JPS6137622A - Material transporting device using air stream - Google Patents

Abstract

PURPOSE:To transport plate material without causing damage by allowing the high pressure gas, introduced from a gas feed line, to jet out of a plurality of discharge ports formed in a guide passage partition wall, leading it from the side face of the plate to its rear surface, putting the plate afloat and by inclining the other discharge ports to the transport direction. CONSTITUTION:The body of this transport device is divided into an upper chamber as gas feed line 11 and a lower chamber as material transport guide passage 12 by parting the inside of the exterior wall in flat rectangular parallelepiped into havlves with a partition wall 10. Gas is allowed to jet out of at least one of the gas discharge ports 20 in said partition wall 10, which is situated in the neighborhood of a material carry-in opening 21, and is led from the side face of the material 2 to its rear surface, and an inclination is provided so that the material 2 gets afloat. The rest of the transport discharge ports 20b are inclined to an angle theta so as to form the gas stream in the A direction. As a result, the material 2 is put afloat by the negative pressure on the front face of material, produced by the air stream jetting out of the ports 20b, and the air stream led from the port 20a to the inclined surface of the material 2, and is transported at a high speed in contactless state.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sample transport device using an air current, and in particular to a sample transport device using an air current suitable for transporting five semiconductor wafers to the outside from a susceptor or the like of a vapor phase growth device. Regarding a conveyance device.

[Conventional technology]

With the advancement of high-density and high-integration technology for semiconductor devices, it has become extremely important to minimize damage and contamination to semiconductor wafers during THS manufacturing in order to prevent yields from decreasing. Therefore, when transporting semiconductor wafers, a transport device that does not damage or contaminate the wafers is required.

Various types of sample transport devices for transporting samples such as semiconductor wafers have been known in the past.
For example, a device suitable for picking up a semiconductor wafer placed on a wafer mounting table, so-called a susceptor, of a vapor phase growth apparatus and transporting it to a predetermined position outside is not well known.

If the conveyance distance is short, the semiconductor wafer on the above-mentioned septum is held and picked up by a vacuum tweezers or mechanical chuck device (so-called pink-up), and then Conventionally, wafers are transferred within the movement range of the pink-up head, but a recess (so-called counterbore) for storing the wafer is formed in the susceptor, and the conductor wafer is placed in the recess. If the semiconductor wafer is inserted with a small gap left, the tip of the vacuum tweezers, the claw of the mechanical chuck, etc. will not fit into the gap, and the semiconductor wafer may not be able to be picked up. Furthermore, the wafer may be damaged or cracked due to factors such as the insertion angle and the force applied to the tip, and contamination such as adhesion of fragments to the wafer surface is likely to occur.

In addition, when a vacuum chuck device or the like having a shallow spherical recess that covers the entire surface of a semiconductor wafer is used, the susceptor is formed with a recess because wafer suction cannot be performed effectively if there is even a slight gap. There is a possibility that the wafer cannot be picked up.

Note that these vacuum tweezers, mechanical chuck devices, vacuum chuck devices, etc., have a part of their pink-up head that comes into contact with the semiconductor wafer, so they are picked up and removed relatively frequently to prevent contamination. The head needs to be cleaned.

On the other hand, in the case of so-called Bernoulli tweezers, which levitate a sample such as a wafer by ejecting airflow from a nozzle, the wafer is picked up with the pink-up head section and the wafer in a non-contact state ( However, there is a risk of scattering dust etc. on surrounding wafers.

Furthermore, when conveying semiconductor wafers over relatively long distances, belt conveyors, air conveyors, etc. are used, but the operation of picking up the wafers placed on the susceptor etc. 5 This cannot be done unless a conveyance path is formed on the susceptor, etc.; in the case of a belt conveyor, the wafer and the conveyor belt come into contact with each other, which tends to cause contamination; and in the case of an air conveyor, dust etc. are scattered around the area. There is a risk of scattering.

