JPH1116804A - Liquid treating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate resist edge stripping and eliminate residual resist, by supplying stripper for HMDS removal to the peripheral portion of a workpiece prior to a process of application film formation. SOLUTION: A stripper supply nozzle 4 is moved above the edge portion of a wafer 3 placed on a spin chuck which is rotatable on a rotary shaft 2 as rotational axis. The wafer 3 is turned, and further stripper for HMDS (hexamethylendisilazane) removal is supplied to the edge portion from the stripper supply nozzle 4. Then resist as treatment liquid is supplied from a resist liquid supply nozzle 5 to the wafer 3 to form a resist film as application film on the surface of the wafer 3. Edge rise liquid is supplied to the edge portion from an edge rinse supply nozzle 6, above the edge of the wafer 3, to remove the resist film from the edge portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for performing liquid processing on an object to be processed such as a semiconductor wafer in a semiconductor device manufacturing process.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process, a semiconductor wafer to be processed (hereinafter abbreviated as a wafer) during patterning by photolithography technology.
A coating / development process of applying and developing a resist liquid thereon is performed.

In this coating / developing process, a large amount of the resist liquid is supplied to the peripheral portion of the wafer, so that a phenomenon occurs in which the resist film at the peripheral portion (edge portion) becomes thick.
For this reason, a so-called edge rinse liquid is supplied to the resist film at the edge portion immediately after the application of the resist, thereby removing the resist film at the edge portion (peeling of the resist edge). The peeling of the resist edge is an indispensable process for the currently mainstream positive resist.

[0004]

However, simply supplying the edge rinse solution does not sufficiently remove the resist film at the edge portion. For this reason, at present, a method of exposing only an edge portion to facilitate peeling at the time of development has been performed.

In this method, since the number of exposure steps for the edge portion increases, there is a problem that the throughput is deteriorated. In recent years, a chemically amplified resist has been used, and an exposure process of an edge portion is performed by PEB (Post Exposure).
Bake) is performed after the processing, so that the resist may remain even if edge exposure is performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an efficient liquid processing method in which the resist edge can be easily removed and the resist does not remain.

[0007]

In order to solve the above problems, the present invention takes the following measures. That is, the present invention
A method of performing a liquid treatment on a processing target object by supplying a processing liquid to the processing target object, wherein the processing liquid is supplied to the processing target object which has been subjected to the HMDS process to form a coating film on the surface of the processing target object Forming, and removing a coating film on the peripheral portion by supplying a rinsing liquid to a peripheral portion of the coating film, wherein a stripping solution for removing HMDS is provided before the step of forming the coating film. Is supplied to the peripheral portion of the object to be processed.

According to this configuration, the HMDS is removed because the stripping solution is supplied to the edge portion before the application of the resist solution. For this reason, since HMDS does not exist between the wafer and the resist film at the edge portion, the adhesiveness between the wafer and the resist film relatively decreases. As a result, the relatively thick resist film at the edge portion can be easily removed simply by supplying the edge rinse liquid.

In the liquid treatment method of the present invention, it is preferable to use a polar solvent, for example, a water-soluble solvent such as ethanol, thinner or pure water, or an organic acidic solvent such as hexane or acetic acid as the rinsing liquid. Further, as the rinsing liquid, an edge rinsing liquid such as a thinner may be used.

[0010]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a process chart for explaining the liquid processing method of the present invention.

In the method of the present invention, first, HMDS
A stripping solution for removal is supplied to a peripheral portion of a wafer as a processing object. As shown in FIG. 1 (a), this peels off above an edge portion of a wafer 3 mounted on a spin chuck 1 rotatable around a rotation shaft 2 connected to a driving means (not shown) as a rotation axis. The stripping solution is supplied from the stripping solution supply nozzle 4 to the edge portion while moving the solution supply nozzle 4 and rotating the wafer 3. In this case, the rotation speed of the wafer is 1000 to 200 in consideration of removal of only the edge portion.
It is preferably 0.

In the present invention, the step of supplying the stripping solution to the edge portion of the wafer 3 may be performed before the HMDS processing or after the HMDS processing.

Next, a resist liquid as a processing liquid is supplied to the wafer 3 to form a resist film as a coating film on the surface of the wafer 3. This involves moving the resist solution supply nozzle 5 above the center of the wafer 3 as shown in FIG.
A resist liquid is supplied from the resist liquid supply nozzle 5 to the surface of the wafer 3.

At this time, since the wafer 3 is rotating about the rotating shaft 2 as a rotation axis, the resist solution supplied to the surface of the wafer 3 spreads from the center of the wafer 3 toward the edge portion by centrifugal force, and the entire surface of the wafer 3 Is applied in a uniform thickness. In this case, the rotation speed of the wafer is preferably 2000 to 3000 in consideration of the uniformity of the resist thickness.

