Wafer transfer robot

Abstract

A wafer transfer robot according to one embodiment of the present invention is a wafer transfer robot comprising a robot hand, a robot arm, and a driving unit, wherein a through hole is formed in the robot hand and a vision recognition mark is formed in the robot arm, and a vision unit is provided above the robot arm, and when the vision recognition mark of the robot arm is exposed through the through hole by aligning the vision recognition mark of the robot arm with the through hole of the robot hand, the vision unit confirms this and determines whether the robot arm has an accurate origin position setting.

Description

Technology Field

[0001] The present invention relates to a wafer transfer robot, and more specifically, to a wafer transfer robot in which, when a vision recognition mark displayed on a robot arm through a through-hole formed in a robot hand is precisely matched, a vision unit automatically recognizes the vision recognition mark exposed through the through-hole, thereby enabling constant monitoring of the accurate origin position setting and sagging of the robot arm, so as to maintain very precise and accurate wafer positioning and transfer precision, and furthermore, prevents minute sagging or vibration of the robot arm and hand even when used for a long time. Background Technology

[0002] Generally, semiconductor devices are manufactured by stacking multiple circuit patterns on a wafer through the selective and repetitive execution of processes such as photolithography, etching, ion implantation, diffusion, and metal deposition. To be manufactured into a semiconductor device, the wafer is not only transported to the semiconductor device manufacturing equipment where each unit process is performed, but also transferred within the equipment to specific locations for process execution or to configuration positions that assist in the process.

[0003] In such wafer transfer processes, each process is required to be limited to the wafer, which can be achieved by ensuring that the flat zone position of the wafer is accurately aligned with the location for process execution. Accordingly, general semiconductor device manufacturing equipment is equipped with a configuration for transferring wafers and a configuration for aligning wafers during the transfer process.

[0004] Recently, wafer transfer robots are required to process nanometer-scale fine patterns, so very precise and accurate wafer transfer performance and origin position setting are required. In addition, measures to prevent minute sagging and resulting vibration that may occur in the cantilevered robot arm over time are required. Prior art literature

[0005] Korean Patent Registration No. 0513401 (Registered on September 1, 2005) The problem to be solved

[0006] Accordingly, the present invention has been devised to resolve the above-mentioned problems. It aims to provide a wafer transfer robot that maintains very precise and accurate wafer positioning and transfer precision, and prevents minute sagging or vibration of the robot arm and hand even during long-term use, by enabling the accurate setting of the origin position and constant monitoring of sagging of the robot arm through the vision unit automatically recognizing the vision recognition mark exposed through the vision unit when the vision recognition mark displayed on the robot arm is accurately matched through the vision unit formed in the robot hand. means of solving the problem

[0007] According to one embodiment, the present invention for achieving the above objectives is characterized in that a wafer transfer robot comprising a robot hand, a robot arm, and a driving unit has a through hole formed in the robot hand and a vision recognition mark formed in the robot arm, a vision unit is provided above the robot arm, and when the vision recognition mark of the robot arm is exposed through the through hole by aligning the vision recognition mark of the robot hand with the through hole, the vision unit confirms this and determines whether the robot arm has an accurate origin position setting.

[0008] In addition, according to one embodiment, the through hole is formed in a circular shape, and the vision recognition mark is characterized by having a colored circular shape with a diameter larger than the diameter of the through hole, or a bar shape in which the circular shape is extended in one direction.

[0009] In addition, according to one embodiment, the robot arm is characterized in that one end of a first joint coupled to a robot hand and a second joint coupled to a driving unit are rotatably linked, a protruding extension is formed on the upper plate of the second joint, and a bar-shaped vision recognition mark is formed on the extension, and the through hole and the vision recognition mark are precisely aligned on a plane when the first joint and the second joint are in a completely folded origin position.

[0010] In addition, according to one embodiment, the link of the first joint comprises: a link body having a timing belt and a timing pulley for driving a robot arm inside; an end effector clamp rotatably coupled to the upper part of the link body with a robot hand coupled to one side; and a pulley support coupled to the lower part of the link body; wherein a first bearing is provided between the link body and the end effector clamp to support the lower part of the end effector clamp, and a second bearing is further provided between the link body and the pulley support to support the lower part of the timing pulley.

[0011] In addition, according to one embodiment, the first bearing is a cross roller bearing to respond to thrust loads and radial loads, and the second bearing is a ball bearing to respond to radial loads.

