JP2000279899A - Method and apparatus for treating spin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decompose/remove organic substances adherent to a semiconductor wafer efficiently. SOLUTION: In a treatment apparatus, a semiconductor wafer U held by a rotating rotor 12 is cleaned, and a nozzle 41 which ejects an oxygen-containing treatment liquid toward a substrate and an ultraviolet ray source 42 which is placed above the rotor 12 and emits ultraviolet rays to the oxygen-containing treatment liquid ejected on the substrate are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a spin processing apparatus and a spin processing method for performing a cleaning process while rotating a substrate such as a semiconductor wafer or a glass substrate.

[0002]

2. Description of the Related Art In a semiconductor manufacturing apparatus, a liquid crystal manufacturing apparatus and the like, there is a lithography process for forming a circuit pattern on a semiconductor wafer or a glass substrate as a substrate. In this lithography process, as is well known, a resist is applied to the substrate, and the resist is irradiated with light through a mask on which a circuit pattern is formed. The circuit pattern is formed by repeating a series of steps several tens of times such as removing the removed portion and etching the removed portion.

In the above-mentioned series of steps, if the substrate is contaminated, it becomes impossible to form a circuit pattern precisely, which causes defective products. Therefore, when a circuit pattern is formed in each step, the substrate is washed in a clean state in which resist, dust, organic substances, and the like do not remain.

[0004] As the apparatus for cleaning the substrate, a batch method in which a plurality of semiconductor wafers are immersed in a cleaning tank containing a processing liquid for cleaning, or a method in which one substrate is rotated to process the substrate. There is a single-wafer system in which a cleaning process is performed by spraying a liquid, and a single-wafer system having a high cleaning effect tends to be used as a substrate becomes larger.

As a single wafer type cleaning apparatus, there is a spin processing apparatus for performing cleaning while rotating a substrate. The spin processing apparatus has a rotating body that is driven to rotate, holds the substrate on the rotating body, and performs a cleaning process on the substrate by spraying a processing liquid onto the substrate while rotating the rotating body in this state. Like that.

When the dirt attached to the substrate is an organic substance,
A mixture of sulfuric acid and hydrogen peroxide, an alkaline cleaning solution, ozone water, or the like is sprayed on the substrate as a processing solution. When ozone water is used as the processing liquid, ozone in the ozone water sprayed on the substrate is decomposed into oxygen and active oxygen,
Of these, active oxygen reacts and decomposes organic substances to remove the organic substances from the substrate, whereby a cleaning effect can be obtained.

[0007]

However, simply injecting ozone water into a rotatably driven substrate does not sufficiently decompose ozone in the ozone water. As a result, active oxygen generated on the substrate onto which the ozone water has been jetted is not sufficiently generated, and thus the organic substance attached to the substrate may not be sufficiently decomposed.

In addition, if the ozone in the ozone water is not sufficiently decomposed, the concentration of ozone gas contained in the waste liquid will increase, and the waste liquid will cause early corrosion of the piping system, and the waste liquid will require much labor. Sometimes it hangs.

The present invention increases the degree of decomposition of an oxygen-containing treatment solution sprayed on a substrate, thereby improving the cleaning effect of the substrate and reducing the concentration of ozone gas contained in the waste liquid. An object of the present invention is to provide a processing apparatus and a method thereof.

[0010]

According to a first aspect of the present invention, there is provided a spin processing apparatus for performing a cleaning process on a substrate held by a rotatably driven rotary body, wherein the nozzle body jets an oxygen-containing processing liquid toward the substrate. And ultraviolet irradiation means arranged above the rotating body and irradiating the oxygen-containing treatment liquid sprayed on the substrate with ultraviolet light.

According to a second aspect of the present invention, there is provided a spin processing method for cleaning a substrate held by a rotating body driven by rotation, wherein a step of injecting an oxygen-containing processing liquid toward the substrate, Irradiating the oxygen-containing treatment liquid with ultraviolet rays.

