JP2008103379A - Manufacturing method of semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique capable of reducing generation of foreign matters in a process of conveying semiconductor wafers, using hand. <P>SOLUTION: A rod 17 is fixed on a piston 16, a first pressure line 19 connected to a first space 18 and a second pressure line 21 connected to a second space 20 are provided to a cylinder 15, and a screw hole 22 and a screw 23 mated with the screw hole 22 are provided on the piston 16. The first space 18 is evacuated from the first pressure line 19 with the second pressure line 21 closed, thereby moving the piston 16 to allow a movable portion 13 to move, and air is taken from the second pressure line 21 into the second space 20 with the first pressure line 19 closed, thereby moving the piston 16 to allow the movable portion 13 to move. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor device manufacturing technique, and more particularly, to a semiconductor device manufacturing method including a process of transferring a semiconductor wafer using a hand of a robot for transferring a semiconductor wafer (hereinafter referred to as “transfer robot”). And effective technology.

  The semiconductor wafer is preferably used to form a chip of an integrated circuit, and from which foreign matters such as dust are removed because it affects the manufacturing yield. A so-called pre-process for manufacturing a semiconductor device is generally performed in a clean room, and for various processes, a semiconductor wafer is transported between apparatuses performing the processes.

  The semiconductor wafer is transferred by, for example, a transfer robot provided in a clean room, and is transferred by being clamped by a hand provided at the tip of an arm of the transfer robot. For this hand, a cylinder driving clamp method, a dropping method, a Bernoulli method, or the like is used.

Japanese Patent Application Laid-Open No. 2000-77497 (Patent Document 1) discloses a technique related to a robot having a pneumatic cylinder as a semiconductor wafer clamping device.
JP 2000-77497 A

  The dropping method is, for example, a method in which a semiconductor wafer is dropped between the receiving portions on a stage provided with a plurality of receiving portions on the edge. However, the level of the semiconductor wafer is difficult to be obtained, and when the semiconductor wafer is corrected, it cannot be corrected accurately. In addition, an inertial force may be applied during high-speed conveyance, and the semiconductor wafer may be displaced.

  The Bernoulli method is a method of chucking a semiconductor wafer in a non-contact manner using the Bernoulli effect. However, when a large amount of nitrogen gas is blown onto the wafer surface when the semiconductor wafer is chucked, particulate contamination or the like may adhere to the semiconductor wafer surface.

  Also, the cylinder drive clamp system is composed of, for example, a pneumatic cylinder attached to the arm of the transfer robot. The rod of the pneumatic cylinder presses the side surface of the semiconductor wafer and presses the semiconductor wafer against the receiving part of the opposing stage. This is a clamping method. However, there are problems that metal foreign matter is generated from the rod of the cylinder, foreign matter is scattered due to air leakage from a joint or the like, and foreign matter is generated due to friction of the clamp link portion.

  Conventionally, the size of foreign matter adhering to a semiconductor wafer has been measured and evaluated with a limit of 0.1 μm. However, with the miniaturization of the semiconductor wiring, the size of the foreign material is also reduced to 0.1 μm or less, and 0.05 μm is required. Therefore, for example, it is essential to improve the cleanliness of a semiconductor wafer transfer hand used in a wafer sorter or the like.

  Therefore, as a countermeasure against dust generation from the cylinder, it is common to use a method of covering the entire object and sucking up dust generated by exhausting. In this case, it is necessary to add a structure other than the original mechanism of the hand, leading to an increase in the size of the hand and an increase in manufacturing cost of the semiconductor device.

