JPH09219378A - Semiconductor manufacturing equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent foreign matters from entering a wafer by locating holder sections to hold the wafer at a place away from a disc face. SOLUTION: On the periphery of a disc 7 of an ion implanter, many holder sections 8 for holding a wafer are placed. The holder sections 8 are projecting from the face of the disc 7 and each of the holder sections 8 has a clamp ring 9 for holding the wafer. When the ion beam is cast on the wafer from the direction at right angles with the wafer held by the holder sections 8, the ion beam hits a part of the surface of the disc 7 near the outside of the wafer. Therefore, even if foreign matters such as ions of different kinds are sputtered, they do not reach the wafer located at a high position and fall below the holder sections 8. Therefore, the foreign matters never enter the wafer and the characteristics of the products after ion implantation can be kept good. Furthermore, the dust which floats on the surface of the wafer, can be reduced.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a semiconductor device. More specifically, the present invention relates to an ion implantation apparatus used for impurity doping in a semiconductor manufacturing process, and more particularly, to an improvement of a disk having a holder portion that holds a large number of wafers.

[0002]

2. Description of the Related Art In an ion implantation apparatus used for forming a semiconductor diffusion layer, a plurality of wafers are supported on a disk and set in an ion implantation chamber.

FIG. 5 is a perspective view showing the external appearance of a conventional disk installed in the ion implantation chamber. This disc has a holder portion 8 for holding a large number of wafers at the peripheral portion on the surface thereof. Each holder part 8 is provided with a clamp ring 9 for holding a wafer. The clamp ring 9 has a structure in which a plurality of pressing claws are arranged in a ring shape, and fixes and holds the wafer from the peripheral side surface of the wafer.

During the ion implantation process, the disk having the above structure is placed in the implantation chamber while being kept in a vertical posture (a posture perpendicular to the ion irradiation direction) in order to apply the ion beam to the wafer, and before and after the treatment. In order to set the wafer in the holder part 8 or take out the wafer from the holder part 8, the wafer is put in and taken out from the implantation chamber in a horizontal posture.

[0005]

However, according to the above-mentioned conventional disk for supporting the wafer, the wafer is set on the holder portion provided on the same surface as the disk surface, so that the ion beam implantation into the wafer is performed. At this time, foreign matter on the outside of the wafer mixes and adheres to the wafer, which adversely affects the characteristics of the product.

FIG. 6 is a diagram for explaining the reason why the foreign matter is mixed and adhered to the wafer.

As shown in this figure, the wafer 6 on the disk 7
When the ion beam is implanted in a direction perpendicular to the disk 6, the ion beam hitting the surface of the disk 7 in the vicinity of the outer side of the wafer 6 causes the disk material and foreign ions remaining attached to the surface of the disk 7 during the previous ion implantation. The foreign matter 10 is sputtered, and the foreign matter 10 is mixed into the wafer 6 as shown by the arrow.

Further, according to the above-mentioned conventional disk, the tilt angle adjustment (adjustment of the angle of the ion beam implantation surface of each wafer with respect to the ion beam direction) for avoiding the channeling effect and the shadow effect is performed by the ion implantation process. Then, the disk 7 itself is inclined, or the ion implantation process is interrupted, the disk 7 is changed from the vertical posture to the horizontal posture, and the wafer 6 to be ion-implanted from the implantation chamber is rotated by, for example, 180 °. After that, the disk 7 was put into the driving chamber again and the horizontal position was changed to the vertical position.
Therefore, the end station part in the driving chamber where the disk 7 is installed is upsized. Further, when changing the orientation or posture of the wafer, the ion implantation process must be interrupted and the disk must be taken in and out, which increases the ion implantation process time and reduces the yield.

Here, the channeling effect means that, when ions are injected into a crystal, an ion beam is incident parallel to the axis of a so-called channel surrounded by the crystal atoms and reaches a deep position without colliding with the crystal atoms. The effect of entering. Further, the shadow effect means that the resist film in the pattern step portion serves as a wall to block the ion beam when ions are implanted into a portion of the wafer on which the resist pattern is formed without the resist film.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and it is possible to prevent foreign matter from entering the wafer.
An object of the present invention is to provide a semiconductor manufacturing apparatus such as an ion implantation apparatus capable of obtaining a high quality product and further improving the yield.

[0011]

To achieve the above object, in the present invention, in a semiconductor manufacturing apparatus provided with a support plate having a plurality of wafer holder parts, each wafer holder part is placed on the support plate surface. Provided is a semiconductor manufacturing apparatus, which is provided so as to project.

According to the above construction, since the holder for holding the wafer is provided at a position higher than the disk surface (support plate surface), when the ion beam is injected into the wafer, the disk surface near the outside of the wafer is subjected to the ion beam irradiation. Even when the foreign matter is hit and the foreign matter is sputtered, the foreign matter does not mix and adhere to the wafer, and good product characteristics can be maintained.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment,
It is characterized in that the angle of the wafer mounting surface of each wafer holder is adjustable.

Another preferred embodiment is characterized in that each of the wafer holders is detachably attached to the support plate.