[Problem that the invention seeks to solve]

Test As mentioned above, when using a vacuum tweezers device, mechanical chuck device, etc. as a conventional material transport device, there is a risk of damage or damage when picking up a semiconductor wafer etc. placed on the susceptor of a vapor phase growth device. Cracks are likely to occur, and contamination is likely to occur due to contact between the pickup head and the wafer, and frequent cleaning is required to prevent this. Further, these vacuum tweezers, mechanical chuck devices, vacuum chuck devices, etc. are mainly used to perform so-called sample pink-up operations, and have the disadvantage that the transport distance is relatively short. Furthermore, in the case of a belt conveyor or an air conveyor, which allows a relatively long conveyance distance, there is a drawback that pick-amplification of wafers, etc. cannot be easily performed.

Therefore, in view of the above-mentioned circumstances, the present invention not only makes it possible to levitate a sample such as a semiconductor wafer placed on a susceptor etc. without contact with a relatively simple structure, but also prevents the scattering of dust etc. in the surrounding area. It is an object of the present invention to provide a sample transport device using an air current that can transport a wafer or the like to a desired position without damaging or contaminating the wafer or the like.

[Means for Solving the Problems] In other words, the characteristics of the sample transport device using airflow according to the present invention are that a gas supply path into which high-pressure gas is introduced and a sample such as a semiconductor wafer placed under the gas supply path. A plurality of gas discharge holes are bored along the transport direction of the sample plate in the partition wall provided between the guide passage for transporting the plate, and the gas discharge holes are provided at upstream and downstream positions of the guide passage in the sample transport direction, respectively. An opening for carrying in the plate and an opening for carrying out the sample plate are opened, and at least one of the plurality of gas discharge holes is used to discharge the sample from the side of the sample plate placed at the position of the sample carrying inlet. It is formed as a pick-up discharge hole for guiding gas to the back surface to levitate the sample plate, and the other plurality of gas discharge holes have also been used in transportation to form an airflow in the same direction by tilting the sample in the same direction. It is to be formed as a discharge hole for use.

[Effect]

According to the airflow sample transport device having such a configuration, the sample plate placed stationary at the sample loading port is floated by the jet stream of gas injected from the pink amplifier discharge hole and is floated in a non-contact manner. At the same time, the gas injected from the plurality of transport discharge holes forms an air current in the sample transport direction, and due to the Bernoulli effect of this air flow, the sample plate remains in a floating non-contact state in the guide path. is transported to the sample export port.

Therefore, despite the simple configuration, a sample plate such as a semiconductor wafer placed on the susceptor of a vapor phase growth apparatus can be pinked up without contact, and transported to the desired position without contact. Furthermore, there is no need to scatter dust or the like in the surrounding area, no damage to sample plates such as wafers, and no risk of contamination.

〔Example〕

FIG. 1 is a schematic vertical cross-sectional view showing a first embodiment of the present invention. In FIG. An example of a sample transport device using airflow is shown. Further, FIG. 2 shows a sectional view taken along the line ■--■ in FIG. 1, and FIG. 3 shows a sectional view taken along the line IIT-111 in FIG. 1.

In FIGS. 1 to 3, the main body of the sample transporting device has a flat rectangular parallelepiped-shaped outer casing with a partition wall 1.
The upper chamber is divided into upper and lower halves by 0, with the upper chamber serving as a gas supply path 11 and the lower chamber serving as a guide path 12 for transporting the sample. That is,
The outer casing made of quartz glass or the like has a rectangular top plate 13 and a bottom plate 14 that are long in the sample transport direction and are horizontally arranged parallel to each other, and has a substantially flat rectangular parallelepiped shape with side plates 15.16 and end plates 17.18. It is configured so that
By horizontally arranging the partition wall 10 serving as a partition plate between the top plate 13 and the bottom plate 14, a gas supply path 11 is formed between the top plate 13 and the partition wall 10, and between the partition wall 10 and the bottom plate 14;
This guide passage 12 is formed respectively. Gas supply path 1
1, high-pressure gas is introduced through a joint pipe 19 peering into the upper plate 13, and this high-pressure gas flows into the guide passage 12 through a plurality of gas discharge holes 20 formed in the partition wall 10.
It seems to gush inside. A portion of the bottom plate 14 is cut out to form an opening 21 for carrying in the sample at an upstream position in the sample transport direction (direction of the arrow) of the guide passage 12, and an opening 21 for carrying in the sample is formed at the downstream position as well. By removing a portion of the notch, an opening 22 for carrying the sample material is formed.

