tank 121.

The processing of the rinsing / drying device 140 is performed by the rinsing / drying device 110 described above with reference to FIGS.
This is basically the same as the process described based on FIG. That is,
First, after immersing the wafer W in the solvent, the solvent is drained from the inside of the inner tank 122, and a normal temperature N ₂ gas or a hot N ₂ gas is supplied to the wafer W in the processing tank 121. According to the rinsing / drying device 140, the rinsing / drying device 2
Operations and effects similar to those of 1,110,120 can be obtained.

As another example of the dichloromethane or HMDS exemplified above as a treatment liquid having a specific gravity higher than that of pure water and being hydrophobic and not dissolving the resist film, HF is used.
E (hydrofluoroether). Commercial HFE
For example, HFE-7 manufactured by Sumitomo 3M Limited
100 are known. This commercially available HFE (such as HFE-7100 manufactured by Sumitomo 3M Ltd.) is supplied into the inner tank 63, for example, as in the first embodiment of the present invention described above. When the pure water layer and the HFE layer are formed on the surface of the wafer W, the state of the interface between the HFE and the pure water is as shown in FIG. That is, on the surface of the wafer W, the interface between the HFE and the pure water is lowered, and the contact state is such that pure water enters the HFE side.

If HFE is further supplied into the inner tank 63 in this state to raise the interface between HFE and pure water, the HFE replaces the liquid filled in the inner tank 63 with HFE. Also, a very small amount of pure water may remain on the surface of the wafer W, that is, as shown in FIG.
The surface of the wafer W is in an interface state where pure water enters the HFE side, so that pure water adhering to the surface of the wafer W is drawn in, and fine pure water remains without being replaced by HFE.
When the wafer W is dried, there is a possibility that a watermark or the like remains in a portion where pure water remains.

In order to solve this problem, as shown in FIG. 24, the surface of the wafer W must be in a state where HFE enters the pure water side to make it difficult for pure water to be drawn into the HFE side. Considered valid. Therefore, next, rinsing / drying apparatuses 150 and 160 according to the fifth and sixth embodiments of the present invention will be described assuming that an interface is formed such that HFE enters the pure water side.

FIG. 25 is a piping diagram of a rinsing / drying device 150 according to a fifth embodiment of the present invention. In the rinsing / drying device 150, the solvent supply circuit 70
IP to supply PA (isopropyl alcohol)
The A supply circuit 151 is connected. An IPA solvent supply source (not shown) is connected to an entrance of the IPA supply circuit 151. The on-off valve 1 is provided in the IPA supply circuit 151.
52, a flow controller 153 is sequentially provided.
Except for the point that the IPA supply circuit 151 is provided, the configuration is the same as that of the rinsing / drying apparatus 21 described above. Therefore, in FIG. 2 and FIG. By assigning the same reference numerals, duplicate description will be omitted.

The processing of the rinsing / drying device 150 is basically the same as that of the rinsing / drying device 21 described above with reference to FIGS. 4 and 5 to 10. However, unlike the above case, HFE (for example, HFE-7100 manufactured by Sumitomo 3M Limited) is used as the solvent.

First, the wafer W is immersed in pure water for final rinsing, and after rinsing, HFE is supplied into the inner tank 63 by the solvent supply circuit 70. At this time, an appropriate amount of IPA is supplied from an IPA supply circuit 151 provided in the solvent supply circuit 70, and the IPA is mixed into the HFE. While HFE sinks and accumulates at the bottom of the processing tank 60, pure water is gradually drained from the upper part of the processing tank 60, and a pure water layer and an HFE layer are formed in the inner tank 63.

In this case, since a small amount of IPA is mixed in HFE, a thin IPA film is formed at the interface between pure water and HFE, and the contact angle with the wafer W (the contact angle at the interface) changes. 24, an interface can be formed on the surface of the wafer W such that HFE enters the pure water side. That is, the interface of the pure water is inclined upward (in the direction in which the interface between the pure water and the HFE moves in the process of replacing the pure water in the inner tank 63 with the HFE) as shown in FIG. . This makes it possible to create a state in which pure water is hardly drawn into the HFE side. And the inner tank 63
After replacing the inside with HFE, the wafer W is pulled up and dried.

According to the rinsing / drying device 150, even when HFE is used as a solvent, pure water in contact with the wafer W can be smoothly replaced with HFE, and fine water droplets are formed on the surface of the wafer W. There is no need to worry about remaining watermarks, and the generation of watermarks can be effectively prevented.

Next, FIG. 26 is a piping diagram of a rinsing / drying device 160 according to a sixth embodiment of the present invention.
In the rinsing / drying device 160, the solvent supply circuit 70
Further, a heater 161 for heating the solvent is provided.
Except that the heater 161 is provided, the rinsing / drying device 21 has the same configuration as that of the rinsing / drying device 21 described above. Therefore, in FIG. 2 and FIG. The duplicate description will be omitted by appending.

The processing of the rinsing / drying device 160 is basically the same as that of the rinsing / drying device 21 described above with reference to FIGS. 4 and 5 to 10. In addition, HFE (for example, HFE-7100 manufactured by Sumitomo 3M Limited) is used as the solvent.

