JP2998259B2 - Disk holding device and disk processing method using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin disk such as a semiconductor wafer, a magnetic hard disk, an optical disk, a magneto-optical disk, a glass substrate for a liquid crystal or a photomask. Are held horizontally one by one sequentially, and while rotating the disk, the required surface treatment liquid is supplied to the surface of the disk,
Alternatively, the present invention relates to a disk holding device for performing a surface treatment such as water washing and a disk processing method using the same.

[0002]

2. Description of the Related Art For example, an apparatus for processing a semiconductor wafer (hereinafter simply referred to as a "wafer") will be described as an example of a disk. A large number of wafers were held in a holder and immersed in a processing tank containing a chemical solution to perform batch processing.If the back surface of the wafers was contaminated with dust, metal, or organic matter, In many cases, a chemical solution serves as a medium and contaminates a mirror surface of an adjacent wafer. Such contamination has an adverse effect on microfabrication of integrated patterns in order to increase the integration density of integrated circuits, and disadvantages arise in that the wafer holder becomes larger as the area of the wafer increases. .

[0003] In view of the above, in recent years, single wafer processing has been performed for cleaning wafers. A typical example of a wafer processing apparatus that performs this single-wafer processing is shown in FIG.
There is a device as shown in FIG. This wafer processing equipment
A method is employed in which a silicon wafer or the like is treated with a chemical solution or washed with pure water, and the wafer is dried by rotating the wafer. In order to briefly describe this wafer processing method, a processing method in which a wafer is washed with pure water and dried by rotating the wafer will be described as an example. The wafer processing method used will be described.

In FIG. 5, this wafer holding device comprises:
It mainly comprises a holding mechanism 1 for holding and fixing the wafer 3, a motor 2 for rotating the holding mechanism 1, nozzles 4a and 4b for supplying pure water, and a cover 5. The holding mechanism 1 has three movable claws 1a, 1b and 1c arranged and configured so as to be able to hold the outer periphery of the wafer 3 at equal angular intervals of 120 °. 7. The movable claws 1a, 1b in the diameter direction up to the position of the broken line shown in FIG.
When only the movable claw 1a is shown in FIG. 7 and the movable claw 1a is slightly opened, and the wafer 3 is held, the movable claw 1a, 1b and 1c are diametrically moved to the position indicated by the solid line in FIG. A mechanism that moves and closes the movable claw 1a, 1b, and 1c so that the outer periphery of the wafer 3 is in point contact with the movable claw 1a, 1b, and 1c, and that a step portion 10 formed inside them holds three very small outer peripheral surfaces of the wafer 3. Is configured.

The wafer 3 is carried by the arm (not shown) onto the holding mechanism 1 when the gate valve 6 is opened, and the movable claws 1a and 1b of the holding mechanism 1 shown in FIGS. The wafer 3 is held by closing 1c from the open state. By rotating the holding mechanism 1 with the motor 2 while holding the wafer 3 and injecting pure water from the nozzles 4a and 4b, the front and back surfaces of the wafer 3 are cleaned. The washed water is sequentially discharged from the drain 8. After the cleaning, the supply of pure water is stopped, and the holding mechanism 1 is rotated by the motor 2 at 3000 rpm. Water adhering to the front surface and the back surface of the wafer 3 can be removed by centrifugal force and dried. Thereafter, the rotation of the motor 2 is stopped, the gate valve 7 is opened, and the wafer 3 is transported out of the cover 5 by an arm (not shown).
Various wafer holding apparatuses for such single-wafer processing have been proposed. For example, JP-A-63-153839
The principle described above is disclosed in "Rotation holding device for substrate".

[0006]

However, in such a wafer holding device, the wafer 3 is moved around the outer periphery thereof.
Water is not sufficiently dried by drying by rotation of the motor 2 because the water is held in several places. After cleaning with pure water, the wafer 3 is rotated at 3000 rpm for 120 seconds,
Even after the drying process, as shown in FIG. 8, although the movable claws 1a, 1b, and 1c of the holding mechanism 1 are slight, the water after the cleaning remains at the positions 11a, 11b, and 11c that have been in contact with the wafer 3. This water causes a watermark, which is a quality defect of the wafer 3. These positions 1
To completely remove the water remaining in 1a, 11b and 11c, it is possible to perform a process of rotating the wafer 3 at 3000 rpm for about 600 seconds, but there is a problem that the throughput is significantly reduced.

