TWI223372B - Eccentric correction cassette for wafer - Google Patents

Abstract

The present invention provides an eccentric correction cassette for wafer, which is used in the wafer conveying equipment to provide the function of correcting center position offset for wafer placement. The eccentric correction cassette for wafer includes a cover plate, a plurality of first wafer correction plates, a plurality of second wafer correction plates, a plurality of spacer rings, a bottom rod and a bottom plate, and, a first cassette seat and a second cassette seat. The eccentric correction cassette for wafer is to correct the center position offset for the wafer placement arising from the process of wafer sucking and putting by the vacuum sucking device, which provides the transition function between robots for the two-way transmission of the vacuum sucking device and the contact atmosphere robot at the wafer bottom, and also makes the load lock chamber having the function of storing a lot of wafers before processing and after processing, so that the robot can access the wafer at a suitable time.

Description

1223372 V. Description of the invention (1) [Technical field to which the invention belongs] The wafer eccentricity correction cassette of the present invention is a device for correcting the deviation of the center position of wafer placement in a wafer conveying device, especially It can correct the deviation of the center position of the wafer placed during the vacuum suction device. [Previous technology]% The wafer conveying equipment of the chemical vapor deposition process of the conventional wafer cassette is shown in the first figure. The wafer before processing is sent into the cassette G first; Η It is transported into the crystal cassette A in the load lock chamber B (Load Lock Chamber), and the wafer Η is sucked from the cassette A by a manually operated vacuum adsorption device E, and then the wafer is placed in a wafer carrier tray. Inside the circular groove D of C, and close the upper cover of the wafer carrier tray. After the high temperature (about 140 ° C) process, after the temperature drops to a range that the human body can withstand, open the upper cover, and then manually Operate the vacuum adsorption device E to take the wafer out of the carrier tray and place it in the cassette. The atmospheric robot arm F sends the wafer back to the cassette G, and then continues to the next step where the wafer is automatically transported. ) As shown in the second figure, during the process of placing the wafer stack into the circular groove by the vacuum suction device E, because the pressure of the gas at the bottom of the wafer stack is higher than the upper part, an upward pressure J is generated. The lateral force component K of the combined force J and wafer gravity I will cause a lateral displacement of the wafer Η, causing a phenomenon of drift (as shown in the third figure). Because this is a random process, the position where the wafer stack is placed in the circular groove D is different each time. Therefore, when the wafer stack is processed, the vacuum adsorption device E returns the wafer stack to the cassette holding chamber B. When the wafer cassette A is known, the placement position is different from the original position, that is, the center position of the wafer stack is shifted.

Page 81222332 V. Explanation of the invention (2) The wafer stack is returned to the cassette G by the atmospheric mechanical arm F. The position where the wafer stack is placed in the cassette G is also different from the original. This difference in position will not be conducive to subsequent Automatic conveying. Therefore, this position difference must be corrected to an acceptable range, so that the next step of the wafer can be automatically transported. Furthermore, the manual operation of the vacuum adsorption device to transport the wafers also easily causes the wafers to be contaminated by dust particles, and the waiting time for cooling down is too long, which reduces the lack of production efficiency. [Summary of the Invention] "Technical Problems to Be Solved" The technical problem to be solved by the wafer eccentricity correction cassette of the present invention is that when a vacuum suction device places a wafer in a circular groove of a wafer carrier disk, During the wafer placement process, the pressure of the gas at the bottom of the wafer is greater than that of the upper part. The combined force and gravity will cause the wafer to move laterally and cause drift, so the wafer is placed in the wafer recess. The position of the slot is different each time, so when the wafer processing is completed, the vacuum suction device returns the wafer to the conventional wafer cassette in the cassette carrying chamber, the center position of the wafer stack has shifted, so its There is a problem that the placement position is different from the original position. "Technical Means for Solving the Problem" The technical means for solving the foregoing problems of the present invention is to design a wafer eccentricity correction cassette capable of correcting the deviation of the center position of the wafer placement, instead of the conventional crystal round cassette. The wafer eccentricity correction cassette of the present invention has a first wafer correction plate and a second wafer correction plate.

