Robotic end effector for wafer transport system

Abstract

Embodiments of the present disclosure provide a robot end effector for a wafer transfer system, suitable for high temperature environment, the robot end effector comprising an arm adapter unit and a finger unit, wherein the arm adapter unit is connected between an arm of the robot and the finger unit; and the finger unit is integrally formed from a ceramic material and comprises a palm portion and fingers, wherein the palm portion is connected to the arm adapter unit, an adsorptive quartz pad is fixed on the palm portion, the fingers extend outwardly from the palm portion, and a quartz support pad is arranged at an end of the fingers away from the palm portion. A robot for a wafer transfer system is also provided.

Description

Technical Field

[0001] The embodiments disclosed herein belong to the field of robotics, and more specifically, relate to a robotic end effector for a wafer transfer system. Background Technology

[0002] In the wafer front-end process, rapid thermal processing of wafers is required in high-temperature chambers to eliminate lattice defects. The temperatures in these chambers can reach 420°C. Directly placing or removing wafers into or from these chambers by operators could result in injury. Furthermore, to improve the efficiency of the high-temperature chambers, it is desirable to place or remove wafers as quickly as possible. In such cases, robotic arms are typically used to place or remove wafers from the high-temperature chambers, preventing operator injury and improving processing and chamber utilization. Currently, gripping robotic arms and suction robotic arms are commonly available on the market.

[0003] Figure 1 This illustrates a gripping robotic hand known to the inventor. For example... Figure 1 As shown, the gripping robot includes a gripping base 11 and a finger 12. The finger 12 is made of ceramic, and one side of the finger is fixed to the back of the gripping base 11 by a screw. A gripping stop 13, fixed by a stainless steel screw 14, is provided at the fingertip of the finger 12 away from the gripping base 11. When gripping a wafer, a push rod 15 located in the inner cavity of the gripping base extends forward, pushing the wafer forward until it abuts against the gripping stop 13. At this point, the push rod 15 and the gripping stop 13 together grip the wafer, and the wafer is transported along with the movement of the robot.

[0004] exist Figure 1 In the gripper shown, the ceramic used to make the fingers is primarily composed of alumina, which has a very low coefficient of thermal expansion. Screws, on the other hand, are typically made of stainless steel, which has a higher coefficient of thermal expansion than alumina. Furthermore, stainless steel is stronger than alumina. During operation, the gripper frequently enters and exits a high-temperature chamber. The stainless steel screws expand due to heat, while the fingers hardly expand. Thus, the expanded screws can cause the fingers to crack.

[0005] Figure 2 shows a known adsorption-type robotic arm. The robotic arm 22 is fixed to the clamping base 21 by screws. The front end of the robotic arm 22 is provided with at least two adsorption devices 23 for adsorbing the wafer 24. In this way, the robotic arm 22 can be used to place the wafer 24 into the high-temperature chamber or remove the wafer 24 from the high-temperature chamber.

[0006] The main component of a regular wafer is silicon. It is round in shape, with a diameter of 300 mm and a thickness of 0.7 mm. At room temperature, the surface of the wafer is very flat. When picking up and placing a wafer, the force applied by the fingers to the wafer includes an upward supporting force, an adsorption force applied through multiple adsorption holes, and a frictional force in the horizontal direction.

[0007] After being heated in a high-temperature chamber, the wafer softens, warps, and becomes uneven. When the wafer is removed from the high-temperature chamber, it is no longer heated and gradually cools and hardens. During the hardening process, the suction holes restrict the wafer's deformation. At this point, multiple forces of different directions and magnitudes act on the wafer, causing it to crack. Summary of the Invention

[0008] In view of the above problems, at least one embodiment of this disclosure provides a robotic end effector suitable for high-temperature environments, including an arm adapter unit and a finger unit, wherein,

[0009] The arm adapter unit connects the robot's arm and the finger unit; and

[0010] The finger unit is integrally formed from ceramic material and includes a palm part and fingers. The palm part is connected to the arm adapter unit. An adsorption quartz pad is fixed on the palm part. The fingers extend outward from the palm part, and a quartz support pad is provided at the end of the fingers away from the palm part.

[0011] The adsorption-type quartz pad has an adsorption surface and a wafer contact surface. The adsorption surface is provided with air holes connected to a vacuum device. The height of the quartz support pad relative to the finger is equal to the height of the wafer contact surface relative to the palm portion.

[0012] The robot end effector includes a spring clip, which includes a base and a spring wire. The spring wire includes a first wire portion and a second wire portion. The first wire portion extends along the extension direction of the base, and the second wire portion is connected to the first wire portion and forms an angle with the first wire portion.