[0007]

In a single-wafer type disk holding device, two or more sets of holding mechanisms for holding the outer periphery of a disk with three or more movable claws are provided. By arranging them at different positions and alternately opening and closing different sets of movable claws to switch the holding position on the outer periphery of the disk, rotating the disk to dry the liquid adhering to the disk The above problem was solved.

[0008]

Therefore, if the configuration of the disk holding device of the present invention is adopted, it is possible to eliminate a place on the disk that has not reacted with the chemical solution, a place that has not been washed with water, and a place that has not been dried.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram for explaining the principle of a first embodiment of a holding mechanism of a wafer holding apparatus according to the present invention, and FIG. 2 is a plan view showing a mechanism for implementing the principle. FIG.
A is a partially enlarged perspective view of a movable claw of the holding mechanism, and FIG. B is a partially enlarged side view for explaining a dimensional relationship of components of the movable claw of the holding mechanism. FIG. 4 is a schematic diagram for explaining the principle of the second embodiment of the holding mechanism of the disk processing apparatus of the present invention.

First, the holding mechanism of the wafer holding device of the present invention will be described with reference to FIGS. Since other configurations of the disk processing apparatus of the present invention are the same as those of the conventional configuration shown in FIG. 4, the same components are denoted by the same reference numerals. In FIG. 1, three pairs of movable claws 12a, 1a, 1b, and 1c are further provided in the present invention.
The feature is that 2b and 12c are additionally arranged with a shift of 60 °. The movable claw 12 additionally arranged as described above
As shown in FIG. 2, a, 12b and 12c are configured to be movable in the diametrical direction of the holding mechanism 1, but only a very small distance, similarly to the conventional movable claws 1a, 1b and 1c. The movable claw 1 is provided by an arm 14a of a "U" shape which is rotatably supported near the outer periphery of the internal rotating member 13.
a and 12a are interconnected. Both arms of the arm 14a have the same length. Reference numerals 15 and 16 are support portions for the movable claws 1a and 12a of the arm 14a, respectively, and reference numeral 17 is a rotation fulcrum 17 of the arm 14a. Similarly, the other two pairs of movable claws 1b and 12b, 1c and 12
The "c-shaped" arms 14c and 14c are also linked to c.

The operation of the holding mechanism 1 will be described with reference to FIG. The wafer 3 is brought to the holding mechanism 1 by an arm (not shown), and first, a pair of movable claws 1a, 1b
And 1c. When the wafer 3 held by the holding mechanism 1 is rotated by the motor 2, pure water is supplied from the nozzles 4a and 4b to wash the wafer 3, and after a predetermined time has elapsed, the supply of pure water is stopped. Then, the internal rotating member 13 is slightly rotated in the direction of arrow X. Then, the movable claws 1a, 1b and 1c move away from the edge of the wafer 3, and almost simultaneously with another set of movable claws 12a.
a, 12b and 12c are the movable claws 1a, 1
The edges at positions different from the positions held by b and 1c are held and fixed. Then, pure water is supplied again from the nozzles 4a and 4b to wash the wafer 3. Thus, wafer 3
By moving the edges of the movable claws 1a, 1b first.
And the edge portion of the wafer 3 held by 1c is also cleaned.

After washing for a predetermined time, the supply of water is stopped, and the wafer 3 is continuously rotated while being held by the movable claws 12a, 12b and 12c, whereby the water is scattered by centrifugal force and can be dried. Where the movable claws 12a, 12b and 12
Since water remains between c and the edge of the wafer 3 and those portions cannot be sufficiently dried, the internal rotating member 13 is then rotated in the direction of arrow Y, and Almost simultaneously with releasing the movable claws 12a, 12b and 12c, the movable claws 1a, 1b and 1c cause the movable claws 12a, 1b and 1c to move.
When the edge of the wafer 3 at a position different from the positions 2b and 12c is held and fixed, and the wafer 3 is rotated again, the remaining water can be dried. Although it is these drying processing times, the movable claws 12a, 12b and 12
3000 rpm when the wafer 3 is being held in step c.
m for about 120 seconds, and in the state of holding the movable claws 1a, 1b and 1c while holding them, it was possible to dry at 3000 rpm for about 5 seconds.