1223372 V. Description of the invention (3) The wafer correction plate is divided into wafer placement grooves. The first wafer is not provided with an arc. The wafer placement correction plate and the circular placement groove formed by the corner are in the same position. With the device, the crystal placement position will be chamfered by the action of correcting the plate and the first notch, the purpose of penetrating the notch through the notch is to complete the wafer placement, and the wafer in the range of the positive cassette has the wafer. When vacuum suction is used, the wafer is penetrated through the placement groove, and in addition, the wafer is inserted upward or upward, and a circular groove is formed between the arc grooves to place the wafer. The circular grooves of the two wafer correction plates are respectively provided with a conical surface and the gravity of the wafer itself. However, the center positions of the wafers are not shifted. Therefore, when the wafer is different each time, but when the wafer processing circle is returned to the cassette carrying chamber, the wafer eccentricity will be the same as the original position or the crystal formed between the two wafer correction plates can be accepted. The circular placement is for the laser light emitted by the laser light source to pass to detect whether there is a wafer in the wafer placement slot to provide the space that the robotic arm can take when placing the wafer. "Effects of the prior art" Comparing conventional wafer cassettes, the wafer eccentricity correction cassette of the present invention has the following effects: The first effect is that when a vacuum adsorption device is used to remove a wafer from a cassette lock chamber (Load Lock Chamber) The wafer eccentricity correction cassette is moved into the circular groove of the wafer carrier _ tray for related process processing. After the wafer is processed, the vacuum adsorption device moves the wafer from the circular groove of the wafer carrier tray back to the wafer. The wafer eccentricity correction card H in the cassette carrying room, in the above process, there may be no difference in the position error between the wafer placement position and the original position or within an acceptable range

Page 10 1223372 V. Description of Invention (4). The second effect is that the wafer eccentricity correction cassette of the present invention is a new low-cost and reliable solution. The third effect is that the wafer eccentricity correction cassette of the present invention can provide a robot arm transfer function, so that the vacuum adsorption device and the atmospheric robot arm or other types of robot arms can transfer in both directions. The fourth effect is that the wafer eccentricity correction cassette of the present invention can provide the cassette loading chamber with a function of storing wafers before and after processing, so that the robot arm can access the wafers at an appropriate time. A fifth effect is that the wafer eccentricity correction cassette of the present invention can provide a wafer placement slot to be irradiated by an optical detection device to determine whether a wafer exists in the wafer placement slot. The sixth effect is that the bottom bar design under the wafer eccentricity correction cassette of the present invention can generate a signal that the wafer eccentricity correction cassette of the present invention exists. [Embodiment] The technical characteristics of the wafer eccentricity correction cassette 1 of the present invention will be better understood with the illustration. The fourth figure is a schematic diagram of the chemical vapor deposition process equipment for adding the wafer eccentricity correction cassette 1 of the present invention, in which the wafer 8 before processing is sent into the cassette 7 first; then the wafer 8 is transported by the atmospheric robot 6 Enter the wafer eccentricity correction cassette 1 in the load lock chamber 2 (Load Lock Chamber), and then use a vacuum suction device 5 (such as a front suction wafer picking arm) to suck the wafer 8 and place it in the wafer Relevant process processing is performed in the circular groove 4 of the carrier plate 3. After processing, then

1223372 V. Description of the invention (5) The wafer 8 is transported back to the eccentricity correction cassette 1 in the cassette carrying chamber 2 by the vacuum adsorption device 5 and then the wafer 8 is returned to the cassette 7 by the atmospheric robot 6 and then continued The wafer 8 in the next step is automatically transported. '^ During the process of placing the wafer 8 into the circular groove 4 by the vacuum adsorption device 5, the pressure of the gas at the bottom of the wafer 8 is greater than that of the upper portion. The combined force and gravity will cause the circle 8 to be displaced laterally. , Causing the phenomenon of drift. Because this is a random & process, the position of the Japanese yen 8 placed in the circular groove 4 is different each time, but after the wafer processing is completed, the vacuum adsorption device 5 returns the wafer 8 to the card carrier ^ 2 When the M wafer wafer eccentricity correction cassette 1 is placed, the placement position will be different from the original position, that is, the center position of the wafer 8 is not shifted. The circle 8 is returned to the cassette 7, and the position of the wafer 8 placed in the cassette 7 is also the same as the original, so the wafer 8 can be automatically transported to the next step. _ a The fifth, sixth and seventh pictures are a perspective view, a three-dimensional inverted view and an exploded view of the creative wafer eccentricity correction cassette. The main components include a cover plate 11 and a plurality of first wafer correction plates 1 3. A plurality of second wafer straightening plates 14, a plurality of spacer rings 16, a plurality of first cassette bases 18 and a plurality of second cassette bases 19, and a bottom bar 20 and a bottom plate 12. The cover plate 11 is provided on the top of the wafer eccentricity correction cassette 1; the bottom plate 丨 2 is provided on the bottom of the wafer eccentric end positive card E 1 0, the first wafer correction plate 13 and the second plate of the wafer bridge 14 is located between the cover plate n and the bottom plate 12; the spacer ring is divided between the first wafer alignment plate 13, the second wafer alignment plate 14, the bottom plate 12, and the cover plate. A 'bottom bar 20' between the wafer alignment plates 13 and a plurality of second wafer alignment plates 14 is disposed below the base plate 12. The assembly method of the wafer eccentricity correction card e! Of the present invention is to first assemble the second card g