First, the wafer W is immersed in pure water for final rinsing, and after rinsing, HFE is supplied into the inner tank 63 by the solvent supply circuit 70. At this time, the HFE is heated by the heater 161 provided in the solvent supply circuit 70.
While HFE sinks and accumulates at the bottom of the processing tank 60, pure water is gradually drained from the upper part of the processing tank 60, and a pure water layer and an HFE layer are formed in the inner tank 63.

Since the temperature of the HFE is raised, the contact angle with respect to the wafer W (the contact angle at the interface between the pure water and the HFE) also changes in this case, and as described above with reference to FIG.
An interface is formed on the surface of the wafer W such that HFE enters the pure water side, that is, the interface of the pure water is upward (see FIG. 24). (In the direction in which the interface between water and HFE moves), which makes it possible to create a state in which pure water is hardly drawn into the HFE side. Then, the inside of the inner tank 63 is HFE
After the replacement, the wafer W is pulled up and dried.

The rinsing / drying device 160 also
Pure water in contact with the wafer W can be smoothly replaced with HFE, and even if HFE is used as a solvent, there is no fear that minute water droplets remain on the surface of the wafer W, and the generation of watermarks can be effectively prevented. .

Although some embodiments of the present invention have been described, the present invention is not limited to the above-described examples, but can take various forms. For example, the rinsing / drying device 2
In 1, 110, 150, and 160, dichloromethane (a solvent having a higher specific gravity than pure water) was supplied from the lower part of the processing tank 60, but may be supplied from the upper part of the processing tank 60. Further, in the rinsing / drying devices 120 and 140, a solvent having a lower specific gravity than pure water is supplied from the upper part of the processing tank 121, but a solvent having a lower specific gravity may be supplied from the lower part of the processing tank 121. In addition, the rinsing / drying devices 21 and 1
The devices 10, 120, 140, 150, and 160 may be configured as so-called one-bath type devices that can perform not only rinsing with pure water but also chemical cleaning with a chemical such as hydrofluoric acid. This makes it possible to continuously perform the chemical cleaning and the rinsing cleaning in the processing tank 60, thereby saving the footprint and improving the throughput.

The present invention can be applied not only to batch-type processing for processing a plurality of substrates at once, but also to single-wafer processing for processing substrates one by one. Also,
The substrate is not limited to the wafer W, but may be an LCD substrate, a CD,
It may be a substrate, a printed substrate, a ceramic substrate, or the like.

[0081]

According to the present invention, a substrate with a resist film can be formed without causing a watermark and without pattern collapse.
It can be processed safely. As a result, for example, a high-precision semiconductor device manufacturing technique can be realized, and the yield can be improved.

In the processing tank, for example, water droplets adhering to the surface of the substrate can be replaced with the second processing liquid in the liquid without contacting the external atmosphere. Further, since, for example, the second processing liquid adhering to the substrate is evaporated above the processing tank or the second processing liquid adhering to the substrate is evaporated in the processing tank, the substrate can be removed without generating a watermark. Can be dried. Further, compared with the conventional method of drying the substrate using flammable IPA vapor, the risk is reduced and high-level safety measures and equipment are not required.

After the substrate is replaced with a state in which the substrate is brought into contact with the second processing liquid, the substrate is dried to prevent water droplets from adhering during evaporation of the second processing liquid. ADVANTAGE OF THE INVENTION According to this invention, a board | substrate with a resist film can be dried suitably, for example, and can also aim at safety.

Further, for example, water droplets adhering to the periphery of the substrate held by the holding means can be replaced with the second processing liquid in the liquid without contacting the liquid with an external atmosphere.

Further, even when HFE is used as the second processing liquid, there is no fear that minute water droplets or the like remain on the surface of the substrate, and the generation of a watermark can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view of a cleaning apparatus provided with a rinsing / drying apparatus according to an embodiment of the present invention.

FIG. 2 is a piping diagram of a rinsing / drying apparatus according to the first embodiment.

FIG. 3 is a perspective view of a wafer guide.

FIG. 4 is a flowchart of a process performed by the rinsing / drying device of FIG. 2;

FIG. 5 is a first process explanatory view illustrating a process performed by the rinsing / drying device of FIG. 2;

FIG. 6 is a second process explanatory view for explaining a process performed by the rinsing / drying device of FIG. 2;

FIG. 7 is an explanatory view of a third step for explaining processing performed by the rinsing / drying apparatus of FIG. 2;

FIG. 8 is a fourth process explanatory view illustrating a process performed by the rinsing / drying device of FIG. 2;

FIG. 9 is a fifth process explanatory view illustrating a process performed by the rinsing / drying device of FIG. 2;

FIG. 10 is a sixth process explanatory view illustrating the process performed by the rinsing / drying device of FIG. 2;

FIG. 11 is a piping diagram of a rinsing / drying apparatus according to a second embodiment.