According to the first and second aspects of the present invention, the oxygen-containing treatment liquid sprayed on the substrate is irradiated with ultraviolet rays to promote the decomposition thereof, so that the organic substances adhered to the substrate can be efficiently removed. It can be decomposed and removed, and the decomposition is promoted, so that the amount of ozone gas contained in the wastewater can be reduced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a spin processing device, which has a cup body 1. The cup body 1 includes a lower cup 3 provided on a mounting plate 2 and an upper cup 4 provided on the upper side of the lower cup 3 so as to be vertically driven by a vertical driving mechanism (not shown).

The center of the bottom wall of the lower cup 3 and the mounting plate 2
The upper cup 4 is formed with a through hole 5 penetrating therethrough, and the peripheral wall 3a of the lower cup 3 is slidably inserted into the double peripheral wall 4a of the upper cup 4 to form a labyrinth structure by these peripheral walls. ing.

The upper surface of the upper cup 4 is open, and when the upper cup 4 is driven in the downward direction, for example, a semiconductor wafer U as a substrate washed in the cup body 1 is taken out as described later. Or an uncleaned semiconductor wafer U can be supplied. Further, one ends of a plurality of discharge pipes 6 are connected to the bottom wall of the lower cup 3 at predetermined intervals in a circumferential direction, and the other ends are connected to a suction pump (not shown). Thereby, the processing liquid scattered in the cup body 1 by cleaning or drying the semiconductor wafer U is discharged.

A base 7 is arranged on the lower surface side of the cup body 1. A mounting hole 8 is formed in the base 7 at a position corresponding to the through hole 5 of the cup body 1, and the mounting hole 8 has a stator 9a of a pulse control motor 9 constituting driving means. Is fitted and fixed.

The stator 9a has a tubular shape, and a tubular rotor 9b is rotatably fitted therein. A cylindrical connecting body 11 is provided on the upper end surface of the rotor 9b.
Are fixed integrally by joining the lower end surfaces. A flange 11a having a diameter larger than the inner diameter of the stator 9a is formed on the lower end surface of the connecting body 11. The flange 11a is slidably joined to the upper end surface of the stator 9a, thereby restricting the rotor 9b from falling off the stator 9a without preventing the rotation of the rotor 9b. .

The connecting body 11 is provided with the through hole 5 of the cup body 1.
From the inside, and a disk-shaped rotating body 12
Is attached and fixed. A plurality of the peripheral portions of the upper surface of the rotating body 12 are arranged at predetermined intervals in the circumferential direction.
Six holding members 13 are rotatably provided at 0 degree intervals.

As shown in FIG. 2, the holding member 13 has a cylindrical portion 13a whose upper surface is closed, and a support shaft 13b vertically suspended from the lower surface of the upper wall of the cylindrical portion 13a. Are rotatably supported by bearings 13c provided on the rotating body 12.

The lower end of the support shaft 13b protrudes from the lower surface of the rotating body 12, and a small gear 14 is attached to the protruding end.

The small gear 14 is a parent gear 1 partially formed on the outer periphery of a flange member 16 provided rotatably with respect to the connecting body 11 on the lower surface side of the rotating body 12.
6a.

As shown in FIG. 1, an urging spring 17 is provided on the outer periphery of the connecting member 11. This biasing spring 17
Urges the flange member 16 in a predetermined direction. Thus, the support member 13 can be rotated in a predetermined direction via the small gear 14.

A support pin 21 is detachably provided at an eccentric position on the upper end surface of the support portion cylindrical portion 13a. A tapered surface 23 is formed on the support pin 21, and a projection 24 is formed on the top of the tapered surface 23.

A semiconductor wafer U as a substrate is supplied into the cup body 1 by a robot (not shown) or the like. When the semiconductor wafer U is supplied into the cup body 1, the support member 13 is rotated by a release means 27 described later against the urging force of the urging spring 17.

The semiconductor wafer U supplied into the cup body 1 is supplied into the cup body 1 such that the lower peripheral edge of the outer periphery engages with the tapered surface 23 of each of the support pins 21. In this state, when the release state by the release means 27 is removed,
Since the support member 13 is rotated by the urging force of the urging spring 17 and the support pin 21 is eccentrically rotated in conjunction with the rotation, the lower edge of the semiconductor wafer U is held by the tapered surface 23 and the projection 24. It has become.