  An object of the present invention is to provide a technique capable of reducing the generation of foreign matters in a process of transporting a semiconductor wafer using a hand.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  A method of manufacturing a semiconductor device according to the present invention uses a hand having a movable portion and a receiving portion provided at an edge of a stage, and (a) a semiconductor mounted on a stage by moving the movable portion in the direction of the stage. A step of clamping the wafer by the movable portion and the receiving portion, and (b) a step of unclamping the semiconductor wafer mounted on the stage by moving the movable portion in a direction opposite to the stage side. The rod is fixed to the piston. The cylinder has a first pressure line connected to a first space formed by the inner surface of the cylinder and the first surface of the piston, and a second surface paired with the inner surface of the cylinder. And a second pressure line connected to the second space formed by the through hole, the piston having a through hole connecting the first space and the second space, a screw fitted in the through hole, , Is provided. Here, in the step (a), the first space is evacuated from the first pressure line with the second pressure line closed, thereby moving the piston and moving the movable part. Then, when the first pressure line is closed, air is flown into the second space from the second pressure line, so that the piston moves and the movable portion moves.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  According to the semiconductor device manufacturing technique of the present invention, it is possible to reduce the generation of foreign matters in the process of transporting a semiconductor wafer using a hand.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

  First, a hand of a robot (transport robot) for transporting a semiconductor wafer used in a semiconductor device manufacturing process according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view schematically showing the hand 1 in the present embodiment. 2 is a cross-sectional view taken along line A-A ′ of FIG. 1. FIG. 3 is a plan view schematically showing the transfer robot having the hand 1. In FIG. 1, the semiconductor wafer W is shown in a transparent state.

  As shown in FIGS. 1 and 2, the hand 1 has a stage 12 on which a semiconductor wafer W is mounted, and a movable part 13 and a receiving part 14 provided on the edge of the stage 12. The movable portion 13 is a tip portion of a rod 17 extending from the first surface 16 a side of the piston 16 that reciprocates in the cylinder 15.

  The rod 17 is fixed to the piston 16. The cylinder 15 has a first pressure line 19 connected to a first space 18 formed by the inner surface of the cylinder 15 and the first surface 16 a of the piston 16, and the inner surface of the cylinder 15 and the first surface 16 a of the piston 16. And a second pressure line 21 connected to the second space 20 formed by the second surface 16b opposite to the first surface 16b. The tip of the rod 17 is covered with a cap 29. Since the cap 29 directly contacts the outer peripheral surface of the semiconductor wafer W when the semiconductor wafer W is clamped, the cap 29 can be replaced. Further, plates 31 and 32 are provided between the tip of the rod 17 and the cylinder 15 in order to avoid direct contact between the tip of the rod 17 and the cylinder 15.

  The piston 16 is provided with a through hole 22 that connects the first space 18 and the second space 20, and a screw 23 that is fitted in the through hole 22. Moreover, the cross-sectional shape of the piston 16 is a convex shape. For this reason, the first surface 16a of the piston 16 is a surface having a convex tip portion, and the second surface 16b is a surface opposite to the surface having the tip portion. A spring 24 is provided at the tip of the piston 16. Therefore, the piston 16 reciprocates in the cylinder 15 using the spring 24 and the pressure difference between the first space 18 and the second space 20.

  The cylinder 15 is provided with a connection hole 25 that connects the first pressure line 19 and the first space 18, and a connection hole 26 that connects the second pressure line 21 and the second space 20. ing. The first pressure line 19 is a line for evacuating the first space 18 to open a vacuum by opening a valve 27 (for example, an electromagnetic valve) provided in the vicinity of the first space 18. The second pressure line 21 is a line through which air flows into the second space 20 by opening a valve 28 (for example, an electromagnetic valve) provided in the second space 20.

  A member that does not easily generate dust when the semiconductor wafer W is clamped or unclamped by the hand 1 is used for the piston 16 or the like constituting the hand 1. For example, Vespel (manufactured by DuPont) is used for the piston 16, rod 17, cap 29, plates 30 and 31, and PEEK (polyetheretherketone) is used for the receiving portion 14. For the cylinder 15, for example, aluminum (Al) is used.