FIG. 12 is a flowchart of a process performed by the rinsing / drying device of FIG. 11;

FIG. 13 is a first process explanatory view illustrating a process performed by the rinsing / drying device of FIG. 11;

FIG. 14 is a second process explanatory view illustrating a process performed by the rinsing / drying device of FIG. 11;

FIG. 15 is a third process explanatory view illustrating the process performed by the rinsing / drying device of FIG. 11;

FIG. 16 is a piping diagram of a rinsing / drying apparatus according to a third embodiment.

FIG. 17 is a first process explanatory view illustrating a process performed by the rinsing / drying device of FIG. 16;

FIG. 18 is a second process explanatory view illustrating a process performed by the rinsing / drying device of FIG. 16;

FIG. 19 is a third process explanatory view illustrating the process performed by the rinsing / drying device of FIG. 16;

FIG. 20 is a fourth process explanatory view illustrating the process performed by the rinsing / drying device of FIG. 16;

FIG. 21 is another third process explanatory view illustrating the process performed by the rinsing / drying device of FIG. 16;

FIG. 22 is a piping diagram of a rinsing / drying apparatus according to a fourth embodiment.

FIG. 23 is an explanatory diagram of a problem to be solved when HFE is used as a second processing liquid.

FIG. 24 is an explanatory diagram in the case where the problem to be solved when HFE is used as the second processing liquid is solved.

FIG. 25 is a piping diagram of a rinsing / drying apparatus according to a fifth embodiment.

FIG. 26 is a piping diagram of a rinsing / drying apparatus according to a sixth embodiment.

[Explanation of symbols]

1 cleaning device 21 rinsing and drying apparatus 60 processing tank 61 drying chamber 62 the wafer guide 65 pure water supply circuit 70 solvent supply circuit 90 N ₂ gas supply circuit W wafer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B08B 3/02 B08B 3/02 C H01L 21/308 H01L 21/308 GF term (Reference) 3B201 AA03 AB13 AB44 BB02 BB21 BB82 BB88 BB90 BB93 BB95 BB99 CC01 CC12 5F043 BB27 EE12

Claims (17)

[Claims] 1. A method of processing a substrate using at least a first processing liquid and a second processing liquid in a processing tank, wherein the substrate is brought into contact with the first processing liquid, A substrate processing method, wherein the substrate is replaced with a state where the substrate is brought into contact with the second processing liquid having a specific gravity different from that of the first processing liquid. 2. When the substrate is replaced with a state in which the substrate is brought into contact with the second processing liquid having a specific gravity different from that of the first processing liquid, the first processing liquid is drained from the processing tank. The substrate processing method according to claim 1, wherein the method is performed. 3. The method according to claim 1, wherein a first processing liquid layer and a second processing liquid layer are formed in the processing tank, and the substrate is moved from the first processing liquid layer to the second processing layer. Claim 1
4. The substrate processing method according to 1. 4. After replacing the substrate in a state where the substrate is brought into contact with the second processing liquid having a specific gravity different from that of the first processing liquid, the substrate is lifted above the processing tank to dry the substrate. 4. The substrate processing method according to claim 1, wherein: 5. After replacing the substrate in a state where the substrate is brought into contact with the second processing liquid having a specific gravity different from that of the first processing liquid, draining the processing tank and drying the substrate. 4. The substrate processing method according to claim 1, wherein the substrate processing method is characterized in that: 6. The substrate processing method according to claim 4, wherein a gas is supplied to the substrate after separating the substrate from the second processing liquid. 7. The substrate processing method according to claim 1, wherein an inert atmosphere is provided around the processing tank. 8. The substrate according to claim 1, wherein a resist film is formed on a surface of the substrate, and the second processing liquid has a property of not dissolving the resist film. 8. The substrate processing method according to 3, 4, 5, 6, or 7. 9. The substrate processing method according to claim 1, wherein the second processing liquid is nonflammable. 10. The method according to claim 1, wherein IPA is mixed with the second processing liquid.
10. The substrate processing method according to 7, 8, or 9. 11. The substrate processing method according to claim 1, wherein the second processing liquid is heated. 12. An apparatus for processing a substrate in a processing tank, comprising: holding means for holding the substrate in the processing tank; and a first processing liquid supply for supplying a first processing liquid into the processing tank. Means for supplying a second processing liquid having a specific gravity different from that of the first processing liquid into the processing tank. 13. A first processing liquid discharging means for discharging the first processing liquid from the processing tank, and a second processing liquid for discharging the second processing liquid from the processing tank. 13. The substrate processing apparatus according to claim 12, further comprising a drain unit. 14. The substrate processing apparatus according to claim 12, wherein the holding unit is capable of moving up and down between the inside of the processing tank and the upper part of the processing tank. 15. The substrate processing apparatus according to claim 12, further comprising gas supply means for supplying a gas for promoting drying to the substrate. 16. The substrate processing apparatus according to claim 12, further comprising an IPA supply unit that mixes IPA with the second processing liquid. 17. The apparatus according to claim 12, further comprising heating means for heating said second processing liquid.
17. The substrate processing apparatus according to 4, 15, or 16.