JPH0193122A - Centrifugal rotary machine for wafer for developing resist - Google Patents

Abstract

PURPOSE:To thoroughly remove any residual resist by giving centrifugal force in the normal direction of wafers coated with resist. CONSTITUTION:The normals passing through the center of wafers fixed to wafer containers 12 are orthogonal to the rotary central axes of a centrifugal rotary machine 13. When the rotary machine with wafers fixed to the containers thereof is rotated to attain the specified speed, a developer is injected from a pressure injecting tubes 14 into the containers 12. The developer passing through the gaps between the periphery of wafers and the inner wall of a cylindrical part fills in the recession of a solution reservoir. Through these procedures, the wafers are immersed in the developer while the surfaces of the wafers coated with the resist face toward outside so that the centrifugal force by the centrifugal rotation is given to remove the resist molecules liberated from the inside of developing pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wafer centrifugal rotating machine for resist development used in the manufacture of semiconductors.

[Conventional technology]

Wafers for semiconductor manufacturing are spin-coded with a resist, and a pattern is exposed on the resist using light, electrons, ion beams, or X-rays.

Next, by developing the exposed resist,
Depending on the type of resist used, the exposed areas are removed or left behind. After unnecessary resist is removed, various other manufacturing steps are performed. Through these many steps, a VLSI device is finally manufactured.

On the production line, the resist is developed by being fixed by suction on the back surface of the wafer and rotating horizontally around the central axis of a fixture. At this time, the developer is sprayed onto the surface of the resist. The wafer is rotated slowly to agitate the developer on the resist surface and quickly to remove the developer.

[Problem that the invention seeks to solve]

A problem inherent in the method of developing resist by rotating the wafer axis using a wafer rotating machine is that undeveloped resist or components of the resist remain on the wafer surface after development. Therefore, this axial rotation method appears to violate ideal conditions for best resist development. For example, when developing submicron contact holes,
It appears that resist molecules liberated from the resist by the developer tend to remain inside the contact hole being developed due to the attractive and centrifugal forces inherent in the axial rotation method. The resist and resist components remain inside the contact hole, which prevents the developer from entering and also prevents the release of many resist molecules. Centrifugal forces perpendicular to the direction of development do not completely remove resist components and spent developer from the contact hole, pushing these materials against the walls of the contact hole. Therefore, in conventional development using a wafer rotating machine, there is a problem in that resist residue or "scum" must be removed later by exposure to deep ultraviolet light or heating.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wafer centrifugal rotating machine for resist development that can solve these problems and completely remove resist residue.

[Means for solving problems]

The present invention is a wafer centrifugal rotator for resist development that develops exposed resist on a semiconductor wafer, and the wafer coated with resist is rotated so that the normal line at the center of the wafer is perpendicular to the central axis of rotation of the centrifugal rotator. The present invention is characterized in that it includes a wafer container that can be fixed inside the wafer container, and a liquid injection tube that can inject at least a container developer into the inside of the wafer container.

[Effect]

The wafer centrifugal rotating machine for resist development of the present invention centrifugally rotates the wafer so that the normal line at the center of the wafer is perpendicular to the central axis of rotation of the centrifugal rotating machine.

At this time, the surface of the wafer coated with resist faces outward, ie, in the direction of centrifugal force.

The centrifugal force inherent in this centrifugal rotation method acts to remove ``loose resist molecules and used developer from the interior of the developed pattern. Development is more complete because the resist components are removed perpendicular to the wafer surface, rather than parallel to the wafer surface as in conventional axial rotation methods.

〔Example〕

Embodiments of the present invention will be described based on the drawings.

FIG. 3 is a diagram showing a liquid reservoir 1, which is a member constituting a wafer container, and in which wafers are developed.

(a) is a plan view, (b) is a front view, (C) is a side view, (
d) is a bottom view.

This liquid reservoir 1 is integrally formed with a cylindrical portion 2 and a cylindrical portion 3 having an outer diameter slightly larger than the outer diameter of the cylindrical portion 2. An opening 4 for loading and unloading wafers is formed in the semicircumferential portion of the cylindrical portion 2 on the side that contacts the cylindrical portion 3.

Five wafer holders 5 are provided on the inner wall of the end of the cylindrical portion of the other semicircumferential portion. The wafer holder has a gap into which the peripheral edge of the wafer can be inserted.

The cylindrical part 3 has a conical recess 6 that opens toward the cylindrical part 2.
A liquid discharge pipe 7 is connected to the bottom of this recess. Further, an electromagnetic pulp 8 for opening and closing the liquid discharge pipe 7 is provided at the bottom of the liquid reservoir 1.

O-rings 9 are fitted into the stepped portions of the outer walls of the cylindrical portion 2 and the cylindrical portion 3 of the liquid reservoir 1. In addition, 'M3 figure (
In b) and (c), 0 is used to make the drawings clearer.
The ring is shown in cross section.

FIG. 4 is a diagram showing the annular body 10 that is slidably fitted into the cylindrical portion 2 of the liquid reservoir 1 having the above-described configuration. (a) is a plan view, (b) is a front view, and (C) is a side view. In addition, in FIGS. 4(b) and 4(c), the liquid reservoir 1 is shown by dotted lines in order to make it easier to understand the fitted state with the liquid reservoir 1.

Five small blocks 11 are provided on the inner wall of the cylindrical end of the annular body 10 at a semicircumferential portion facing the opening 4. These protrusions project into the opening 4.

A wafer container is constituted by the liquid reservoir 1 and the annular body 10 having the above-described structure.

