CN213181298U - Wafer preloading device and automatic optical detector - Google Patents

Abstract

The application provides a wafer preloading device and automatic optical detector for send into the wafer and detect in the detection device of automatic optical detector according to presetting the state. The wafer preloading device comprises a rotating carrier for bearing and fixing a wafer to be preloaded, a transferring unit for placing the wafer into or removing the wafer from the rotating carrier, an identification unit for identifying the identity of the wafer, an adjusting unit for identifying the placement angle of the wafer and controlling the rotating carrier to transfer the wafer, and a cleaning unit for spraying inert gas to the first outer surface of the wafer borne on the rotating carrier to remove impurities. Wherein the rotary stage is further configured to rotate the wafer relative to the cleaning unit when the cleaning unit is in operation. The wafer preloading device utilizes the characteristic that the rotation angle is required to be regular before wafer detection, and the wafer preloading device cleans the rotation carrying platform when the rotation carrying platform bears the rotation carrying platform, so that a better cleaning effect can be obtained, and the modification cost is lower.

Description

Wafer preloading device and automatic optical detector

Technical Field

The utility model relates to a semiconductor manufacturing technology field, in particular to wafer preloading device to and contain this wafer preloading device's automatic optical detector.

Background

In the production process of semiconductor devices, a plurality of complicated processes, including etching, exposure, cleaning, etc., are required to be performed on a wafer, and an Automatic Optical Inspection (AOI) process is also included to determine the number of particles on the wafer surface. The accuracy of this process is directly related to the yield of the wafer flatness.

During the manufacturing and transporting processes of the wafer, some impurities may be adsorbed on the surface of the wafer. Although the portion of the impurities can be removed by the gas, if the portion of the impurities cannot be effectively removed, the portion of the impurities can be determined as particles on the surface of the wafer during the automatic optical inspection, thereby affecting the accuracy of the automatic optical inspection.

In the current production process, the wafer is mostly purged in a manual or mechanical mode before being subjected to automatic optical inspection. However, the manual purging can reduce the efficiency of wafer production, and the installation of a special machine purging device has the problems of low integration level and increased wafer manufacturing cost.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defects of the prior art, and provides a wafer preloading device with high integration level and convenient implementation, which specifically comprises the following technical scheme:

a wafer preloading device is used for sending a wafer into a detection device of an automatic optical detector for detection according to a preset state and comprises a rotary carrying platform used for carrying and fixing the wafer to be preloaded and a transfer unit used for putting the wafer into or removing the wafer from the rotary carrying platform, the wafer preloading device is also provided with an identification unit, an adjustment unit and a cleaning unit in the extending direction of the wafer preloaded by the rotating carrier relative to the rotating carrier, wherein the identification unit is used for identifying the identity of the wafer, the adjustment unit is used for identifying the placement angle of the wafer, and controls the rotary stage to rotate the wafer right based on the placement angle, the cleaning unit is configured to spray an inert gas to a first outer surface of the wafer carried on the rotary stage to remove impurities, the rotary carrying platform is also used for driving the wafer to rotate relative to the cleaning unit when the cleaning unit works.

The wafer preloading device provided by the application utilizes the characteristic that the wafer needs to pass through the matching of the adjusting unit and the rotating carrying platform before detection, and then the wafer is rotated by an angle so as to be regular, and the cleaning unit is correspondingly used for bearing the rotating carrying platform of the wafer, so that when the cleaning unit faces the first outer surface of the wafer and sprays inert gas to clean, the cleaning unit can synchronously drive the wafer to rotate through the rotating carrying platform, and the cleaning effect of the cleaning unit is improved. The wafer preloading device is low in modification cost and beneficial to cost control.

Preferably, the wafer preloading device further comprises a suction unit, and the suction unit is used for carrying the inert gas sprayed by the cleaning unit away from the wafer preloading device together with the cleaned impurities. The air suction unit can prevent the cleaned impurities from forming secondary pollution on the wafer.