Furthermore, another preferred embodiment is characterized in that the support plate is configured to be able to move in and out in the posture of the processing state.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a basic configuration diagram of an ion implantation apparatus to which the present invention is applied. This ion implanter comprises an ion source 1, a mass analyzer 2, an accelerator 3, a beam scanner 4 and an implantation chamber 5. A wafer 6 to be ion-implanted is set in the implantation chamber 5. In the ion implanter having the above-described configuration, the gaseous source impurities are ionized, the mass analyzer 2 separates the ions of the element to be implanted, and the ions are accelerated by the electric field of the accelerator 3 and the beam scanner 4 is used. Then, the wafer is deflected in a desired direction and injected into a predetermined portion of the wafer 6 in the implantation chamber 5. In the implantation chamber 5, a plurality of wafers 6 are supported on the disc.

FIG. 2 is a perspective view showing the outer appearance of the disk of the ion implantation apparatus according to the present invention. This disk 7
The ion implantation apparatus shown in FIG. 1 is clamped at the end station portion in the implantation chamber 5 and installed vertically.

A holder portion 8 for holding a large number of wafers is arranged on the peripheral portion of the disc, and the holder portion 8 is provided so as to project from the surface of the disc 7. A clamp ring 9 having the same structure as that of the conventional example shown in FIG. 5 is provided on each holder portion 8 for holding the wafer.

FIG. 3 shows a holder portion 8 of the disk 7 shown in FIG.
It is explanatory drawing at the time of implanting an ion beam into the wafer hold | maintained at.

As shown in this figure, when the ion beam is implanted from the direction perpendicular to the wafer 6, the ion beam hits the disk surface near the outside of the wafer 6, and the disk material and the surface of the disk during the past ion implantation. Even if the foreign matter 10 such as foreign ions, which is still attached to the wafer, is sputtered, the foreign matter 10 holds the wafer 6 in the holder portion 8.
Is higher than the surface of the disk, it does not reach the wafer 6 and falls below the holder portion 8. Therefore, the foreign matter 10 does not mix into the wafer 6, and the characteristics of the product after ion implantation can be kept good. Further, dust floating on the wafer surface can be reduced, and characteristic deterioration due to dust adhesion can be prevented.

FIG. 4 is a schematic configuration diagram of a disk in which each holder portion for holding a wafer is configured such that its tilt angle and rotation angle can be freely changed by using a universal joint or the like.

As shown in this figure, if each holder 8 is constructed so that the tilt angle can be adjusted as shown by the dotted line, the disc itself can be avoided in order to avoid the channeling effect and the shadow effect as in the conventional disc. Need not be tilted, and there is no need to insert or remove the disc or change the posture of the disc, and it is sufficient to adjust each holder portion 8 individually.

Therefore, unlike the conventional disk, it is not necessary to enlarge the end station portion for clamping the disk, the disk can be made compact, and the ion implantation processing does not have to be interrupted each time the angle of the wafer is changed. The time can be shortened and the yield can be improved.

Further, by adopting the disc structure as shown in FIG. 4, the disc can be put in and taken out in the vertical posture, and the whole device can be put in and out as compared with the conventional disc which is put in and put out by changing the vertical posture to the horizontal posture. The size of can be reduced, and space can be saved.

Furthermore, if the holders of the disk shown in FIG. 2 or 4 are made detachable, the size of the wafer can be changed. Further, wafers of different sizes can be processed at the same time, and the processing can be easily performed by changing the angle or the like for each wafer.

[0026]

As described above, in the present invention, since the holder portion for holding the wafer is provided at a position distant from the disk surface, foreign matter due to the hitting of the ion beam does not reach the wafer. It is possible to prevent foreign matter from entering the wafer, obtain a high-quality product, and reduce dust.

Further, in order to avoid the channeling effect and the shadow effect, if the tilt angle of the holder portion is adjustable, it is not necessary to insert or remove the disc for adjusting the angle, and the time required for the disc to be inserted or removed is reduced. It can be omitted, and the end station portion for clamping the disk can be downsized and the yield can be improved.

Further, if each holder of the disk is detachable, it is possible to deal with the change of the wafer size. Further, if the disc can be freely moved in and out in a vertical state, the entire apparatus can be downsized.

The present invention is not limited to the ion implantation apparatus,
It is also applicable to semiconductor manufacturing equipment such as ion etching equipment and sputtering equipment.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of an ion implantation device.

FIG. 2 is a perspective view showing an outer appearance of a disk of the ion implantation device according to the present invention.

FIG. 3 is an explanatory diagram when implanting an ion beam into a wafer held by a holder portion of the disk of FIG.

FIG. 4 is a schematic configuration diagram showing another example of the holder portion of the disc according to the present invention.

FIG. 5 is a perspective view showing an external appearance of a disk of a conventional ion implantation device.

FIG. 6 is an explanatory diagram when implanting an ion beam into a wafer held by a holder portion of the disk of FIG.

[Explanation of Codes] 1: Ion source, 2: Mass analyzer, 3: Accelerator, 4: Beam scanner, 5: Implanting chamber, 6: Wafer, 7: Disc,
8: Holder part, 9: Clamp ring, 10: Foreign matter.

Claims (4)

[Claims] 1. A semiconductor manufacturing apparatus provided with a support plate having a plurality of wafer holder parts, wherein each of the wafer holder parts is provided so as to project from the surface of the support plate. 2. The semiconductor manufacturing apparatus according to claim 1, wherein the angle of the wafer mounting surface of each wafer holder is adjustable. 3. The wafer holder unit is configured to be detachable from the support plate.
4. The semiconductor manufacturing apparatus according to claim 1. 4. The semiconductor manufacturing apparatus according to claim 1, wherein the support plate is configured so that it can be moved in and out in a posture of a wafer processing state.