[0013] The adsorption-type quartz pad is fixed to the palm part by a quartz fixing block and a first spring clip.

[0014] The absorbent quartz pad has ears on opposite sides, each ear having an absorbent quartz pad fixing hole. The palm portion has a through hole corresponding to the absorbent quartz pad fixing hole. The quartz fixing block has a first fixing post and a second fixing post, the second fixing post having a groove. When fixing the absorbent quartz pad, the quartz fixing block passes through the absorbent quartz pad fixing hole and the through hole. The first spring clip includes a first base and a first spring wire. The first spring wire includes a first wire portion and a second wire portion. The first wire portion extends along the extension direction of the first base. The second wire portion is connected to the first wire portion and forms an angle with the first wire portion. The first spring clip is inserted through a first base adapter hole on the palm portion and travels along the groove in the palm portion, passing through the groove of the quartz fixing block. The first base of the first spring clip is inserted into the first base adapter hole.

[0015] The quartz support pad is fixed to the finger by a second spring clip;

[0016] The quartz support pad has a first support column and a second support column. The second support column has a groove. When fixing the quartz support pad, the quartz support pad passes through the fixing hole of the quartz support pad provided on the finger. The second spring clip includes a second base and a second spring steel wire. The second spring steel wire includes a third steel wire portion and a fourth steel wire portion. The third steel wire portion extends along the extension direction of the second base. The fourth steel wire portion is connected to the third steel wire portion and forms an angle with the third steel wire portion. The second spring clip is inserted through the second base adapter hole provided on the finger and travels along the groove provided in the finger, passing through the groove of the quartz support pad. The second base of the second spring clip is inserted into the second base adapter hole.

[0017] In one embodiment of this disclosure, the arm adapter unit includes a heat dissipation structure and a heat dissipation extension block. The heat dissipation structure is disposed between the robot's arm and the heat dissipation extension block, and the heat dissipation extension block is connected to the palm portion.

[0018] In one embodiment of this disclosure, the heat dissipation structure has a multi-layer sheet-like heat dissipation structure.

[0019] In one embodiment of this disclosure, the finger unit includes two fingers arranged in parallel, suitable for use with a precalibrator.

[0020] In the embodiments of this disclosure, the quartz support pad is fixed to the finger by a spring steel wire, and the adsorption-type quartz pad is fixed to the palm part by the cooperation of the spring steel wire and the quartz fixing block. This provides sufficient expansion space for each component, avoiding damage to the finger unit caused by the thermal expansion and contraction of the screws during heating, as is common in existing technologies. Furthermore, the quartz support pad and the adsorption-type quartz pad can be fixed by simply inserting and removing the screws, which is simpler and more reliable than screw fixing. In addition, the palm part, the finger, the adsorption-type quartz pad on the palm part, the quartz fixing block for fixing the adsorption-type quartz pad, the quartz support pad, the spring clips for fixing the quartz fixing block, and the spring clips for fixing the support quartz pad are all made of high-temperature resistant materials, which can meet the requirements for normal use in high-temperature chambers (e.g., 420°C). By setting up a heat dissipation structure and heat dissipation extension block between the robot's arm and finger unit (i.e., end effector), the heat conduction efficiency between the finger unit and the robot's arm is increased, the heat dissipation efficiency is improved, the heat transferred from the finger unit to the robot's arm is significantly reduced, the heat damage to the components in the robot's arm is effectively prevented, and the service life of the robot is extended.

[0021] At least one embodiment of this disclosure also provides a robot suitable for high-temperature processes, the robot including the end effector described above for high-temperature processes.

[0022] The robot for high-temperature processes according to embodiments of this disclosure can cooperate with a pre-calibrator to improve transport efficiency. It can also ensure stress concentration on the deformed wafer after heating, reducing defects after wafer cooling. Furthermore, it can provide good support for the heated wafer, reducing warpage. Simultaneously, it can prevent damage to the end effector due to thermal expansion and contraction. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings of the embodiments will be briefly described below. Obviously, the drawings described below only relate to some embodiments of this disclosure and are not intended to limit this disclosure.

[0024] Figure 1 A schematic diagram of a gripping robotic arm known to the inventor is shown.

[0025] Figure 2 A schematic diagram of a known adsorption-type robotic arm is shown.