Next, a rinsing liquid is supplied to the edge portion of the resist film to remove the resist film at the edge portion. As shown in FIG. 1C, the edge rinse liquid supply nozzle 6 is moved above the edge portion of the wafer 3 and the edge rinse liquid is supplied from the edge rinse liquid supply nozzle 6 while rotating the wafer 3. Supply to parts. In this case, the rotation speed of the wafer is 1 in consideration of removal of only the edge portion.
It is preferably from 000 to 2,000.

In the method of the present invention having the above steps, the HMDS is removed by supplying the stripping solution to the edge portion.
In the edge portion, H between the wafer and the resist film
MDS does not exist, and the adhesion between the wafer and the resist film relatively decreases. As a result, a relatively thick resist film at the edge portion can be easily peeled off only by supplying an edge rinse solution after resist application.

In the above method, when an edge rinse liquid is used as the stripping liquid, the edge rinse liquid supply nozzle 6 can be used as the stripping liquid supply nozzle 4, so that the apparatus can have a simple configuration. .

Next, an embodiment performed to clarify the effect of the present invention will be described. (Example 1) First, a wafer after the HMDS process was carried into a coating unit (coater) by a transfer means, and was placed on a spin chuck installed in the coating unit. Then, while rotating the wafer at a rotation speed of 1000, the edge rinse liquid supply nozzle is brought close to the edge portion, and the edge rinse liquid is supplied from the edge rinse supply nozzle to perform HMDS.
Was removed and washed.

Next, the edge rinse supply nozzle was retracted, the resist liquid supply nozzle was positioned above the center of the wafer, and the resist liquid was supplied from the resist liquid supply nozzle while rotating the wafer at a rotation speed of 2500. The resist liquid supplied to the surface of the wafer spread from the center of the wafer toward the edge by centrifugal force, and was applied with a uniform thickness over the entire surface of the wafer.

Next, the resist supply nozzle is retracted, the edge rinse liquid supply nozzle is again brought close to the edge of the wafer, and the edge rinse liquid is supplied from the edge rinse liquid supply nozzle to the edge while rotating the wafer at a rotation speed of 1000. Then, the resist film at the edge portion was removed.

At this time, the resist film at the edge portion of the wafer was sufficiently removed, and the edge exposure step could be omitted. This improved the throughput by about 3%.

(Example 2) A wafer after HMDS processing was carried into a coating unit (coater) by a transfer means, and was placed on a spin chuck provided in the coating unit. Next, while the wafer is rotated at a rotation speed of 1000, the stripping solution supply nozzle is brought close to the edge portion, and ethanol is supplied as a stripping solution from the stripping solution supply nozzle, and the HMD is removed.
S was removed and washed.

Next, the stripping solution supply nozzle is retracted,
The resist liquid supply nozzle was positioned above the center of the wafer, and the resist liquid was supplied from the resist liquid supply nozzle while rotating the wafer at a rotation speed of 2500. The resist liquid supplied to the surface of the wafer spread from the center of the wafer toward the edge by centrifugal force, and was applied with a uniform thickness over the entire surface of the wafer.

Next, the resist supply nozzle is moved backward, the edge rinse liquid supply nozzle is brought close to the edge of the wafer, and the edge rinse liquid is supplied from the edge rinse liquid supply nozzle to the edge while rotating the wafer at a rotation speed of 1000. Then, the resist film at the edge portion was removed.

At this time, the resist film on the edge portion of the wafer was sufficiently removed, and the edge exposure step could be omitted. This improved the throughput by about 3%.

(Examples 3 and 4) A liquid treatment was performed in the same manner as in Example 2 except that hexane (Example 3) and pure water (Example 4) were used as the stripping solution. As a result, in each case, the throughput was improved by about 3%.

In the above embodiment, the case where a semiconductor wafer is used as the object to be processed is described. However, in the present invention, another substrate such as a glass substrate may be used as the object to be processed.

[0028]

As described above, in the liquid processing method of the present invention, the stripper for removing HMDS is supplied to the peripheral portion of the object before the step of forming the coating film. This is a method that is easy and does not cause residual resist.

In the liquid processing method of the present invention, the edge exposure step and the subsequent cooling step can be reduced, so that the throughput can be improved. Furthermore, since edge exposure is not required, the number of edge exposure units can be reduced, which can contribute to space saving.

[Brief description of the drawings]

FIGS. 1A to 1C are process diagrams for explaining a liquid processing method of the present invention.

[Explanation of symbols]

1. Spin chuck, 2. Rotary shaft, 3. Wafer,
4: stripping liquid supply nozzle, 5: resist liquid supply nozzle, 6
... Edge rinse liquid supply nozzle.

Claims (2)

[Claims] 1. A method for supplying a processing liquid to a target object and performing liquid processing on the target object, the method comprising HMDS (Hexa met
hylen di silazane) forming a coating film on the surface of the object by supplying a processing liquid to the object to be processed,
Supplying a rinsing liquid to the peripheral portion of the coating film to remove the coating film at the peripheral portion, and before the step of forming the coating film, a stripping solution for HMDS removal is applied to the object to be processed. A liquid processing method, wherein the liquid is supplied to a peripheral portion. 2. The liquid processing method according to claim 1, wherein a polar solvent is used as the rinsing liquid.