Preferably, the suction unit is disposed in alignment with or higher than the first outer surface of the wafer, and the suction unit is disposed at least on one side of the rotary stage. The suction unit may be secured against or above the first outer surface to effectively absorb the inert gas ejected from the cleaning unit.

Preferably, the suction unit includes a first suction unit and a second suction unit that are arranged on opposite sides of the rotary stage. The first air suction unit and the second air suction unit are oppositely arranged to more completely absorb the inert gas.

Preferably, the cleaning unit includes at least one showerhead disposed toward the first outer surface for spraying an inert gas, and a gas line communicating with the showerhead. The shower nozzle can promote the impact pressure of inert gas, the gas circuit is used for providing the inert gas that the shower nozzle is clean needs.

Preferably, the gas pipeline and the rotary carrier are arranged at intervals, the number of the nozzles is multiple, and the nozzles are arranged at intervals along the extending direction of the gas pipeline. A plurality of the showerheads can act on more of the first outer surface of the wafer.

Preferably, the plurality of the showerhead is divided into at least two groups, wherein one group of the showerhead injects the inert gas from one side of the gas line toward the first outer surface, and the other group of the showerhead injects the inert gas from the other side of the gas line toward the first outer surface. The wafer pre-loading device has the advantages that the gas scouring effects at two different angles are formed on the wafer, and the cleaning efficiency of the wafer pre-loading device can be improved.

Preferably, the gas pipe is provided to be rotatable with respect to the rotation stage, and the cleaning unit is configured to eject the inert gas while oscillating back and forth with respect to the rotation stage. A larger relative movement range can be formed between the wafer and the spray head, and the phenomenon of uneven gas cleaning pressure on the wafer is further avoided.

Preferably, the cleaning unit further comprises a gas pressure regulating assembly for controlling the gas pressure of the inert gas ejected by the cleaning unit towards the first outer surface, and/or

The cleaning unit further comprises an air temperature adjustment assembly for controlling the air temperature of the inert gas ejected by the cleaning unit towards the first outer surface. By adjusting the pressure and temperature of the inert gas, the cleaning effect of the cleaning unit can be further improved.

The application also provides an automatic optical detector, which comprises a detection device for optically detecting the wafer and the wafer preloading device. Because the wafer preloading device is arranged, the surface of the wafer loaded on the detection device is cleaner, the impurities are less, and the automatic optical detector can be ensured to have higher detection accuracy.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic view of an internal frame of an automated optical inspection apparatus provided by the present invention;

fig. 2 is a schematic diagram of an internal frame of the wafer preloading device according to the present invention;

fig. 3 is a schematic structural diagram of a wafer preloading device according to the present invention;

fig. 4 is a schematic structural view of the wafer preloading device according to the present invention after a wafer is placed therein;

fig. 5 is a schematic view of a cleaning unit in the wafer preloading device according to the present invention;

fig. 6 is a schematic diagram of another embodiment of a cleaning unit in a wafer pre-loading device according to the present invention.

Description of reference numerals:

100-a wafer preloading device; 10-rotating the stage; 11-a rotation mechanism; 12-a chassis; 20-a transport unit; 30-an identification unit; 40-an adjustment unit; 50-a cleaning unit; 51-a spray head; 52-gas line; 60-a suction unit; 61-suction port; 62-a power source; 200-automatic optical detector; 201-detection means; 300-a wafer; 301-first outer surface.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without any creative effort belong to the protection scope of the present invention.

Furthermore, the following description of the various embodiments refers to the accompanying drawings, which are included to illustrate specific embodiments in which the invention may be practiced. Directional phrases used in this disclosure, such as "upper," "lower," "front," "rear," "left," "right," "inner," "outer," "side," and the like, refer only to the orientation of the attached drawing figures and, thus, are used in a better and clearer sense to describe and understand the present invention rather than to indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be considered limiting of the invention.