  As shown in FIG. 3, the transfer robot 51 provided with the hand 1 has an actuator 52, an arm 53a connected to the actuator 52, one connected to the arm 53a, and the other connected to the hand 1. Arm 53b. FIG. 3 shows a state where the semiconductor wafer W clamped by the hand 1 is transferred by the transfer robot 51 and stored in the carrier 54.

  Next, a method for manufacturing a semiconductor device according to an embodiment of the present invention will be described along the manufacturing flow shown in FIG. 4 with reference to FIGS. FIG. 4 is a manufacturing flowchart of the semiconductor device according to the present embodiment.

  When the semiconductor wafer W is transferred by the hand 1 in the manufacturing process of the semiconductor device, first, the arm of the transfer robot is moved, and the semiconductor wafer W is mounted on the stage 12 of the hand 1 provided at the tip of the arm. (Step S1).

  Next, the movable part 13 is moved in the direction toward the stage 12, whereby the semiconductor wafer W mounted on the stage 12 is clamped by the movable part 13 and the receiving part 14 (step S2). The movement of the movable portion 13 will be described. The spring 24 is contracted by evacuating the first space 18 from the first pressure line 19 with the second pressure line 21 closed by the valve 28, for example, about 60 kPa. At the same time, the piston 16 and the rod 17 are moved, and the movable portion 13 which is the tip portion of the rod 17 is moved. At this time, the pressure in the first space 18 is actually about 30 kPa by leaking through the through hole 22 and the screw 23.

  For this reason, the pressure of the first space 18 can be controlled to be constant by the screw 23, and the force for clamping the semiconductor wafer W (clamping force) can also be controlled to be constant. Further, it is possible to control the clamping force, prevent the semiconductor wafer W from being broken, and improve the manufacturing yield of the semiconductor device.

  In addition, when the semiconductor wafer W is clamped, even if metal foreign matter or foreign matter due to rubbing between the cylinder 15 and the rod 17 occurs from the rod 17 of the cylinder 15, a vacuum is drawn in the first space 18. Thus, these foreign matters are exhausted from the first pressure line 19 and can be prevented from scattering to the semiconductor wafer W. That is, in the process of transporting the semiconductor wafer W using the hand 1, the generation of foreign matters can be reduced.

  Next, with the semiconductor wafer W clamped, the arm of the transfer robot is moved to transfer the semiconductor wafer W mounted on the hand 1 to a predetermined place such as the carrier 54 (step S3). The semiconductor wafer W can be transferred at a high speed because the semiconductor wafer W is transferred while being clamped.

  Next, at a predetermined location such as the carrier 54, the movable portion 13 moves in the direction opposite to the stage 12 side, thereby unclamping the semiconductor wafer W mounted on the stage 12 (step S4). The movement of the movable portion 13 will be described. When the first pressure line 19 is closed by the valve 27, for example, air of about 400 kPa flows from the second pressure line 21 into the second space 20, whereby the spring 24 extends. At the same time, the piston 16 and the rod 17 are moved, and the movable portion 13 which is the tip portion of the rod 17 is moved.

  For this reason, even if metal foreign matter or foreign matter due to rubbing of the clamp link portion is generated from the rod 17 of the cylinder 15 when the semiconductor wafer W is unclamped, the air in the second space 20 remains in the first space. Therefore, the contaminated air can be prevented from being discharged to the semiconductor wafer W side. That is, in the process of transporting the semiconductor wafer W using the hand 1, the generation of foreign matters can be reduced.

  Further, in the process of clamping the semiconductor wafer W (step S2), the first space 18 is evacuated from the first pressure line 19 with the second pressure line 21 closed, whereby the piston 16 moves and the connection hole is formed. When 25 is closed, it is detected that the semiconductor wafer W is not mounted on the stage 12 (step S5). When a clamping error occurs in the semiconductor wafer W, the piston 16 further moves in the direction toward the stage 12, closes the connection hole 25, and rises to a supply vacuum value of, for example, about 60 kPa.