[0012] In addition, according to one embodiment, the driving unit comprises: a cylindrical housing; R, T, and Z axis driving motors provided inside the cylindrical housing; and a seal provided between the R, T, and Z axis driving motors and a robot arm.

[0013] In addition, according to one embodiment, the seal portion comprises a magnetic fluid seal (Ferroseal) provided at the top of the R, T, and Z axis drive motors; and a metal bellows provided around the magnetic fluid seal. Effects of the invention

[0014] The present invention, as described above, has the effect of maintaining very precise and accurate wafer position and transfer precision because, when a vision recognition mark displayed on a robot arm through a through hole formed in a robot hand is exactly matched, the vision unit automatically recognizes the vision recognition mark exposed through the through hole, thereby enabling constant monitoring of the accurate origin position setting and position change of the robot arm.

[0015] In addition, by adding a support bearing to the lower part of the robot arm to prevent sagging during operation, it is possible to prevent minute sagging or vibration that may occur in the cantilever-shaped robot arm and hand due to prolonged use. Brief explanation of the drawing

[0016] FIG. 1 is an overall perspective view of the wafer transfer robot of the present invention. FIG. 2 is a drawing showing the internal configuration of the drive unit of FIG. 1. FIG. 3 is a drawing showing (a) a withdrawn state and (b) a home position state of a robot arm according to the present invention. FIG. 4 is a cross-sectional view showing the internal configuration of a link of a robot arm according to the present invention. Specific details for implementing the invention

[0017] The terms used herein are used merely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising,” “having,” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described herein, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0018] Unless otherwise defined in this specification, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains.

[0019] Terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this specification.

[0020] Hereinafter, the configuration and operational relationship of a wafer transfer robot for a vacuum chamber according to one embodiment of the present invention will be examined in detail with reference to the attached drawings.

[0021] FIG. 1 is a perspective view showing the wafer transfer robot of the present invention in its entirety, FIG. 2 is a drawing showing the internal configuration of the drive unit of FIG. 1, FIG. 3 is a drawing showing (a) the pulled-out state and (b) the origin position state of the robot arm according to the present invention, and FIG. 4 is a cross-sectional view showing the internal configuration of the link of the robot arm according to the present invention.

[0022] Referring to FIGS. 1 to 4 above, the wafer transfer robot (1000) of the present invention is largely composed of a robot hand (1100), a robot arm (1200), and a driving unit (1300) according to one embodiment.

[0023] First, the robot hand (1100) is a component for placing and transporting the wafer (W) in a certain position, such as inside a vacuum chamber, with the wafer placed thereon. The robot hand (1100) has a through hole (H) formed therein to recognize the origin position of the robot arm (1200) by a vision unit (not shown) described later. At this time, the through hole (H) may be a circular hole as shown in the drawing.

[0024] Additionally, the robot hand (1100) is mounted on one end of the robot arm (1200), and a vision recognition mark (M) is formed on the robot arm (1200) in correspondence with the through hole (H). Accordingly, when the robot arm (1200) is driven, the vision recognition mark (M) exposed through the aforementioned through hole (H) can be recognized by being constantly captured by a vision unit (not shown) provided above the robot arm (1200).

[0025] At this time, the vision recognition mark (M) may be a colored circle having a diameter larger than the diameter of the through hole (H), or a bar shape in which the circle is extended in one direction.

[0026] That is, when the vision recognition mark (M) of the robot arm (1200) aligns with the through hole (H) of the robot hand (1100), the vision recognition mark (M) is exposed through the through hole (H). For example, if the through hole (H) is displayed entirely black, the vision unit (not shown) determines through image analysis that the robot arm (1200) is set to the correct origin position. If the image of the through hole (H) confirmed by the vision unit (not shown) is not displayed entirely black, it can be expected that an error, such as a slight sagging, has occurred in the cantilever-shaped robot arm (1200), and as a result, it can be determined that the origin position setting of the robot arm (1200) initially set has been misaligned.

[0027] For example, a vision unit (not shown) can determine whether the home position setting is normal or abnormal through vision AI (artificial intelligence) image analysis, etc. In this case, if it is determined that the home position setting is abnormal, an alarm can be displayed to the administrator via wired or wireless communication, and the administrator can correct the misaligned home position of the robot arm (1200) to the initial accurate setting position at any time through maintenance.