Such a sample transport device main body is installed so that the opening 21 for carrying in the sample on the upstream side of the guide path 12 covers one of the semiconductor urchins/X2 placed on the susceptor 1. At this time, a large gap should not be created between the periphery of the opening 21 of the casing and the susceptor 1, so that the gas ejected into the guide passage 12 can flow outside through the gap of the periphery of the opening 21. In order to suppress leakage as much as possible, it is desirable that the shape of the peripheral edge of the opening 21 corresponds to the external shape of the reese book 1. Furthermore, a belt conveyor 23 or the like, for example, is installed in the sample transport opening 22 on the downstream side of the guide passage 12.

By the way, among the plurality of gas discharge holes 20 formed in the partition wall 10 serving as the partition plate, the opening 2 for carrying in the sample
For at least one piece provided in the vicinity of 1, the above gas is injected onto the side surface of the semiconductor sea urchin/'2 which is the sample plate,
As shown by the arrow in FIG. 4, the discharge hole Oa is formed as a pick-up discharge hole Oa for floating the wafer 2 by introducing gas to the back surface of the wafer 2. The other gas discharge holes are tilted by a predetermined angle θ in the sample conveyance direction (the direction of the arrow), and are formed as conveyance discharge holes 20b for forming an air flow in the direction of the arrow. here,
The diameter of the discharge port 20 may be, for example, 0.8 to 1.0 mm, and the above-mentioned inclination angle θ may be, for example, 20Q-300, and the discharge holes 20b for conveyance may be provided in multiple rows along the sample conveyance direction (arrow entry direction). It is being

Furthermore, in the cross section perpendicular to the sample transport direction shown in FIG. It may also be formed with Such an inclination in the width direction (direction of arrow B) is
0b, the movement of the sample plate (semiconductor wafer 2) in the width direction (direction of arrow B) being conveyed within the guide passage 12 is restricted, and the approximately central position within the guide passage 12 is held close to the sample plate. Transported smoothly.

Next, the operation of the sample transport device using such an airflow will be explained. First, as a basic operating principle, the so-called Herny effect is utilized, and as shown in FIG. As a result of the formation of an air flow or jet flow in the direction of inflow, negative pressure is created on the surface side of the semiconductor wafer 2, which is the sample plate, and the sea urchin 6'
As the wafer 2 floats up, the ejected gas flows around the back side of the wafer 2, creating a flow in the direction of the arrow, and with the balance of these airflows on the front side and the back side, the wafer 2 becomes empty. Move at high speed in the direction of the arrow while in contact. In this way, once the wafer 2 floats, it is smoothly transported in the direction indicated by the arrow. However, when floating the wafer 12 placed on the susceptor 1, it is especially important to If a recess (so-called counterbore hole) 3 is formed and the wafer 2 fits into the recess 3, the wafer 2 may not float only with the air flow (jet flow) in the direction of the arrow. be. Therefore, in the present invention, the wafer 2 is reliably levitated by blowing gas from the pink-up discharge hole 20a onto the side surface of the wafer 2 in a stationary state and forcing the gas to flow around the back surface of the wafer 2. I'm letting you do it. This pickup discharge hole 20a
By providing this, it is possible to smoothly and reliably levitate the wafer 2 which is in a stationary state. Further, the wafer 2 that has been conveyed in a non-contact state within the guide path 12 is sent to the sample carrying out opening 22, taken out to the outside through this opening 22, and placed on, for example, a belt conveyor 23. The wafers are then transported by the belt conveyor 23 to a wafer storage cassette l- (not shown) or the like.