FIG. 1 is a plan view of a resist developing wafer centrifugal rotary machine 13 in which eight wafer containers 12 are arranged at equal intervals on a circumference centered on the central axis of rotation of the centrifugal rotary machine.

Note that FIG. 1 shows a state in which the annular body 10 is shifted in the opposite direction to the columnar part 3 and the opening 4 is exposed.

Further, the O-ring 9 is shown in cross section for clarity of drawing.

The wafer container 12 is arranged so that the opening 4 faces upward, the cylindrical part 3 is arranged outward from the rotation center of the centrifugal rotating machine, and the central axis of the wafer container 12 is arranged so that the central axis of the wafer container 12 faces upward. It is arranged perpendicular to the rotation center axis of the rotating machine.

A pressurized injection tube 14 is provided in the center of the centrifugal rotary machine and extends radially into each wafer container 12 .

A developing solution or a cleaning solution is injected into the wafer container from this pressurized injection pipe 14.

Next, the operation of this embodiment will be explained.

The resist-coated and exposed wafer is inserted into the wafer container 12 through the opening 4 with the resist-coated side facing the recess 6, and the half-periphery of the wafer is inserted into the gap in the wafer holding part 5. to hold the wafer. Thereafter, as shown in FIG.
and press it against the O-ring 9. As a result, the opening 4 is closed by the annular body 10. Also, at this time, a plurality of processors 11 provided on the inner wall of the annular body 10 are attached to the wafer held by the wafer holding section 5.
The wafer slides into contact with the half-periphery on the opposite side to the half-periphery of the wafer, and together with the holding by the wafer holder 5, fixes the wafer. As described above, the annular body 10 is pressed against the O-ring 9 in order to maintain a seal against liquid and prevent the liquid from leaking out of the wafer container.

The normal line passing through the center of the wafer mounted in the wafer container 12 as described above is perpendicular to the rotation center axis of the centrifugal rotating machine.

Now, after fixing the wafer in the wafer container 12 as described above, the electromagnetic pulp 8 is closed and the centrifugal rotating machine is rotated. When the centrifugal rotating machine reaches a predetermined speed, developer is injected into the way/S container 12 from the pressurized injection pipe 14. The developer passes through the gap between the peripheral edge of Ueno\ and the inner wall of the cylindrical portion 2, enters the recess 6 of the liquid reservoir 1, and completely fills at least the recess 6 with the developer. As a result, the wafer /'' is immersed in the developing solution. Since the surface of the wafer coated with resist faces outward, the centrifugal force due to centrifugal rotation is applied to the loose resist molecules from inside the developed pattern. In this case, the resist molecules are removed in a direction perpendicular to the wafer surface, so the development is complete. After a predetermined development time, the electromagnetic pulp 8 is opened and the liquid is removed. The developer is discharged from the reservoir 1 through the liquid discharge pipe 7. At this time, centrifugal force acts to remove the used developer from inside the development pattern.

After development, cleaning of the wafer is performed by injecting a cleaning liquid from the pressurized injection tube 14 in the same way as injecting the developer.

According to the wafer centrifugal rotation machine for resist development of this embodiment, by adjusting the injection and discharge of the developer and cleaning solution, it is possible to combine timed-release/constant flow and development/cleaning cycles. .

〔Effect of the invention〕

As explained above, according to the wafer centrifugal rotation machine for resist development of the present invention, since centrifugal force acts in the normal direction of the wafer coated with resist, it is not possible to completely remove the resist and resist components. It becomes possible. Therefore, the conventional process of removing resist residue using deep ultraviolet rays becomes unnecessary.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a wafer centrifugal rotating machine for resist development which is an embodiment of the present invention, Fig. 2 is a plan view of the annular body pressed against the O-ring in Fig. 1, and Fig. 3 is a wafer container. FIG. 4 is a diagram showing a liquid reservoir constituting a wafer container. FIG. 1...Liquid reservoir 2...Cylindrical part 3...Cylindrical part 4...Opening part 5...Wafer holding part 6... Conical recess 7...Liquid discharge pipe 8...Electromagnetic pulp 9...0 ring 10...Annular body 11...Block 12...Wafer Container 13... Wafer centrifugal rotating machine for resist development 14... Pressurized injection pipe Agent Patent attorney Yoshiyuki Iwasa 13 Centrifugal rotating machine Figure 1 Figure 2 (a) (b) (C )(a) Figure 4

Claims (2)

[Claims] (1) A wafer centrifugal rotating machine for resist development that develops exposed resist on a semiconductor wafer, in which the wafer coated with resist is processed so that the normal line at the center of the wafer is orthogonal to the central axis of rotation of the centrifugal rotating machine. 1. A wafer centrifugal rotating machine for resist development, comprising: a wafer container that can be fixed inside the wafer container; and a liquid injection tube that can inject at least a developer into the wafer container. (2) In the wafer centrifugal rotation machine for resist development according to claim 1, the wafer container stores the developer injected from the liquid injection tube and has an opening through which the wafer can be taken in and taken out; a liquid reservoir having a wafer holder that holds a part of the periphery of the wafer; and a wafer holder that is slidably fitted into the liquid reservoir and that is different from the part held by the wafer holder. an annular body having a block for fixing a part of the aperture and having a function of exposing or covering the opening by sliding; and an annular body provided at a contact portion between the liquid reservoir and the annular body to prevent liquid leakage. A wafer centrifugal rotating machine for resist development, comprising a sealing member for sealing and a pulp provided at a liquid outlet of the liquid reservoir.