[0028] Additionally, the robot arm (1200) is rotatably linked to one end of a first joint (1210) coupled to a robot hand (1100) and a second joint (1220) coupled to a driving unit (1300). Here, the configuration of the first joint (1210) and the second joint (1220) exemplified is a configuration according to one embodiment for the purpose of explanation, and the present invention specifies that it can be configured with three or more joints according to other embodiments.

[0029] Additionally, according to one embodiment, a protruding extension (1221) is formed on the upper plate of the second joint (1220), and a bar-shaped vision recognition mark (M) is formed on the extension (1221). Accordingly, referring to FIG. 3, when the first joint (1210) and the second joint (1220) are in a completely folded origin position, the through hole (H) and the vision recognition mark (M) are precisely aligned on a plane, thereby exposing a colored (e.g., black) dot (M) through the through hole (H).

[0030] Accordingly, through the above-described configuration, the user can easily set the origin position of the transfer robot (1000) by applying the through hole (H) and the vision recognition mark (M) together to the transfer robot (1000) of the present invention, thereby increasing user convenience. In addition, the origin position of the robot arm (1200) that has been set can be checked automatically and at all times through the through hole (H) and the vision recognition mark (M) at the origin position of the robot arm (1200), and the positional accuracy status of the transfer robot (1000) can be continuously checked through constant position verification and monitoring even while the robot arm (1200) is in operation.

[0031] Additionally, referring to FIG. 4, according to one embodiment, the link of the first joint (1210) comprises: a link body (1211) having a timing belt (1212) and a timing pulley (1213) for driving a robot arm (1200) inside; an end effector clamp (1110) rotatably coupled to the upper part of the link body (1211) with a robot hand (1100) coupled to one side; and a pulley support (1214) coupled to the lower part of the link body (1211).

[0032] Additionally, a first bearing (1215) is provided between the link body (1211) and the end effector clamp (1110) to support the lower part of the end effector clamp (1110) without sagging, and a second bearing (1216) is provided between the link body (1211) and the pulley support (1214) to support the lower part of the timing pulley (1212).

[0033] In addition, according to one embodiment, a cross roller bearing may be applied to the first bearing (1215) to simultaneously respond to thrust loads (axial loads) and radial loads (lateral loads perpendicular to the axial direction). The cross roller bearing is a bearing with a compact structure in which rollers are arranged in a straight line between the inner ring and the outer ring. Since the rollers are arranged in a straight line, it can withstand complex loads in all directions simultaneously as a single unit, thus having the advantage of being able to be assembled regardless of the direction of the load.

[0034] In addition, according to one embodiment, a ball bearing may be applied to the second bearing (1216) to respond to a radial load.

[0035] Additionally, referring to FIG. 4, an axial protrusion (1214a) is formed on the upper part of the pulley support (1214), and the inner ring of the ball bearing (1216) can be fitted and fixed around the protrusion (1214a).

[0036] Specifically, in the past, since there was no second bearing (1216) supporting the pulley support (1214) inside the robot arm (1200), as time passed in this state, slight misalignment occurred in the internal parts of the robot arm (1200) due to sagging or vibration caused by the load, and many adverse effects occurred, such as the home position setting of the robot arm (1200) being misaligned due to the slight misalignment phenomenon, or the transfer precision of the wafer (W) being reduced as a result.

[0037] Accordingly, the present invention allows a vision unit (not shown) to constantly monitor the origin position setting through image analysis, thereby automatically determining whether the origin position setting is normal and the degree of misalignment. Additionally, it can display and transmit an alarm regarding an abnormal origin position or a request for resetting to an administrator, thereby maintaining a precise and accurate origin position setting of the robot arm (1200) and high wafer (W) transfer precision.

[0038] Additionally, referring to FIG. 2, the driving unit (1300) comprises: a cylindrical housing (1310); R, T, and Z axis driving motors (1330) (1340) (1350) provided inside the cylindrical housing (1310); and a seal (Seal, 1320) provided at the top of the R, T, and Z axis driving motors.

[0039] The robot arm (1200) can be driven stably even in a high vacuum state by the seal portion (1320). According to one embodiment, the seal portion (1320) may be composed of a coaxial magnetic fluid seal (Ferroseal, 1321) for perfect sealing; and a metal bellows (1322) provided around the magnetic fluid seal.

[0040] According to one embodiment, the R and T axis drive motors (1330) (1340) may be direct drive motors to have high positional precision.