The release of the holding state of the semiconductor wafer U by the support pins 21 is performed by the release means 27.
As shown in FIG.
8, an arm 29 driven by the release cylinder 28, and a release pin 3 provided at the upper end of the arm 29.
It consists of 1.

With the release cylinder 28 operating and the release pin 31 preventing the rotation of the flange member 16,
The rotating member 12 is rotated by a predetermined angle by the pulse control motor 9 against the urging force of the urging spring 17, whereby the holding member 13 is rotated and the support pin 1 is rotated.
3, the locked state of the semiconductor wafer U is released.

A through hole 12a is formed in the center of the rotating body 12. The rotor 9b has a hollow fixed shaft 3
2 and the upper end of the fixed shaft 32 is
In the through hole 12a. A nozzle head 33 is fitted on the upper end of the fixed shaft 32. The nozzle head 33 is provided with a plurality of lower cleaning nozzles 34 for injecting a processing liquid such as pure water toward the lower surface of the semiconductor wafer U held by the rotating body 12, and for drying, for example, nitrogen or the like. A gas nozzle (not shown) for injecting the above gas is provided.

The lower end of the fixed shaft 32 has a pulse control mode.
It is fitted and fixed in a support hole 35 a of a support 35 disposed on the lower surface side of the table 9. The support 35 is provided with a brake cylinder 36. This brake cylinder 36
The drive shaft is provided with a brake 37. The brake 37 is operated by a brake cylinder 36 so as to be connected to a brake disk 38 provided on the lower end face of the pulse control motor 9. Crimp. Thus, the rotation of the rotor 9b of the pulse control motor 9 is prevented.

That is, when the rotating body 12 is rotated by a predetermined angle against the urging force of the urging spring 17 and the locked state of the semiconductor wafer U by the projection 24 is released, the pulse control mode is caused by a power failure or the like. Even if the driving force of the motor 9 is lost, the rotating body 12 is prevented from rotating by the restoring force of the biasing spring 17. Thus, even when a power failure occurs, the release state of the semiconductor wafer U by the release means 17 can be reliably maintained.

The upper surface of the rotating body 12 has a turbulence prevention cover.
Covered by 39. The turbulence prevention cover 39 has an opening 39a for exposing the nozzle head 33,
An opening 39b for exposing the holding member 13 is formed. The turbulence prevention cover 29 is provided on the support pin 14.
The semiconductor wafer U is separated from the lower surface of the semiconductor wafer U supported at a predetermined interval by the rotation of the rotating body 12.
The turbulence of the air flow is prevented on the lower surface side.

A semiconductor wafer U is provided above the cup body 1.
An upper nozzle body 41 for injecting ozone water as an oxygen-containing treatment liquid is provided on the upper surface of the nozzle. Further, the support pin 2
Above the semiconductor wafer U held at 1, an ultraviolet light source 42 such as a low-pressure UV lamp having a wavelength of 185 nm or 254 nm or an excimer lamp having a wavelength of 172 nm is provided as an irradiation means for irradiating the upper surface of the semiconductor wafer U with ultraviolet light. Have been. As the ultraviolet light source 42, a surface-emitting ultraviolet light source, a spiral annular ultraviolet light source, or the like is used so that the entire upper surface of the semiconductor wafer U can be irradiated substantially uniformly.

Next, a case where the semiconductor wafer U is cleaned by the spin processing apparatus having the above configuration will be described. First, the semiconductor wafer U is supplied into the cup body 1, and when the rotating body 12 is rotated while the peripheral portion thereof is held by the support pins 21, the ozone water is directed from the upper nozzle body 41 toward the upper surface of the semiconductor wafer U. Inject. At the same time, the ultraviolet light source 42 is turned on, and the upper surface of the semiconductor wafer U on which the ozone water has been jetted is irradiated with ultraviolet light.

When the ozone water sprayed on the upper surface of the semiconductor wafer U is irradiated with ultraviolet rays, the ozone in the ozone water is decomposed into oxygen and active oxygen. Ozone water decomposes even without irradiation with ultraviolet rays, but it has been confirmed that irradiation with ultraviolet rays significantly improves decomposition efficiency.