Each of the movable claws 1a, 1b, 1c, 12
a, 12b and 12c are integrally formed at the tip of the movable plate 20 which slightly moves horizontally in the diameter direction of the arrow X as shown in a partially enlarged manner in FIG. It comprises a horizontal wafer receiving portion 10 for receiving the same and wedge-shaped pressing claws 21 sandwiching the edge thereof. The edges of these wedge-shaped pressing claws 21 are formed perpendicular to the horizontal plane of the wafer receiving portion 10. It is preferable that the area of the wafer receiving portion 10 is as small as possible. However, as shown in FIG. 3B, the horizontal length L of the wafer receiving portion 10 in the direction of the arrow X is such that the wafer 3 does not fall off even when the movable plate 20 moves in the direction of the arrow X. Must be designed in advance. That is, assuming that the stroke of the movable plate 20 is S,
The length L of the wafer receiving portion 10 is determined by the relationship represented by [Equation 1]. The position of the movable claw indicated by a solid line in FIG. 3B indicates a state where the movable claw has moved to the maximum and opened.

[0014]

(Equation 1)

FIG. 4 shows the principle of a second embodiment of the holding mechanism of the disk holding device according to the present invention. Movable claw 13
a, 13b and 13c are movable claws 12 in both structure and configuration.
a, 12b and 12c, but with a different arrangement,
This is an example in which the movable claws 1a, 1b, and 1c are arranged adjacent to each other. The switching operation of the holding positions of the movable claws 1a, 1b, and 1c and the movable claws 13a, 13b, and 13c with respect to the wafer 3 is the same as in the first embodiment.
The description is omitted.

[0016]

As described above, the wafer holding apparatus according to the present invention can eliminate the places on the wafer surface that have not reacted with the chemical solution, the places that have not been washed with water, and the places that have not been dried during wafer processing. Since the generation of the watermark can be prevented, the quality of the wafer can be improved. Further, since the decrease in throughput can be suppressed, there is an effect that the operation rate of the apparatus can be improved.

[Brief description of the drawings]

FIG. 1 is a first view of a holding mechanism of a wafer holding device of the present invention.
FIG. 7 is a schematic diagram for explaining the principle of the embodiment of FIG.

FIG. 2 is a plan view illustrating a mechanism embodying the principle shown in FIG. 1;

FIGS. 3A and 3B are partially enlarged views of a movable claw of a holding mechanism used in the present invention. FIG. 3A is a perspective view, and FIG. 3B is a side view for explaining dimensional relationships of components of the movable claw.

FIG. 4 shows a second example of the holding mechanism of the wafer holding device of the present invention.
FIG. 7 is a schematic diagram for explaining the principle of the embodiment of FIG.

FIG. 5 is a schematic diagram illustrating a configuration of a conventional wafer holding device.

FIG. 6 is an explanatory view showing an arrangement of a movable claw, which is a component of the holding mechanism shown in FIG.

7 is a conceptual diagram of the configuration of the movable claw of FIG. 6, where a solid line indicates a state where the edge of the wafer is held and fixed, and a dotted line indicates a state where the edge of the wafer is separated.

FIG. 8 is a diagram showing a watermark remaining when a wafer is processed by a movable claw of a conventional wafer holding device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Holding mechanism 1a Movable claw 1b Movable claw 1c Movable claw 2 Motor 3 Wafer 4a Nozzle 4b Nozzle 5 Cover 6 Gate valve 7 Gate valve 8 Drainage port 10 Wafer receiving part 11a Position 11b Position 11c Position 12a Movable claw 12c Movable claw 12c DESCRIPTION OF SYMBOLS 13 Internal rotation member 14a Arm 14b Arm 14c Arm 15 Supporting part 16 Supporting part 17 Rotating fulcrum 20 Movable plate 21 Wedge-shaped holding claw

Claims (3)

(57) [Claims] In a single-wafer type disk processing apparatus, two or more sets of holding mechanisms for holding the outer periphery of a disk with three or more movable claws are provided at different positions on the outer periphery when the movable claws are open. The disk holding device is arranged such that the holding positions on the outer periphery of the disk are switched by alternately opening and closing the different sets of movable claws. 2. The disk holding device according to claim 1, wherein the different sets of movable claws are switched at least twice to hold the outer periphery of the disk at a different position while holding the disk with a chemical solution. A method for processing a disk, comprising processing or washing with water. 3. The liquid adhering to the disk is dried by rotating the holding mechanism while holding the outer periphery of the disk by the movable claw of the disk holding device according to claim 1. A disk processing method, wherein the outer peripheral holding position of the disk is switched by switching to the set of movable claws, and the disk is dried.