[0041] In particular, in a robot arm (1200) structure having a thin link, it is more important to prevent a decrease in precision due to deformation of the robot arm (1200) when the robot arm is driven. To this end, as described above, a cross roller bearing as a first bearing (1215) and a ball bearing as a second bearing (1216) can be applied to the upper and lower parts of the pivot axis of the link body (1211).

[0043] As described above, the present invention allows for the accurate setting of the origin position and constant monitoring of the sagging of the robot arm (1200) by automatically recognizing and analyzing the vision recognition mark (M) exposed through the vision recognition mark (M) when the vision recognition mark (M) displayed on the robot arm (1200) is accurately matched through the vision recognition mark (M) formed in the robot hand (1100), thereby maintaining very precise and accurate positional accuracy and transfer accuracy of the wafer (W) to respond to nanometer-scale semiconductor processing.

[0044] In addition, by adding a support bearing (1215) (1216) to the lower part of the robot arm (1200) to prevent sagging during operation of the robot arm, the occurrence of minute sagging or vibration that may occur in the cantilever-shaped robot arm (1200) and robot hand (1100) due to long-term use is prevented.

[0046] Furthermore, the present invention is not limited solely to the embodiment described above. Since the same effect can be achieved even when the detailed configuration, number, or arrangement structure of the device is changed, it is hereby specified that those skilled in the art can add, delete, or modify various configurations within the scope of the technical concept of the present invention. Explanation of the symbols

[0047] 1000 : Wafer transfer robot (of the present invention) 1100 : Robot Hand 1200 : Robotic Arm 1210, 1220: 1st joint, 2nd joint 1110: End Effector Clamp 1211 : Link body 1212, 1213: Timing belt, timing pulley 1214 : Pulley support 1221 : Extension 1300 : Drive unit 1310 : Housing 1320 : Seal part 1321, 1322: Ferroseal, metal bellows 1330, 1340, 1350: R, T, Z-axis drive motors H : Through hole M: Vision recognition mark W : Wafer

Claims

Claim 1 In a wafer transfer robot comprising a robot hand, a robot arm, and a drive unit, a through hole is formed in the robot hand and a vision recognition mark is formed on the robot arm, and a vision unit is provided above the robot arm; when the vision recognition mark of the robot arm is exposed through the through hole by aligning the vision recognition mark of the robot arm with the through hole of the robot hand, the vision unit confirms this and determines whether the robot arm has an accurate home position setting; the through hole is formed in a circular shape, and the vision recognition mark has a colored circle having a diameter larger than the diameter of the through hole, or a bar shape in which the circle is extended in one direction; the robot arm has a first joint coupled to the robot hand and one end of a second joint coupled to the drive unit rotatably linked together, and a protruding extension is formed on the upper plate of the second joint and a bar-shaped vision recognition mark is formed on the extension; when the first joint and the second joint are in a completely folded home position, the through hole and the vision recognition mark are precisely aligned on a plane, and the robot hand When the vision recognition mark of the robot arm exactly aligns with the through hole, the vision recognition mark is exposed through the through hole; however, if the through hole is displayed entirely black, the vision unit determines through image analysis that the robot arm is set to an accurate origin position and is in a normal state; and if the image of the through hole confirmed by the vision unit is not displayed entirely black, it determines that an error including minute sagging has occurred in the robot arm and that the initially set origin position of the robot arm is misaligned and is in an abnormal state, and then displays an alarm to the administrator via wired or wireless communication, and the link of the first joint comprises: a link body equipped with a timing belt and a timing pulley for driving the robot arm inside; an end effector clamp rotatably coupled to the upper part of the link body with a robot hand coupled to one side; and a pulley support coupled to the lower part of the link body;A wafer transfer robot comprising: a link body and an end effector clamp; a first bearing is provided between the link body and the end effector clamp to support the lower portion of the end effector clamp; a second bearing is provided between the link body and the pulley support to support the lower portion of the timing pulley; the first bearing is a cross roller bearing to respond to thrust loads and radial loads, and the second bearing is a ball bearing to respond to radial loads; and the drive unit comprises: a cylindrical housing; R, T, and Z-axis drive motors provided inside the cylindrical housing; and a seal unit provided between the R, T, and Z-axis drive motors and a robot arm; wherein the seal unit comprises: a ferroelectric seal provided at the top of the R, T, and Z-axis drive motors; and a metal bellows provided around the ferroelectric seal. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 delete

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