Referring to fig. 1, the present invention provides an automatic optical inspection apparatus 200, which includes an inspection apparatus 201 and the wafer pre-loading apparatus 100 according to the present invention. The wafer preloading device 100 is used for sending a wafer 300 (see fig. 4) into the inspection device 201 according to a predetermined state for automatic optical inspection. The predetermined states include the loading angle requirement of the wafer 300, the effective identification of the id of the wafer 300, and the surface cleanliness of the wafer 300. Typically, a plurality of wafers 300 are simultaneously stored in a housing mechanism (e.g., a wafer rack), and by picking up, loading and inspecting the plurality of wafers 300 one by one, an automatic optical inspection of all the wafers 300 stored in the housing mechanism can be achieved.

Please refer to fig. 2 and fig. 3 for a wafer preloading device 100 provided by the present application. The wafer preloading device 100 includes a rotation stage 10, a transfer unit 20, an identification unit 30, an adjustment unit 40, and a cleaning unit 50. Wherein the rotary stage 10 is rotatably disposed in the wafer preloading device 100. The transfer unit 20 is at least movable between the rotary stage 20 and the detection device 201, the transfer unit 20 has a clamping jaw (not shown) matching the wafer 300, and the transfer unit 20 transfers the wafer 300 from the rotary stage 10 to the detection device 201 for automatic optical inspection by the clamping jaw. The transfer unit 20 is also movable between the wafer rack and the rotary stage 10, and is used for picking up the wafer 300 on the wafer rack and placing it on the rotary stage 10 (see fig. 4).

The rotary stage 10 includes a rotary mechanism 11 and a base plate 12, and the rotary mechanism 11 can drive the base plate 12 to rotate in the wafer preloading device 100. The base plate 12 is used for carrying the wafer 300, and the base plate 12 fixes the wafer 300 by negative pressure or snap fit, and the wafer 300 can rotate synchronously with the base plate 12.

The wafer preloading device is further provided with an identification unit 30, an adjustment unit 40, and a cleaning unit 50 in the extending direction of the rotation stage 10 with respect to the wafer 300 preloaded thereon. The recognition unit 30 may be a camera or a bar code recognizer, and recognizes the identity information of the wafer 300 by recognizing the two-dimensional code or the bar code on the wafer 300, and the automatic optical inspection apparatus 200 can output the result corresponding to the identity of the wafer 300 after inspecting the wafer 300. The adjusting unit 40 is typically a camera, and can obtain the current placement angle of the wafer 300 after being placed on the rotary stage 10 by capturing an image of the wafer 300 and recognizing the image data. Because the wafer 300 is required to be placed at an angle in the automatic optical inspection, the adjustment unit 40 can identify the placing angle to control the rotary stage 10 to drive the wafer 300 to rotate so as to correct the posture of the wafer 300, so that the wafer 300 can be sent to the detection device 201 at a predetermined posture for automatic optical inspection.

When placed on the stage 10, the wafer 300 has a first outer surface 301 facing the recognition unit 30, the adjustment unit 40, and the cleaning unit 50. The recognition unit 30, the adjustment unit 40, and the cleaning unit 50 are disposed toward the first outer surface 301, so that the recognition unit 30 and the adjustment unit 40 can perform photographing or scanning recognition on the wafer 300. And the cleaning unit 50 is used for spraying an inert gas toward the first outer surface 301 of the wafer 300 to remove impurities adsorbed on the first outer surface 301. Since the wafer 300 is prone to adsorb impurities during the manufacturing and transportation processes, and the impurities may interfere with the results of the automatic optical inspection, the impurities may be peeled off from the first outer surface 301 by the cleaning unit 50, so as to improve the detection accuracy of the automatic optical inspection apparatus 200 of the present application.

Further, due to the rotatable nature of the rotary stage 10, when the cleaning unit 50 cleans the first outer surface 301, the rotary stage 10 can also drive the wafer 300 to rotate relative to the cleaning unit 50. Therefore, the inert gas sprayed by the cleaning unit 50 is in a changing state when acting on the area of the wafer 300, so that the defect of uneven brushing force on the first outer surface 301 caused by the pressure difference of the inert gas sprayed by the cleaning unit 50 can be eliminated, the cleaning effect of the wafer preloading device 100 is improved, and the detection efficiency of the automatic optical detector 200 is further improved.

