JP2004165331A - Local cleaning transfer chamber and local cleaning treatment equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a local cleaning transfer chamber and local cleaning treatment equipment that can easily adjust atmospheric pressure inside a transfer room and maintain a clean environment without sharply increasing the amount of blast. <P>SOLUTION: The local cleaning transfer chamber comprises a number of openings that are provided on the floor surface of a wafer transfer chamber while a hand ring unit is sandwiched and discharge air from a fan filter unit, and an opening ratio adjustment mechanism that covers at least one portion of the openings and adjusts the opening ratio. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a locally-cleaned transfer chamber and a locally-cleaned processing apparatus. More specifically, in a locally-cleaned semiconductor processing apparatus, the pressure in the transfer chamber can be easily adjusted and the clean environment can be reduced without greatly increasing the amount of air blown. The present invention relates to a locally cleaned wafer transfer chamber that can be held.
[0002]
[Prior art]
The quality of a wafer used as a material for a semiconductor IC deteriorates when foreign matter adheres to the surface thereof, and is inspected by an optical foreign matter inspection device. The inspection is performed by a series of operations, and the wafer stored in the wafer cassette is conveyed to, for example, an inspection stage, air-adsorbed to the chuck unit, and rotated.
Therefore, conventionally, a rotation mechanism such as a motor is provided on a wafer pre-alignment stage or inspection stage. The rotation mechanism is used to rotate the wafer to perform angular positioning (θ positioning). In particular, in the case of V-notch positioning, angular positioning and center positioning are performed by a side chuck method in which three points are in contact with the outer periphery of the wafer. (For example, refer to Patent Document 1). However, since the wafer is rotated using a rotating mechanism such as a motor, there is a problem of dusting of metal particles due to sliding of a rotating part.
[0003]
On the other hand, when the wiring pattern formed on the wafer is miniaturized and the process becomes 0.25 μm or more, and the diameter of the wafer becomes a large diameter of about 300 mm, the influence of the foreign matter increases accordingly. To that extent, the yield of the wafer itself and of the chips formed on the wafer is also reduced. Therefore, it is not enough to clean only the room where the conventional semiconductor manufacturing apparatus is installed. No matter how much the cleanliness in the room is increased, there is a limit, so the semiconductor wafer is processed by a local cleaning system, a so-called mini-en system.
The local cleaning device is usually a device with a high degree of sealing, and keeps the inside at a positive pressure to prevent foreign matter from entering from the outside. The degree of cleanliness is reduced to about class 0.01. The internal positive pressure is generated by sending clean air into the inside of the air from a fan through a filter.
The loading and unloading of a workpiece to be processed, such as a wafer, into and out of the apparatus is usually carried out in a sealed pod.The pod is independently closed and tightly mounted on the apparatus, and the lid is closed. An opening mechanism FOUP (FRONT OPENING UNIFIED PAD) is provided (for example, see FIGS. 1 and 8 of Patent Document 2). Further, a wafer transfer device for transferring the wafer, pre-aligning the wafer on the pre-alignment stage, and transferring the wafer to the inspection stage is built therein.
Foreign matter due to dust generated in the wafer transfer device and the pre-alignment stage is discharged from the lower side of the apparatus by clean downflow air discharged from an air cleaning fan filter unit (FFU) provided on the ceiling of the apparatus. (See, for example, FIGS. 3 and 7 of Patent Document 3).
[0004]
[Patent Document 1]
JP-A-4-320043 [Patent Document 2]
JP 2000-173911 A [Patent Document 3]
JP 2000-188320 A
[Problems to be solved by the invention]
The amount of clean downflow air blown out from the air cleaning FFU is controlled so that the pressure in the wafer transfer chamber becomes a constant positive pressure in order to maintain a clean environment.
The locally-cleaned wafer transfer chamber is periodically cleaned, but when the use period is prolonged, the exhaust pressure increases, and the amount of air discharged from the FFU increases in order to keep the pressure in the wafer transfer chamber constant. .
When the amount of air discharged from the FFU is large, clogging of the filter is apt to occur, and dust contained in the filtered air is not sufficiently removed, which causes a reduction in cleanliness. Further, when the amount of air discharged from the FFU increases, the air flow collides with a transport device or the like, disrupting the flow of air, causing foreign matter to stay and flutter. That causes contamination of the wafer.
The object of the present invention has been made in view of the above, and has a local cleaning transfer chamber capable of maintaining a clean environment without easily increasing the air flow rate by easily adjusting the air pressure in the transfer chamber, and An object of the present invention is to provide a local cleaning apparatus.
[0006]
[Means for Solving the Problems]
The feature of the local cleaning transfer chamber and the local cleaning processing apparatus of the present invention for achieving such an object is that air from the fan filter unit is provided on the floor of the local cleaning transfer chamber with the handling unit interposed therebetween. It has a number of openings to be discharged, and an opening ratio adjustment mechanism that covers at least a part of these openings and adjusts the opening ratio.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
As described above, in the present invention, a large number of openings for discharging air from the FFU are provided on the floor in the transfer chamber with the handling unit interposed therebetween, and the opening ratio of these openings is adjusted. When the amount of air blow increases greatly, the internal pressure of the transfer chamber can be adjusted by increasing the aperture ratio without increasing the amount of air blow.