Page 12 LZZ33n V. Description of the invention (6) The seat 1 9 is a screw cassette loading chamber 9. At the bottom plate I2, the second cassette base 19 is used at an appropriate height and the bottom plate ^ is a cassette lifting device ^ 丨 ㈢ Take ... not shown in the figure), make the degree. Then Jiang Guangmu's slot "can reach the high screw of the robot arm to grab the wafer 8" and put one end of the ~ ^^ 2 0 into a first-^ box base 18, and then use the box to carry 0 boxes The base 18 is locked to the bottom plate 12. The purpose of the bottom bar 20 is to press the sensor (not shown in the figure) of the cassette lifting device of the hairpin to produce the signal of the existence of the sun eccentricity correction card E 丨. . Pass one end of the hemp Z ^ screw 1 5 and lock the nut 17, and insert the other end of the screw 15 into I * general # preset through hole U 1 and tighten with the nut 1 7, and then the spacer ring 16 sets, s force 1 1 h dry 1 5 and locking nut 17; then pass the tm of the first crystal correction plate 1 3 @the through hole n 1 of the first wafer correction plate 1 4 through the screw 15 and tighten with screw = I f, then set the spacer ring 16 sets of each screw 15 and locking nut 17; ^ analogy, the remaining first wafer alignment plate 14 and second wafer alignment plate 15 = Assembly. During the assembly process, a special fixture must be supplemented to ensure the roundness of the wafer placement slot 10 formed by the first 1 ^ 1 straightening plate 14 and the second wafer straightening plate 15. And concentricity. The function of the spacer ring 6 is to keep the interval between the upper and lower wafer placement grooves 10 constant. Finally, the through hole i 丨 丨 of the cover plate 丨 丨 is passed through the screw 丄 5 and locked with a screw 1 7 to complete the wafer eccentricity correction cassette ^ assembly of the present invention. As shown in the seventh figure, the first wafer straightening plate 13 and the second wafer straightening plate 14 are respectively provided with an arc groove i 3 2 and an arc groove 丨 4 2, and the arc groove i 3 2 A circular wafer placement groove 丨 0 is formed between the arc groove 1 4 2 and the wafer placement groove 10. The wafer placement groove 10 can place the wafer 8. At the same time, the vacuum adsorption device 5 and the atmospheric robot arm 6 can be placed. The function of the robot arm or other types of two-way transmission and storage of the wafer 8 before and after processing 'allows the robot arm to access the wafer 8 at an appropriate timing.

1223372 V. Description of the invention (7) As shown in the eighth figure, the arc groove 1 3 2 and the arc groove 1 4 2 of the first wafer correction plate 13 and the second wafer correction plate 1 4 are respectively With chamfers 1 3 3 and chamfers 1 4 3, using the conical surface formed by chamfers 1 3 3 and chamfers 1 4 3 and the gravity of the wafer 8 itself, the wafer 8 can be placed in the wafer When the slot is 10, its center position will not be shifted. Therefore, although the position of the wafer 8 placed in the circular groove 4 is different each time, when the wafer 8 is processed, the vacuum adsorption device 5 returns the wafer 8 to the wafer eccentricity in the cassette carrying chamber 2 When correcting cassette 1, its placement position will be the same as the original position. As shown in the ninth figure, the wafer placement groove 10 formed between the first wafer alignment plate 13 and the second wafer alignment plate 14 has a through gap 1 01, the purpose of which is to provide lightning. The laser light emitted from the light source 9 passes through the through gap 1 (Π) of the wafer placement slot 10 to detect whether there is a wafer 8 in the wafer placement slot 10, and the through gap 1 01 also provides the atmosphere When the robot arm 6 picks up and places the wafer 8, the space required for the upward or downward movement can be performed. The present invention has been described in detail above, but the above is only a preferred example of the present invention. Limiting the scope of implementation of the present invention, all equivalent changes and modifications made according to the scope of the present application should still fall within the scope of the patent of the present invention.