[0026] Figure 3 A schematic diagram of the structure of a robot end effector suitable for high-temperature environments according to an embodiment of the present disclosure is shown;

[0027] Figure 4The structure of an adsorption-type quartz pad according to one embodiment of the present disclosure is schematically shown;

[0028] Figure 5 The structure of a quartz fixing block according to an embodiment of the present disclosure is schematically shown;

[0029] Figure 6 The structure of a spring clip according to an embodiment of the present disclosure is schematically shown; and

[0030] Figure 7 The diagram schematically illustrates the working state of a robot end effector in conjunction with a pre-calibrator according to an embodiment of the present disclosure. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0032] At least one embodiment of this disclosure provides a robotic end effector suitable for high-temperature environments, comprising an arm adapter unit and a finger unit, wherein,

[0033] The arm adapter unit connects the robot's arm and the finger unit; and

[0034] The finger unit is integrally formed from ceramic material and includes a palm part and fingers. The palm part is connected to the arm adapter unit. An adsorption quartz pad is fixed on the palm part. The fingers extend outward from the palm part, and a quartz support pad is provided at the end of the fingers away from the palm part.

[0035] In the robotic end effector suitable for high-temperature environments according to this disclosure, a large suction-type quartz pad is provided only in the palm portion. This ensures that the force on the heated, deformed wafer is concentrated during wafer handling, preventing the wafer from being subjected to forces in multiple directions after cooling, which could lead to cracks. The quartz support pad on the finger and the suction-type quartz pad support the wafer together during wafer handling, improving support stability and preventing deformation of the wafer in a softened state at high temperatures.

[0036] Figure 3 A schematic diagram of a robotic end effector suitable for high-temperature environments according to an embodiment of the present disclosure is shown.

[0037] like Figure 3 As shown, a robotic end effector suitable for high-temperature environments includes an arm adapter unit 39 and a finger unit. The arm adapter unit 39 connects between the robot's arm and the finger unit. The finger unit is configured to hold the wafer during wafer pick-up and drop. In one embodiment of this disclosure, the finger unit is integrally formed from a ceramic material and includes a palm portion 38 connected to the arm adapter unit 39 and two fingers 41, 42 extending from the palm portion. The palm portion 38 is fixed with an absorbent quartz pad 33. Of course, in one embodiment of this disclosure, the palm unit may include only one finger.

[0038] Figure 4 The structure of an absorbent quartz pad 33 according to one embodiment of the present disclosure is schematically shown. Figure 4 As shown, the adsorption-type quartz pad 33 has an adsorption plane 401 and a wafer contact plane 403. The adsorption plane 401 is provided with pores 402, which are connected to a vacuum device, creating a vacuum at the adsorption plane. During wafer handling, the wafer can be adsorbed onto the wafer contact surface 403. The adsorption-type quartz pad is made of quartz material and has high-temperature resistance, making it suitable for high-temperature environments. In the embodiments according to this disclosure, the adsorption-type quartz pad 33 has a large adsorption area, allowing wafer handling to be completed with only one adsorption quartz pad. In this case, the number of pores 402 can be determined based on the area of ​​the wafer and the size of the adsorption surface. Figure 4 The image shows an example of an adsorption quartz pad 33 with two pores 402 on its adsorption surface 401. In actual implementation, the size of the adsorption surface can be set according to the area of ​​the wafer to be picked up or placed, and the number of pores on the adsorption surface can also be set according to the area of ​​the wafer.

[0039] The adsorption quartz pad 33 also has ears 405 extending from two opposite sides, with fixing holes 405 provided on the ears. The quartz fixing block 32 passes through the fixing holes 405 and then through the fixing holes provided on the palm part, and is fixed by spring clips.

[0040] Figure 5 The structure of the quartz fixing block 32 is schematically shown. (As shown) Figure 5 As shown, the quartz fixing block 32 includes a first fixing post 3201 and a second fixing post 3202. The diameter of the second fixing post 3202 is smaller than that of the first fixing post 3201, and it is used to pass through the fixing hole 405. A groove 3203 is formed along the circumference of the second fixing post 3202. The groove 3203 is used to accommodate the spring clip to fix the quartz fixing block 32.

[0041] like Figure 3As shown, the quartz fixing block 32 and the quartz support pads 34 and 36 are all fixed to the finger unit by spring clips 35. Specifically, the quartz fixing block 32 is fixed to the palm part 38 by spring clips 35, the quartz support pad 34 is fixed to the finger 41 by spring clips 35, and the quartz support pad 36 is fixed to the finger 42 by spring clips 35.

