JPH02278713A - Resist processor - Google Patents

Abstract

PURPOSE:To remarkably reduce dusts such as particles generate from a contact surface to be in contact with an article to be processed by making one end heavier than the other end, rotatably moving it and providing a holding piece for holding the other end only at the side face of the article to be processed. CONSTITUTION:In a processor for rotatably coating an article 1 to be processed with processing solution, supporting piece 2 is provided to support the article 1 to be processed at least at three positions, and a holding piece 22 operating to hold only the side face of the article 1 to be processed at the other end side by making one end heavier than the other end so as to rotatably move it by a centrifugal force generated by the rotation of the piece 2. Thus, the contact area to be in contact with the article to be processed is reduced to improve generation of dusts from the contact face.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a resist processing apparatus.

(Prior Art) In a semiconductor manufacturing process, there is a semiconductor manufacturing apparatus 1, for example, a resist processing apparatus.

Conventionally, this processing equipment places the central portion of the wafer in the horizontal direction on the upper surface of the spinner chuck, and then moves the wafer so that the central portion of the wafer is held integrally with the upper surface of the spinner chuck, which is in contact with the central portion of the wafer. The back side is vacuum-adsorbed. The apparatus then drops photoresist onto the center of the wafer and rotates the spinner chuck to form a photoresist film on the wafer surface.

For example, the above-mentioned device is disclosed in Japanese Utility Model Application No. 60-42730.

It is described in many publications such as Japanese Utility Model Application Publication No. 60-52622 and Japanese Utility Model Application Publication No. 60-96821.

(Problems to be Solved by the Invention) However, in the conventional resist processing apparatus, when the spinner chuck starts rotating, it is rapidly accelerated and rotates, so that slippage occurs between the spinner chuck and the wafer. This slip causes the back surface of the wafer to rub against the top surface of the spinner chuck that is in contact with the back surface, and this friction generates flakes of silicon, for example, from the wafer, or flakes of plastic, for example, from the spinner chuck.

The amount of this generation occurs in proportion to the area of contact with the back surface of the wafer. Therefore, by making the contact surface of the swinner chuck smaller, the amount of generation can be reduced, but this contact surface also has the function of maintaining the horizontal direction of the wafer, so it is possible to reduce the amount of generation. It was difficult to make it smaller than the surface.

If we ignore the effect of maintaining the horizontal direction of the wafer and make the contact surface smaller, not only will the number of times the wafer falls from the spinner chuck increase when the wafer is placed on the top surface of the spinner chuck, but also the number of times the wafer will fall from the spinner chuck will increase. During this process, the outer circumference of the wafer becomes wavy, leading to non-uniform resist processing and damage to the wafer.

The object of the present invention is to reduce the contact area that comes into contact with the object to be processed when holding the object to be processed, and to improve the generation of dust generated from this contact area. An object of the present invention is to provide a resist processing device.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a processing apparatus for spin-coating a processing liquid onto an object to be processed. A gripping piece that acts to grip only the other end or the side surface of the object to be processed by making one end heavier than the other end and rotating and moving it due to the centrifugal force generated by the rotation of the piece. It is characterized by having the following.

(effect) That is, according to the present invention, the outer periphery of the object to be processed is supported.

Furthermore, since the object to be processed is held only by the side peripheral surface and temporarily fixed by both means, the contact area can be significantly reduced compared to the conventional method for holding the center portion of the object to be processed.

The holding force can be used more effectively by holding the object at its outer periphery than by holding the center portion of the object.

Furthermore, since the gripping pieces provided at at least three locations along the outer periphery of the object to be processed grip the object using a gripping mechanism that utilizes centrifugal force, the center of the wafer and the center of rotation can be simultaneously aligned, resulting in stable operation. rotation is obtained.

(Example) An example in which the apparatus of the present invention is applied to a resist processing apparatus will be described below with reference to the drawings.

First, the structure of the resist processing bag (2) will be explained.

A spinner chuck (2) is provided on which the outer peripheral back surface of a semiconductor wafer (hereinafter abbreviated as wafer) is placed, and the side peripheral surface of the placed wafer is gripped and temporarily fixed. This spinner chuck (3) is connected with a rotational movement mechanism, for example, a drive motor (3), and when this drive motor (3) is driven, the wafer (t) is moved through the spinner chuck (2).
is rotated.

Wafer a) held by the above spinner chuck ■
17J] A cylindrical cup G) with a bottom is provided so as to be movable downward, and this cup (A) will protect the wafer even if the resist l- scatters when applying resist to the wafer 0). 0 It has a structure that does not bounce back to the surface.

In addition, a resist discharging nozzle (8) is installed so that the resist 1- can be dropped onto the wafer 0 surface from the axial center of the bipedal wafer ■.
is provided. One end of this nozzle (8) is located above the rotation axis of the wafer (2) held by the spinner chuck (2), for example, at a position approximately 20 nm above the height of the field. The supply system that supplies resist liquid to one end of ) and this nozzle is a suck back ■), an on-off valve (1
0), a supply source (12) to the register 1 via a pump (11)
).