According to the experiment, the ozone gas concentration was 20 pp
When the ozone water of m was simply sprayed on the semiconductor wafer U, the ozone concentration of the waste liquid was 10 ppm. However, when the semiconductor wafer U on which the ozone water was sprayed was irradiated with ultraviolet rays, the ozone concentration of the waste liquid was reduced to 2 ppm. It was confirmed that. That is, it was confirmed that the decomposition of the ozone gas contained in the ozone water was promoted by the ultraviolet rays.

As described above, if the decomposition of ozone water is promoted, the amount of active oxygen generated from the ozone water increases, so that organic substances attached to the semiconductor wafer U can be efficiently decomposed and removed in proportion to the increase. become.

In addition, when the efficiency of decomposing ozone water is improved, the concentration of ozone contained in the waste liquid decreases, so that not only the degree of corrosion of the piping system due to the waste liquid decreases, but also the waste liquid treatment becomes easy. .

In the spin processing apparatus, the surface of the semiconductor wafer U to which the ozone water is sprayed is irradiated with ultraviolet rays, so that the ultraviolet light source 42 can be disposed sufficiently close to the semiconductor wafer U. It becomes possible. That is,
The ozone water sprayed on the semiconductor wafer U
Is rotated outwardly in the radial direction and hardly scattered upward. Therefore, even if the ultraviolet light source 42 is sufficiently close to the upper surface of the semiconductor wafer U, the ultraviolet light source 42 Does not scatter and cause early damage.

As described above, by disposing the ultraviolet light source 42 sufficiently close to the semiconductor wafer U, it is possible to improve the efficiency of decomposing ozone in the ozone water by the ultraviolet light. Decomposition and removal can be performed efficiently.

Since the ultraviolet rays have a function of decomposing oxygen to generate active oxygen, the treatment liquid in the present invention is not limited to ozone water, but a liquid containing oxygen, for example, pure water. It may be. That is, if the oxygen-containing treatment liquid is pure water, the oxygen contained therein is decomposed into active oxygen and exhibits an organic matter decomposing action.

Further, the nozzle body for injecting the ozone water may be an ultrasonic cleaning nozzle. By using the ultrasonic cleaning nozzle, not only the cleaning effect by the ultrasonic cleaning can be improved, but also the ultrasonic cleaning can be performed by the ultrasonic cleaning. Is applied, the efficiency of decomposing ozone is further improved, and thus the cleaning effect can be enhanced.

The substrate is not limited to a semiconductor wafer, but may be a glass substrate for liquid crystal.

[0044]

As described above, according to the present invention, the oxygen-containing treatment liquid sprayed on the substrate is irradiated with ultraviolet rays.

As a result, the decomposition of the oxygen-containing treatment solution is promoted by the ultraviolet rays, and the amount of active oxygen generated is increased. Therefore, organic substances attached to the substrate can be efficiently decomposed and removed, and the decomposition is promoted. Thus, the amount of ozone contained in the waste liquid can be reduced, and the treatment can be easily performed.

[Brief description of the drawings]

FIG. 1 is a sectional view of a schematic configuration of a spin processing apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a mounting structure of a support pin for holding a semiconductor wafer.

[Explanation of symbols]

 12 ... Rotating body 41 ... Nozzle body 42 ... Ultraviolet light source (Ultraviolet irradiation means) U ... Semiconductor wafer

Claims (2)

[Claims] 1. A spin processing apparatus for cleaning a substrate held by a rotating body driven by rotation, comprising: a nozzle body for spraying an oxygen-containing processing liquid toward the substrate; and a nozzle body disposed above the rotating body. An ultraviolet irradiation means for irradiating the oxygen-containing treatment liquid sprayed on the substrate with ultraviolet light. 2. A spin processing method for cleaning a substrate held by a rotating body that is driven to rotate, wherein: a step of injecting an oxygen-containing processing liquid toward the substrate; and an oxygen-containing processing liquid injected to the substrate. Irradiating the substrate with ultraviolet light.