According to the wafer preloading device 100, the adjusting unit 40 and the rotary carrier 10 are required to cooperate before wafer detection, and the rotary carrier 10 drives the wafer 300 to rotate to regulate the angle, the cleaning unit 50 is arranged corresponding to the rotatable rotary carrier 10, so that when the cleaning unit 50 sprays inert gas towards the first outer surface 301 of the wafer 300 for cleaning, the wafer 300 can be synchronously driven to rotate through the rotary carrier 10, and the cleaning effect of the cleaning unit 50 is improved. Theoretically, since the time consumption of the wafer 300 during the automatic optical inspection is usually 1-2min, when the wafer 300 is preloaded by the wafer preloading device 100 of the present application, it is only necessary to take time for preloading in the first wafer loading process, and the subsequent preloading process can automatically complete the preparation of the wafer 300 during the inspection of the previous wafer 300. Therefore, the wafer preloading device 100 of the present application can achieve higher inspection efficiency of the wafer 300 compared to the solution of manually cleaning the wafer 300. Because the cleaning operation is completed by the rotary carrier 10 with a regular posture, which is necessary for the wafer 300 before the automatic optical inspection, the wafer preloading device 100 of the present application can be implemented by simply improving the existing production line, and has the advantages of low modification cost and contribution to cost control.

It is to be noted that the inert gas sprayed by the cleaning unit 50 of the present application toward the first outer surface 301 may be nitrogen. Since the inert gas does not chemically react with the wafer 300, a sufficient gas scouring force can be provided and is relatively stable.

In one embodiment, the wafer preloading device 100 further includes a suction unit 60. The suction unit 60 includes a suction port 61 and a power source 62 connected to the suction port 61, and the inert gas ejected from the cleaning unit 50 and the cleaned impurities can be carried away from the wafer preloading device 100 by the negative pressure provided by the power source 62 through the suction port 61. It can be understood that, since the impurities on the wafer 300 may float in the air with the air flow after being stripped, and there is a risk of secondary contamination caused by the impurities falling back onto the wafer 300, the arrangement of the suction unit 60 can balance the pressure in the wafer preloading device 100 and simultaneously carry the impurities away from the wafer preloading device 100, thereby avoiding secondary contamination caused by the impurities.

In one embodiment, the suction unit 60 is further disposed in alignment with or above the first outer surface 301 of the wafer 300, and the suction unit 60 is disposed at least on one side of the rotary stage 10. The inert gas sprayed toward the wafer 300 by the cleaning unit 50 is mostly collected on the upper portion of the first outer surface 301 after being reflected by the first outer surface 301. The impurities carried away by the inert gas at this time are also accumulated on the upper portion of the first outer surface 301. Therefore, by disposing the suction unit 60, and particularly the suction port 61, flush with the first outer surface 301 or higher than the first outer surface 301, the effective coefficient of the suction unit 60 for impurities can be ensured and taken away from the wafer preloading device 100.

In one embodiment, the suction unit 60 further includes a first suction unit 601 and a second suction unit 602, and the first suction unit 601 and the second suction unit 602 are disposed at two opposite sides of the rotating stage 10 in parallel. The relative arrangement of the first suction unit 601 and the second suction unit 602 can improve the efficiency of the suction unit 60 in absorbing impurities, and avoid dead angles of impurities absorption that may be formed when only one suction unit 60 is used for blocking the wafer 300 or the rotary stage 10 or blocking the other components. The relative arrangement of the first suction unit 601 and the second suction unit 602 allows the wafer preloading device 100 of the present application to absorb the inert gas more completely.

In one embodiment, the cleaning unit 50 includes at least one showerhead 51, and a gas line 52 connected to the showerhead 51. The at least one showerhead 51 is disposed toward the first outer surface 301, and injects the inert gas delivered through the gas line 52 toward the first outer surface 301. The nozzle 51 has a limited action area on the first outer surface 301, and the wafer 300 is driven to rotate by rotating the carrier 10, so that the first outer surface 301 is completely cleaned.