Next, the main part of the present invention will be explained with reference to FIG. 2(a).

The spinner chuck (1) that rotates the wafer (1) of the nozzle treatment apparatus is a wafer support mechanism (13) that is provided to rotate the wafer (O) by driving the drive motor (2).
) and the wafer ( ) using the centrifugal force generated by rotation.
-) A gripping mechanism (14) provided to evenly grip a portion of the side peripheral surface.

First, as shown in FIG. 2(b), the wafer support mechanism (13) has a shaft (3a) of a drive motor installed vertically, and a rotating shaft at the end, for example, a stainless steel cylinder with a diameter of 40 np and a length of 60 m. A rotating shaft (15) of the shape is firmly fitted and connected.

On the side circumferential surface above the rotating shaft (15), there are three
strip-shaped support pieces, e.g. plate thickness 1.2mm x width 9I x length 7
0nn stainless steel support pieces (16) are provided on three sides. The lengths of the support pieces (16) provided on these three sides are set so that a diameter P2 is formed which is one size larger than the outer diameter P1 of the wafer.

The free end of this length is bent upward in the same direction as the rotation axis (15) so as to surround the wafer (1). Further, it stands upright from this bent position to a predetermined height, for example, 20 nn upward from the upper surface of the support piece (16), and is provided to protect the wafer (1) from other members.

A cushioning material 1, such as a fluororesin plate material (18), is attached to the inner surface (17) of the upright support piece (16) to prevent damage in the event of a collision with the wafer (2). .

The support piece (16) is provided with at least three studs (20) for attaching gripping members (19), which will be described later. That is, at least three gripping members (19) are provided at at least three positions at which the gripping members (19) act to grip the side peripheral surface of the wafer (0), for example, at positions at a diameter R1 from the rotation axis (15).

Even if the wafer (2) is placed on the support piece (16) and rotated, the wafer (2) will jump out because the wafer (0) is not fixed to the support piece (16).

Therefore, it is necessary to attach a gripping mechanism (14) to the stud (20) of each support piece (16) to secure the wafer α) to the support piece (16). .

The gripping mechanism (14), as shown in FIG. 2(C),
A gripping member (19) that grips at least three places on the wafer ■
are provided at equal intervals, for example, at equal intervals of 120°.

The gripping mechanism (19) is rotatably attached to a stud (20) provided on the support piece (16) via a bush (21). This rotatably attached gripping member (19
) has the stud (20) as a fulcrum, and is provided with a gripping claw (25) at one end for gripping the wafer (G), and at the other end for pressing the gripping claw (25) against the side peripheral surface of the wafer (2). A weight (26) is provided to generate and apply a pressing force.

Near the gripping claw (25), there is a mounting surface on which the wafer (2) is placed at a predetermined distance from the fulcrum, for example, a width 6
A mounting surface (24) with a length of 4mm mm (2) Size 1 For example, a plurality of step portions are formed in succession so that the outer peripheral back surface of a 4-inch wafer or a 5-inch wafer is placed thereon.

Furthermore, a cushioning material such as a fluororesin plate (25a) is provided on the gripping surface of the gripping claw (25) that comes into contact with the wafer (1) side circumferential surface to prevent damage to the wafer (1).

Further, a tension coil spring (23) is provided to return the gripping claw (25) gripping the side peripheral surface of the wafer (2) to its original position when the rotation of the wafer support mechanism (13) is stopped.

Next, the operation will be explained.

First, a handling arm (not shown) places the prealigned wafer (2) on the upper surface of the spinner chuck (4).

The drive motor 〇 is energized according to a pre-stored program, and this energization causes the spinner chuck ◯ to rotate at a low speed, for example, 20rpm, then 3Orpm, and 40rpm.
m and sequentially. Then, the wafer (2) is rotated by centrifugal force until it is gripped by the gripping claws (25).

That is, the operation of the gripping claws (25) gripping the side peripheral surface of the wafer (G) will be explained with reference to FIG.

A weight (26) provided at the opposite end of each gripping claw (25) provided at equal intervals of 120° is rotated by the drive motor (3).

For example, by rotating at 20 rpa+, a centrifugal force is applied and the material moves outward. Along with this movement, the gripping member (19)
Each gripping claw (25) provided at one end of the stud (20) rotates one turn clockwise about the fulcrum position of the stud (20). Since the side peripheral surface of the wafer (2) is positioned on the locus of this rotation, three positions on the side peripheral surface of the wafer (2) are equally gripped.

Thereafter, the spinner chuck (2) is increased to a rotational speed necessary for coating rotation, for example, 11,000 rpm.