Page 14 1223372 Brief description of the diagram The first diagram is a schematic diagram of a wafer conveying device for a conventional chemical vapor deposition process of a wafer cassette. The second figure is a schematic diagram of a conventional chemical vapor deposition process equipment. The third figure is a schematic diagram of lateral drift caused by placing a wafer in a conventional chemical vapor deposition process equipment. The fourth figure is a schematic diagram of a chemical vapor deposition process equipment equipped with the wafer eccentricity correction cassette of the present invention. The fifth figure is a three-dimensional view of the wafer eccentricity correction card. The sixth figure is a three-dimensional inverted view of the wafer eccentricity correction cassette. The seventh figure is an exploded view of the components of the wafer eccentric bridge positive cassette. The eighth figure is a schematic diagram of a wafer placement groove composed of a first wafer straightening plate and a second wafer straightening plate. The ninth figure is a schematic diagram of optical detection. [Symbol description of wafer eccentricity correction cassette components of the present invention] (I) Wafer eccentricity correction cassette (II) Cover plate (1 2) Base plate (1 3) First wafer correction plate (132) Arc groove (133) ) Chamfer (14) Second wafer correction plate (142) Arc groove

Page 151222332 Brief description of the diagram (1 4 3) Chamfer (1 5) Screw (1 6) Spacer ring (1 7) Nut (111) Through hole (18) First cassette base (19) Second Cassette base (2 0) Bottom post (2) Cassette carrying chamber (3) Wafer carrying tray (4) Wafer groove (5) Vacuum suction device (6) Atmospheric robot arm (7) Cassette (8) Wafer (9) Laser light source (9 1) Laser light detection device (1 0) Through hole for wafer placement slot (101) [Symbol description of chemical vapor deposition process equipment components equipped with conventional wafer cassettes] ( A) Known wafer cassette

Page 161222332 Brief description of the drawing (B) Card E loading chamber (C) Wafer carrier disk (D) Wafer groove (E) Vacuum suction device (F) Atmospheric robot arm (G) Cassette (H) Crystal Circle (I) Wafer Gravity (J) Air pressure combined force (K) Lateral force component

Claims (1)

1223372 VI. Scope of patent application 1. A wafer eccentric front plate and a plurality of first bottom bars; the cover plate is provided on the bottom plate and the rectified cassette, and includes a cover plate and a plurality of first wafer straightening plates; Two wafer correction plates, a plurality of spacer rings, a bottom plate and a top of the wafer eccentric bridge positive card Kuang, the bottom of the wafer eccentric correction card Kuang, and the bottom plate of the spacer plate, the first correction plate and the bottom. According to the base . 3. According to the fourth. According to the first and second wafer straightening plates, the first wafer straightening plate and the second wafer straightening plate are provided between the cover plates; Between the cover plates and between the plurality of first wafers and the second wafer alignment plates; below the bottom plate. The wafer eccentricity correction cassette described in the first item of the scope, wherein a plurality of first cassette bases and a plurality of second cassette bottom rings are respectively provided between the two wafer ends and the complex rods are arranged on the patent application board. The wafer eccentricity correction cassette described in the second patent application scope is provided on the lower edge, and one of the cassette bases is provided with the bottom bar. The wafer eccentricity correction cassette described in item 1 of the patent application scope, wherein a through gap is formed between a wafer correction plate and the second wafer correction plate 5. According to the wafer eccentricity described in item 1 of the patent application scope An alignment cassette, wherein the first wafer alignment plate and the second wafer alignment plate are respectively provided with arc grooves. 6. The wafer eccentricity correction cassette according to item 5 of the scope of the patent application, wherein the arc grooves of the first wafer alignment plate and the second wafer alignment plate are respectively provided with chamfers. Page 18