Next, the gas supply path 11 may be formed using a tube 31, for example as in the second embodiment of the present invention shown in FIG. A plurality of gas discharge holes 20 are drilled through the pipe body 31, and the high-pressure gas introduced into the gas supply path 11 in the tube body 31 is passed through the gas discharge holes 20 into the guide path 12 for transporting the sample. All you have to do is spray it. Since the configuration of the second embodiment is the same as that of the first embodiment described above, corresponding parts in the drawings are denoted by the same reference numerals and the explanation thereof will be omitted.

In addition, the gas supply path may be formed of a cylindrical body 41 having a triangular cross section as in the third embodiment shown in FIG. 7, or a square cross section as in the fourth embodiment shown in FIG. The cylindrical body 51 may be formed with a cylindrical body 51, and the − side of these cross-sectional shapes (triangular or quadrangular) is formed by the partition wall 10, and the high pressure gas introduced into the valley gas supply path 11 is perforated in the partition wall 10. The configuration may be such that the gas is injected into the guide passage 12 through the gas discharge hole 20.

Na-j6. The present invention is not limited to the above-described embodiments; for example, instead of forming the opening for carrying out the sample by cutting out a portion of the bottom plate 14, the opening is formed by removing a cut from the end plate 18 on the downstream side. You may. Further, it goes without saying that the arrangement pattern, hole diameter, inclination angle, etc. of the gas discharge holes 20 are not limited to those of the embodiment.

〔Effect of the invention〕

According to the sample transport device using air current according to the present invention, despite the simple structure, a sample plate such as a semiconductor wafer placed on a susceptor can be levitated without contact and transported while maintaining a contact-free state. It can be moved, and it can be picked up and transported without damaging the sample plate such as a wafer or contaminating the wafer. Also,
By forming a long guide path, the transport distance can be increased, and a sample plate such as a wafer placed still can be easily transported to a desired position.

Furthermore, unlike conventional mechanical chuck devices, there is no need to directly pink-amplify the sample plate such as a wafer, so there is no need for high positional accuracy at the pick-up section, and there is no need to change the wafer dimensions. .

Furthermore, it can be picked up even if it grows, and has a configuration that is highly versatile and easy to automate. Since it is long, has no mechanical movement mechanism, and has no wear parts, it not only has a long life and is easy to maintain, but also can be cheaper than a simple structure.

Furthermore, by improving the airtightness between the sample loading port and the sample mounting table such as the →J-Sepuku, contamination of other wafers, etc. can be minimized.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing a first embodiment of the present invention, FIG. 2 is a schematic cross-sectional view taken along the line ■-■ in FIG. 1, and FIG.
The figure is a cross-sectional view schematically showing the section taken along the line ■-■ in Figure 1.
FIG. 5 is a schematic sectional view for explaining the wafer pickup operation in the first embodiment, FIG. 5 is a schematic sectional view for explaining the wafer transport operation in the first embodiment,
The figure is a schematic cross-sectional view showing a second embodiment of the invention, FIG. 7 is a schematic cross-sectional view showing a third embodiment of the invention, and FIG. 8 is a schematic cross-sectional view showing a fourth embodiment of the invention. It is a schematic cross-sectional view.

Claims (1)

[Claims] Multiple gas discharge holes are drilled along the sample transport direction in the partition wall provided between the gas supply path into which high-pressure gas is introduced and the guide path for sample transport located at the bottom of this gas supply path. A sample inlet and a sample outlet are provided at upstream and downstream positions of the guide passage in the sample transport direction, respectively, and at least one of the plurality of gas discharge holes is located at the position of the sample inlet. It is formed as a pick-up discharge hole for guiding gas from the side surface of a stationary sample to the back surface of the sample to levitate the sample, and the other gas discharge holes are tilted at least in the sample transport direction to prevent airflow in the same direction. 1. A sample transport device using an air current, characterized in that it is formed as a transport discharge hole that forms a transport discharge hole.