A predetermined amount of resist is dropped from the tip of nozzle 0 disposed above the spinner chuck (1) toward the center of the wafer (2). This resist is discharged by driving a pump (11) according to a preset program.

As the motor (2) rotates, the dropped resist liquid is spread from the center to the periphery. Thereafter, the motor (2) is rotated at a high speed, for example, 4000 rpm, to dry the resist. As a result, wafer 03
This series of operations (9) for forming a uniform resist layer on the surface is repeated to process each wafer one by one. In this way, the wafer (O) is placed at at least three locations on the outer peripheral edge portion, and is further gripped and fixed.
Compared to the method of suctioning and holding the area of the center region, the contact area can be made extremely small.

Therefore, it is possible to drastically reduce the amount of dust such as particles generated from the contact surface compared to the conventional method, and the problem of defective wafers caused by these particles is alleviated. With this modification, problems such as defects in wafer circuits caused by adhesion of particles and problems such as "deviation" of focus during exposure can be improved over the past.

In the above embodiment, the gripping members (9) are provided at three locations, but the present invention is not limited to this, and there is no problem if the gripping members (9) are provided at two, four, five, six, etc. locations.

In the above embodiment, a resist processing device was provided.
The present invention is not limited to this, and can also be used in a coating device that applies a treatment liquid to an object to be treated.

(Other Embodiments) Hereinafter, other embodiments of the main parts of the device of the present invention will be described with reference to the drawings.

As shown in Figure 4(a), the main part of the device consists of a shaft (27) of a drive motor (27) installed vertically.
a) At the upper end, there are a plurality of gripping rods (29) provided in the horizontal direction for gripping the side peripheral surface of the wafer (28), and a plurality of gripping rods (29), e.g. For example, it is arranged at 72°.

” - At the upper ends of the five gripping rods (29), as shown in Fig. 4(b)
As shown in FIG. 2, gripping claws (32) are provided which abut the side circumferential surface (30) and the outer circumferential back surface (2) of the wafer (28).

A gripping ring (33) that can be rotated twice is provided in a direction perpendicular to the axial direction of the shaft (27a) so as to surround the gripping rod (29). A hollow part is provided in the center of this gripping ring (33), and the inner wall of this hollow part is connected to the gripping rod (33).
29). When this back surface is focused on the inner wall of the gripping ring (33), the gripping claws (32) are configured to evenly grip the outer peripheral surface of the wafer (28).

At this point, the gripping ring (33) may be raised; however,
The drive motor (27) provided with the gripping rod (29) may be lowered.

Next, the operation will be explained.

The wafer (28) is placed on the mounting surface of a gripping claw (32) formed one size larger than the diameter of the wafer (28).

The grip ring (33) is raised to a predetermined height by a lifting mechanism (not shown). Along with this rise, the inner wall of the bipedal gripping ring (33) comes into contact with the gripping rod (29),
This gripping rod (29) acts to focus the gripping claws (32) and grips the wafer (28). After this gripping, the 5 drive motor (27) is rotated, and the wafer (28) is gripped and rotated at 5 points on the outer periphery, so that the area of the central area of the wafer (O) is absorbed. Compared to the holding method, the contact area is extremely small, so it is possible to drastically reduce dust such as particles generated from the contact surface compared to conventional methods.
This solves the problem of wafer defects caused by these particles.

In the above embodiment, the grip ring (33) is raised to grip the side surface of the wafer (28), but the whole grip rod (29) is lowered to grip the side surface of the wafer (28). You can also hold it.

Further, the present invention can be applied to any resist treatment, including application of a developing solution and application of a cleaning solution.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the overall configuration for explaining one embodiment in which the present invention apparatus n is applied to a resist processing apparatus, and FIG.
Figure 3 is an exploded explanatory diagram to explain the structure of the spinner chuck in Figure 1. Figure 3 is an operational diagram to explain the state in which the spinner chuck in Figure 1 grips a wafer. Figure 4 is an exploded explanatory diagram to explain the structure of the spinner chuck in Figure 1. It is an explanatory view of a spinner chuck for explaining the main part of another example applied to the device. 1... Wafer 13... Wafer gripping mechanism 1
4... Gripping mechanism 15... Rotating shaft 19...
Gripping member 20... Stud 22... Gripping piece 23... Tension coil spring 24... Placement surface 25... Gripping claw 26... Weight Patent applicant Tokyo Electron Ltd. (a) Fig. b) (b) Figure (c)

Claims (1)

[Claims] In a processing apparatus for spin-coating a processing liquid onto an object to be processed, a support piece is provided to support the object to be processed at at least three places, and one end is provided so as to be rotated by a centrifugal force generated by the rotation of the support piece. 1. A resist processing apparatus comprising: a gripping piece that is made heavier on one side than the other end and rotated so that the other end side grips only the side surface of the object to be processed.