As a result, it is possible to easily realize a locally-cleaned transfer chamber and a locally-cleaned processing apparatus capable of easily adjusting the air pressure in the transfer chamber and maintaining a clean environment without greatly increasing the air blowing amount.
[0008]
【Example】
FIG. 1 is a schematic view for explaining an internal state of a wafer inspection apparatus having a local cleaning transfer chamber according to the present invention, FIG. 2 is a longitudinal sectional view of FIG. 1, and FIG. It is an external view.
In FIG. 3, reference numeral 20 denotes a wafer inspection apparatus of a mini-en system, and reference numeral 10 denotes a locally cleaned wafer transfer chamber. A fan filter unit (FFU) 11 for sending air into the room is provided above the locally cleaned wafer transfer chamber 10, and a filter for purifying air is provided on the front side on the air blowing side. 12a and 12b are pods storing 13 or 25 wafers, and are mounted on FOUP openers 13a and 13b.
The pods 12a and 12b have a security cover at an opening on the front side of the apparatus. The lid is opened by each opener when the pods 12a and 12b are mounted on the FOUP openers 13a and 13b.
[0009]
The FOUP opener 13a on the right side of the apparatus on which the pod 12a is mounted in FIG. 3 is located at a wafer load position (load port), and corresponds to the pre-alignment stage inside the apparatus. The FOUP opener 13b on the left side on which the pod 12b is placed is at a wafer unload position (unload port).
In FIG. 1, which shows the inside of the locally cleaned wafer transfer chamber 10, reference numeral 14 denotes a wafer handling unit, which takes out the inspected wafer from the inspection stage 16 and transfers it to the pod 12b. Then, the next inspection wafer is taken out from the pod 12a, sent to the pre-alignment stage 15, and transferred to the inspection stage 16 after the pre-alignment. Reference numeral 14a denotes a unit moving mechanism (a guide rail portion) of the wafer handling unit.
The pre-alignment stage 15 is a stage that places a wafer on a table and performs center positioning (centering) and positioning in the direction of a V notch or orientation flat (OF) (θ positioning). It has an XY stage 15a having an XY moving mechanism, and a rotating θ stage 15b.
[0010]
Openings for discharging air from the FFU 11 (see FIG. 2) are formed in the floor plate 1 of the locally cleaned wafer transfer chamber 10 as rectangular openings 2, 2 at predetermined intervals with the guide rail 14a of the wafer handling unit 14 interposed therebetween. Are equally arranged and provided in two rows before and after. The moving covers 3 and 3 that cover a part of the openings 2 are provided on the floor plate 1 corresponding to the openings 2 so as to cover the openings 2 in two rows.
FIG. 2 is a longitudinal sectional view of the locally cleaned wafer transfer chamber 10. A wafer handling unit 14 is provided at the center. The FFU 11 provided on the ceiling side includes a fan 11a and a filter 11b.
A controller 17 for controlling the wafer handling unit 14 and the pre-alignment stage 15 of the locally cleaned wafer transfer chamber 10 is provided below the pre-alignment stage 15. Further, the floor surface of the locally cleaned wafer transfer chamber 10 has a double structure as shown in FIG. The floor plate 1 is a floor surface located above the bottom plate 5 a on the bottom surface of the housing 5. Openings 2 are provided at predetermined intervals in a floor plate 1 above this, and a moving cover 3 is installed on the opening 2.
As a result, the air 6 from the FFU 11 passes through the opening 2, passes through the space between the upper floor plate 1 and the bottom plate 5a, and is discharged to the outside via the exhaust holes 7 and the like.
[0011]
As shown in the enlarged view of the relationship between the floor plate 1 and the movable cover 3 shown in the lower side of FIG. 2 and the plan view of FIG. 1, the movable cover 3 is arranged to slide on the floor plate 1 so that the opening is opened. 2 can be adjusted. In other words, an adjusting mechanism for adjusting the opening ratio of the opening 2 by the moving cover 3 is formed. Therefore, at both ends of the moving cover 3, long holes 3 a (see FIG. 1) are provided, and fixing screws 4 that pass through the long holes 3 a and fix the moving cover 3 are attached to the floor plate 1. Screwed at both ends.
Therefore, the opening ratio of the opening 2 can be adjusted by loosening the fixing screws 4 on both sides and manually sliding the moving cover 3. The initial opening ratio is suppressed to about 40% and is kept low. When the control is such that the air blowing amount is largely increased, the opening ratio is increased from 50% to more. As a result, the control of the air blowing amount is returned, and it is not necessary to greatly increase the air blowing amount. Whether or not the control is such that the air blowing amount is greatly increased is detected by, for example, the current or voltage of the fan of the FFU 11.