In one embodiment, the gas line 52 is spaced apart from the rotation stage 10, and the gas line 52 extends along the first direction 001. The number of the showerhead 51 is plural, and the plural showerheads 51 are disposed on the gas pipe 52 at intervals along the first direction 001, i.e., the extending direction of the gas pipe 52. It will be appreciated that each showerhead 51 is also in communication with gas line 52. The plurality of nozzles 51 arranged at intervals can flush different areas of the first outer surface 301 of the wafer 300, and can also form overlapped flushing effects on partial areas of the wafer 300, thereby improving the cleaning efficiency. The first direction 001 may be any direction parallel to the rotation stage 10, and in some embodiments the first direction 001 may also extend obliquely to the rotation stage 10. When the projection of the gas line 52 on the rotation stage 10 is located on the rotation stage 10, the gas injection from the showerhead 51 to the first outer surface 301 can be ensured. Of course, in other embodiments, the projection of the gas pipeline 52 on the rotation stage 10 may also be spaced from the rotation stage 10, and in this case, the injection angle of the nozzle 51 needs to be adjusted to ensure that the gas injected by the nozzle 51 can act on the first outer surface 301.

Referring to fig. 5, the plurality of nozzles 51 are further divided into at least two groups, wherein the first group of nozzles 51 sprays the cleaning solution toward the wafer 300 from one side of the gas pipeline 52, and the second group of nozzles 51 sprays the cleaning solution toward the wafer 300 from the other side of the gas pipeline 52. Alternatively, the two sets of nozzles 51 may spray the cleaning solution toward the wafer 300 from two sides of the gas pipeline 52 at different angles, respectively, so as to form two different angle cleaning and flushing effects on the first outer surface 301 of the wafer 300, thereby improving the cleaning efficiency of the wafer cleaning and loading device 100 of the present application.

On the other hand, the two sets of nozzles 51 are arranged at intervals on the gas pipeline 52, and as shown in fig. 5, each of the nozzles 51 may be arranged at intervals in the length direction of the gas pipeline 52; or as shown in fig. 6, the showerheads 51 in each group are spaced apart from each other, and the showerheads 51 in different groups may be arranged on the same length of the gas pipe 52. Both the illustrations of fig. 5 and 6 can achieve similar cleaning effects for flushing the wafer 300 from two different angles.

It should be noted that in the schematic diagrams of fig. 5 and 6, the gas line 52 is viewed from a top view. The gas injection angle of the showerhead 51 at this time appears in two different directions of the horizontal direction. In actual operation, the nozzles 51 are set at an angle to inject the inert gas substantially vertically downward, and the two groups of nozzles 51 are represented by the different angles in fig. 5 and 6 only in the horizontal direction component thereof, and the horizontal direction angle does not affect the action of the nozzles 51 to inject the inert gas substantially vertically downward.

In one embodiment, the gas line 52 is also rotatably disposed relative to the rotating stage 10. I.e., the cleaning unit 50, is also rotatably disposed in the wafer preloading device 100. So that the cleaning unit 50 can perform reciprocating oscillation with respect to the rotary stage 10 while spraying the inert gas. The swinging motion of the gas pipe 52 can drive the plurality of nozzles 51 carried by the gas pipe to swing synchronously relative to the wafer 300, so that the inert gas ejected from the nozzles 51 is in a real-time angle changing state while the wafer 300 rotates along with the rotary stage 10. A larger relative movement range can be formed between the wafer 300 and the showerhead 51, thereby further avoiding the uneven flushing pressure of the inert gas on the wafer 300.

In one embodiment, the cleaning unit 50 further includes a gas pressure adjusting assembly (not shown) for controlling the gas pressure of the inert gas sprayed by the cleaning unit 50 toward the first outer surface 301. It can be understood that, due to the influence of different factors such as the size of the wafer 300, the ambient humidity, the amount of the ambient impurities, and the like, the pressure of the inert gas required for cleaning the first outer surface 301 is changed accordingly, and the pressure of the gas required by the cleaning unit 50 can be appropriately reduced under the ideal external conditions; in the case where the external conditions are relatively complicated, the pressure of the inert gas sprayed from the cleaning unit 50 may also be increased by the pressure adjusting assembly.