[0042] Figure 6 The structure of the spring clip 35 is schematically shown. The spring clip 35 includes a base 3501 and a spring wire 3502. The base 3501 includes a first base portion with a larger diameter (the left side of the base shown in the figure) and a second base portion with a smaller diameter (the right side of the base shown in the figure). An adapter hole matching the shape of the base portion is provided on the palm portion for fitting. Because the base is made of metal, its diameter can be smaller than the diameter of the adapter hole. This prevents the expanded base from supporting the adapter hole and affecting the palm portion during thermal expansion. The spring wire 3502 includes a first wire portion and a second wire portion. The first wire portion is connected to the second base portion and extends along the centerline of the second base portion. The angle between the second wire portion and the first wire portion is α.

[0043] Taking the spring clip 35 for fixing a quartz fixing block as an example, this explains how the spring clip fixes a quartz fixing block or quartz support block. When fixing an absorbent quartz pad with a quartz fixing block, first place the absorbent quartz pad in a suitable position. Then, pass the quartz fixing block through the fixing hole of the absorbent quartz pad and through the fixing hole located on the palm part. Next, pass the spring wire through the adapter hole. A groove is provided on the back of the palm part, extending from the adapter hole to the fixing hole. The spring wire travels along the groove from the adapter hole to the fixing hole. At this point, the spring wire enters the groove on the quartz fixing block and exits from the side of the quartz fixing block away from the adapter hole. As the first part of the wire begins to enter the adapter hole, the second part of the wire is already engaged in the groove of the quartz fixing block. Due to the angle formed between the first and second parts of the spring wire, the spring wire begins to deform. As the first part of the wire enters the adapter hole, the spring wire applies a force to the quartz fixing block, fixing it in the fixing hole.

[0044] The quartz support pad has a structure similar to that of a quartz fixing block. The quartz support pad has a first support column and a second support column, which are connected and share the same axis. The diameter of the first support column is larger than the diameter of the second support column. A groove is provided on the second support column. When fixing the quartz support pad, it passes through a quartz support pad fixing hole provided on the ceramic finger. The second spring clip includes a second base and a second spring wire. The second spring wire includes a third wire portion and a fourth wire portion. The third wire portion extends along the extension direction of the second base, and the fourth wire portion connects to the third wire portion and forms an angle with it. The second spring clip is inserted through a second base adapter hole provided on the finger and travels along the groove provided in the finger, passing through the groove of the quartz support pad. The second base of the second spring clip is inserted into the second base adapter hole.

[0045] The quartz support pad is fixed to the finger using spring steel wire, and the adsorption quartz pad is fixed to the palm using the cooperation of the spring steel wire and the quartz fixing block. This provides ample expansion space for each component, avoiding damage to the finger unit caused by the thermal expansion and contraction of screws during heating, as is common in existing technologies. Furthermore, the quartz support pad and adsorption quartz pad can be fixed by simply inserting and removing them, which is simpler and more reliable than screw fixing. In addition, the palm, fingers, adsorption quartz pad on the palm, quartz fixing block for fixing the adsorption quartz pad, quartz support pad, spring clips for fixing the quartz fixing block, and spring clips for fixing the support quartz pad are all made of high-temperature resistant materials, allowing for normal use in high-temperature chambers (e.g., 420°C).

[0046] like Figure 3 As shown, the arm adapter unit 39 connects the robot's arm (not shown) and the finger unit, and includes a heat dissipation structure 31 and a heat dissipation extension block 39. The heat dissipation structure 31 is disposed between the robot's arm and the heat dissipation extension block 39, and the heat dissipation extension block is connected to the palm portion 38. In one embodiment of this disclosure, the heat dissipation structure 31 has a multi-layer sheet-like heat dissipation structure, as shown in the figure. Figure 3 As shown. Of course, the heat dissipation structure 31 can also adopt other structural forms.

[0047] By setting up a heat dissipation structure and heat dissipation extension block between the robot's arm and finger unit (i.e., end effector), the heat conduction efficiency between the finger unit and the robot's arm is increased, the heat dissipation efficiency is improved, the heat transferred from the finger unit to the robot's arm is significantly reduced, the heat damage to the components in the robot's arm is effectively prevented, and the service life of the robot is extended.

[0048] In one embodiment of this disclosure, the finger unit includes two ceramic fingers. These two ceramic fingers are normally positioned so that, during wafer handling, the center of the wafer can be positioned between the two ceramic fingers. In this case, the end effector of the robot for high-temperature processes according to this disclosure can cooperate with a pre-calibrator, which is a device capable of calibrating the wafer center and locating wafer notches. After the pre-calibrator calibrates the wafer center, the robot can drive the end effector to move under the wafer, creating a vacuum on the surface of the adsorption quartz pad, and adsorbing the wafer whose center has been calibrated. A schematic diagram of its working state is shown below. Figure 7 As shown.