The air volume of the FFU 11 may be directly measured by an air volume meter, and a scale indicating an aperture ratio is provided around the long hole 3a in order to confirm the adjustment position of the moving cover 3.
As a result, the amount of air flowing down the FFU 11 that sends air into the device can be adjusted by adjusting the aperture ratio of the opening 2.
[0012]
In addition, since the moving cover 3 is provided along the floor plate 1, the moving cover may be automatically moved by a moving mechanism in accordance with the current air flow amount so as not to increase the air flow amount. In this case, the moving cover 3 and a moving mechanism for the moving cover 3 may be arranged on the back side of the floor panel 1. As a result, the problem of dust flowing into the transfer chamber by the moving mechanism does not occur.
Further, in this embodiment, since the controller 17 of the wafer handling unit 14 is provided below the pre-alignment stage 15, the locally-cleaned wafer transfer chamber 10 has a small number of irregularities inside the Are provided with the guide rail 14a of the wafer handling unit 14 interposed therebetween, so that the downflow air flow is less likely to be disturbed. Therefore, the structure is such that dust hardly rises to the upper part.
[0013]
As described above, in the embodiment, the example in which the opening on the floor surface is rectangular has been described, but the opening is not limited to the rectangle.
Further, in the embodiment shown in FIG. 1, the wafer cleaning chamber for local cleaning according to the present invention is used for a wafer inspection apparatus. Of course, the present invention can be applied to a wafer processing apparatus in general. Further, the present invention is not limited to such a wafer processing apparatus, and can be applied to a processing apparatus that transports various works including a liquid crystal substrate.
[0014]
【The invention's effect】
As described above, in the present invention, a large number of openings for discharging air from the FFU are provided on the floor in the transfer chamber with the handling unit interposed therebetween, and the opening ratio of these openings is adjusted. When the amount of air blow increases greatly, the internal pressure of the transfer chamber can be adjusted by increasing the aperture ratio without increasing the amount of air blow.
As a result, it is possible to easily realize the local clean transfer chamber and the local clean processing apparatus that can easily adjust the air pressure in the transfer chamber and maintain the clean environment without greatly increasing the air blowing amount.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating an internal state of a wafer inspection apparatus having a local cleaning transfer chamber according to the present invention.
FIG. 2 is a longitudinal sectional view of FIG.
FIG. 3 is an external view of a wafer inspection apparatus of a mini-en system.
[Explanation of symbols]
1 ... floor board, 2 ... opening,
3 ... moving cover, 3a ... long hole, 4 ... fixing screw,
5 ... housing, 5a ... bottom plate, 6 ... air flow,
7: exhaust hole, 10: locally cleaned wafer transfer chamber,
11 ... Fan filter unit (FFU),
12a, 12b ... pod,
13a, 13b ... FOUP opener,
14: wafer handling unit, 15: pre-alignment stage,
16: inspection stage, 17: controller, 20: mini-en system wafer inspection device.

Claims (5)

In the local clean transfer room that has a handling unit and blows clean air into the room by the fan filter unit to perform local clean,
A large number of openings provided on the floor of the clean transfer chamber with the handling unit interposed therebetween for discharging air from the fan filter unit, and openings for covering at least a part of these openings and adjusting the opening ratio thereof; A local clean transfer chamber equipped with a rate adjustment mechanism. Further, the locally-cleaned transfer chamber is a locally-cleaned wafer transfer chamber, the handling unit is the wafer handling unit, and a pre-alignment stage is provided adjacent to the wafer handling unit; Are arranged at predetermined intervals, the aperture ratio adjustment mechanism has a cover that covers the opening, and the cover is slid and adjusted. 2. The locally-cleaned wafer transfer chamber according to claim 1, wherein the wafer transfer chamber is provided on the side. In the local cleaning processing device having a handling unit and having a local cleaning transfer chamber that blows clean air into the room by the fan filter unit and performs local cleaning,
A large number of openings provided on the floor of the clean transfer chamber with the handling unit interposed therebetween for discharging air from the fan filter unit, and openings for covering at least a part of these openings and adjusting the opening ratio thereof; A local cleaning processing device including a rate adjusting mechanism. In a locally-cleaned wafer processing apparatus having a wafer handling unit and having a locally-cleaned wafer transfer chamber that blows clean air into a room by a fan filter unit to locally clean,
Numerous openings provided on the floor of the wafer transfer chamber with the wafer handling unit interposed therebetween for discharging air from the fan filter unit, and an opening ratio for covering at least a part of these openings and adjusting the opening ratio A locally cleaned wafer processing apparatus including an adjustment mechanism. Further, a pre-alignment stage is provided adjacent to the wafer handling unit, the plurality of openings are arranged at predetermined intervals, and the opening ratio adjustment mechanism has a cover covering the openings. 5. The local cleaning wafer processing apparatus according to claim 4, wherein a slide adjustment is performed, and a controller of the wafer handling unit is provided below the pre-alignment stage.

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