In one embodiment, the cleaning unit may further include an air temperature adjustment assembly (not shown) for controlling the air temperature of the inert gas sprayed by the cleaning unit 50 toward the first outer surface 301. Generally, the temperature of the inert gas can be maintained in the room temperature range, i.e., around 22 ℃. When the difference between the outside temperatures is too large, the air temperature adjusting assembly can control the temperature of the inert gas within the room temperature range in a heating/cooling mode, so as to avoid the adverse effect on the wafer 300, which may be caused by too high or too low temperature of the inert gas.

The automated optical inspection machine 200 includes an inspection apparatus 201 for optically inspecting a wafer 300, and the wafer pre-loading apparatus 100. Because the wafer preloading device 100 is provided, the surface of the wafer 300 loaded on the detection device 201 is cleaner and has less impurities, and meanwhile, the wafer 300 can be ensured to be in a regular state. Therefore, the automatic optical detector 200 has higher detection accuracy.

The above is an implementation manner of the embodiments of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principles of the embodiments of the present invention, and these improvements and decorations are also considered as the protection scope of the present invention.

Claims (10)

1. A wafer preloading device is used for sending a wafer into a detection device of an automatic optical detector for detection according to a preset state, and is characterized by comprising:

the wafer preloading device is further provided with an identification unit, an adjustment unit and a cleaning unit, wherein the identification unit is used for identifying the identity of the wafer, the adjustment unit is used for identifying the placement angle of the wafer and controlling the rotation carrier to rotate the wafer based on the placement angle, the cleaning unit is used for spraying inert gas to the first outer surface of the wafer borne on the rotation carrier to remove impurities, and the rotation carrier is further used for driving the wafer to rotate relative to the cleaning unit when the cleaning unit works.

2. The wafer preloading device of claim 1, further comprising a suction unit for carrying the inert gas ejected from the cleaning unit away from the wafer preloading device along with the purged foreign substances.

3. The wafer preload apparatus as claimed in claim 2, wherein said suction unit is disposed in alignment with or above said first outer surface of said wafer, and said suction unit is disposed at least on one side of said rotary stage.

4. The wafer preload apparatus as claimed in claim 3 wherein said suction unit comprises a first suction unit and a second suction unit arranged on opposite sides of said rotary stage.

5. The wafer preload apparatus as claimed in any one of claims 1 to 4, wherein said cleaning unit comprises at least one showerhead disposed toward said first outer surface for ejecting inert gas, and a gas line communicating with said showerhead.

6. The wafer preloading device of claim 5, wherein the gas lines are spaced from the rotary stage, and the plurality of showerheads are spaced along the extension direction of the gas lines.

7. The wafer preload apparatus as claimed in claim 6 wherein said plurality of said showerheads are divided into at least two groups, one of said groups of said showerheads ejecting inert gas from one side of said gas line toward said first outer surface and the other of said groups of said showerheads ejecting inert gas from the other side of said gas line toward said first outer surface.

8. The wafer preload apparatus as claimed in claim 6, wherein said gas line is rotatably disposed with respect to said rotary stage, and said cleaning unit is reciprocated with respect to said rotary stage while injecting the inert gas.

9. The wafer preload device as claimed in any one of claims 1 to 4, wherein said cleaning unit further comprises a gas pressure regulating assembly for controlling the gas pressure of the inert gas ejected by said cleaning unit towards said first outer surface, and/or

The cleaning unit further comprises an air temperature adjustment assembly for controlling the air temperature of the inert gas ejected by the cleaning unit towards the first outer surface.

10. An automated optical inspection machine comprising inspection apparatus for optically inspecting a wafer and a wafer preloading device as claimed in any one of claims 1 to 9.

Images