[0049] For ease of reading and understanding, Figure 7 Zhongyu Figure 3 The same components shown are referred to by the same reference numerals. Figure 7 As shown, the pre-calibrator 70 includes a calibration support 71 that protrudes from the base and is configured to support the wafer 40 and calibrate its center. This creates a space between the wafer 40 and the base, allowing the end effector's finger unit to enter and exit this space when the robot picks up and places the wafer, facilitating wafer handling and improving transport efficiency.

[0050] The end effector of the robot for high-temperature processes according to embodiments of this disclosure can be used in conjunction with a pre-calibrator, improving production efficiency. Actual measurements show that following the path of "retrieving wafers at the first station → placing wafers in the high-temperature chamber, retrieving wafers after heating → placing them on the pre-calibrator for calibration, retrieving wafers after calibration → placing them at the second station," the process time in the high-temperature chamber is approximately two minutes, and the robot can achieve a transport efficiency of 20 wafers per hour.

[0051] At least one embodiment of this disclosure also provides a robot for high-temperature processes, the robot including the end effector described above for high-temperature processes.

[0052] The robot for high-temperature processes according to embodiments of this disclosure can cooperate with a pre-calibrator to improve transport efficiency. It can also ensure stress concentration on the deformed wafer after heating, reducing defects after wafer cooling. Furthermore, it can provide good support for the heated wafer, reducing warpage. Simultaneously, it can prevent damage to the end effector due to thermal expansion and contraction.

[0053] The above description is merely a preferred embodiment of this disclosure. The embodiments are not intended to limit the scope of patent protection of this disclosure. Therefore, any equivalent structural changes made based on the description and drawings of this disclosure should also be included within the scope of protection of this disclosure.

Claims

1. A robotic end effector for a wafer transfer system, suitable for high-temperature environments, the robotic end effector comprising an arm adapter unit and a finger unit, wherein, The arm adapter unit is connected between the robot's arm and the finger unit; as well as The finger unit is integrally formed from ceramic material and includes a palm part and fingers. The palm part is connected to the arm adapter unit. An adsorption quartz pad is fixed on the palm part. The fingers extend outward from the palm part, and a quartz support pad is provided at the end of the fingers away from the palm part. The adsorption-type quartz pad has an adsorption surface and a wafer contact surface. The adsorption surface is provided with pores connected to a vacuum device. The height of the quartz support pad relative to the finger is equal to the height of the wafer contact surface relative to the palm portion. The adsorption-type quartz pad is fixed to the palm part by a quartz fixing block and a first spring clip. The absorbent quartz pad has ears on opposite sides, each ear having a fixing hole. The palm portion has a through hole corresponding to the fixing hole. The quartz fixing block has a first fixing post and a second fixing post, the second fixing post having a groove. When fixing the absorbent quartz pad, the quartz fixing block passes through the fixing hole and the through hole. The first spring clip includes a first base and a first spring wire. The first spring wire includes a first wire portion and a second wire portion. The first wire portion extends along the extension direction of the first base. The second wire portion connects to the first wire portion and forms an angle with it. The first spring clip is inserted through a first base adapter hole on the palm portion and travels along the groove in the palm portion, passing through the groove of the quartz fixing block. The first base of the first spring clip is inserted into the first base adapter hole. The quartz support pad is fixed to the finger by a second spring clip; The quartz support pad has a first support column and a second support column. The second support column has a groove. When fixing the quartz support pad, the quartz support pad passes through the fixing hole of the quartz support pad provided on the finger. The second spring clip includes a second base and a second spring steel wire. The second spring steel wire includes a third steel wire portion and a fourth steel wire portion. The third steel wire portion extends along the extension direction of the second base. The fourth steel wire portion is connected to the third steel wire portion and forms an angle with the third steel wire portion. The second spring clip is inserted through the second base adapter hole provided on the finger and travels along the groove provided in the finger, passing through the groove of the quartz support pad. The second base of the second spring clip is inserted into the second base adapter hole.

2. The robot end effector according to claim 1, wherein, The finger unit includes two fingers arranged in parallel, suitable for use with a pre-calibrator.

3. The robot end effector according to claim 1 or 2, wherein, The arm adapter unit includes a heat dissipation structure and a heat dissipation extension block. The heat dissipation structure is disposed between the arm of the robot and the heat dissipation extension block, and the heat dissipation extension block is connected to the palm part.

4. The robot end effector according to claim 3, wherein, The heat dissipation structure has a multi-layered sheet-like heat dissipation structure.

5. A robot for a wafer transport system, suitable for high-temperature processes, wherein, The robot includes the robot end effector as described in any one of claims 1 to 4.

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