  For this reason, the clamp of the semiconductor wafer W and the misclamp can be detected by the vacuum differential pressure. Further, since the misclamp can be detected in this way, a wafer clamp detection sensor or the like that is conventionally provided in the transfer robot becomes unnecessary.

  In this way, by transporting the semiconductor wafer W using the hand 1 in the present embodiment, it is possible to construct a clean transport technique by eliminating the generation of foreign matter dust. In addition, it is possible to eliminate the cause of metal contamination due to metal foreign matter. In addition, a device for dust generation treatment is not required, the transport robot can be made compact, and the cost of the equipment can be reduced. Further, since the configuration of the hand 1 is simple, a long life can be realized, and further, maintenance-free can be realized by extending the life.

  Next, a semiconductor device transfer system according to an embodiment of the present invention will be described with reference to FIG. FIG. 5 is an explanatory diagram schematically showing the overall configuration of a transport system using a hand in the present embodiment.

  As shown in FIG. 5, the transfer system 60 described in the present embodiment is constructed in a clean room in a semiconductor manufacturing factory. A track 61 is laid on the ceiling side in the clean room, and the transport carriage 62 travels on the track 61 in response to a command from a transport control device (not shown).

  The transfer carriage 62 is mounted with a transfer container 70 that functions as an inter-device-group mixed transfer container configured as a hoop or the like for storing semiconductor wafers. In the case shown in FIG. 5, the track 61 laid on the ceiling side is formed in a loop shape, and the transport container 70 formed in a hoop or the like circulates while being mounted on the transport carriage 62. Yes.

  On the other hand, in the loop of the track 61, processing devices for performing a series of processes corresponding to various processes on the semiconductor wafer when manufacturing the semiconductor device are divided into a plurality of areas and arranged as device groups 100, 200, 300. Yes. For example, in the case illustrated in FIG. 5, the device group 100 includes devices 100 a, 100 b, 100 c, 200 a, 200 b, 200 c, 300 a, 300 b, and 300 c.

  In the apparatus group 100, the conveyance path 63 is laid on the floor so as to connect the apparatuses 100a, 100b, and 100c, and the conveyance carriage 64 travels on the conveyance path 63. The transfer carriage 64 is equipped with a transfer container 70 that functions as a transfer container in the apparatus group configured as a hoop for storing semiconductor wafers. Inter-device transfer in the device group 100 is performed in a state where the semiconductor wafer is housed in a hoop.

  The configuration of the device group 100 is similarly configured in the other device groups 200 and 300, and conveyance between the devices 200a, 200b, and 200c and between the devices 300a, 300b, and 300c is performed on a conveyance path 63 laid on the floor. This is done by running a transport cart 64 equipped with a hoop.

  Further, as shown in FIG. 5, stations 100 </ b> S, 200 </ b> S, and 300 </ b> S are provided on the track 61 so as to correspond to the respective device groups 100, 200, and 300. Each station 100S, 200S, 300S is provided with a wafer transfer means 80 configured as a wafer sorter. In addition, storage means 90 configured in the stocker is also provided.

  The transfer robot 51 having the hand 1 described above can be applied to, for example, a wafer sorter. For this reason, generation | occurrence | production of a foreign material can be reduced in the process of conveying the semiconductor wafer using the hand 1. FIG.

  In these stations 100S, 200S, and 300S, a transport carriage 62 that travels on the track 61 and a transport carriage 64 that is responsible for transport in the device groups 100, 200, and 300 are stopped as necessary.

  For example, it is assumed that the semiconductor wafer W1 that has been processed by the apparatus 100a of the apparatus group 100 corresponding to a certain process needs to be transferred to the apparatus 300b constituting the apparatus group 300 corresponding to the next process and processed. On the other hand, it is assumed that the processing of the semiconductor wafer W2 of a different lot is completed in the apparatus 200b of the apparatus group 200 corresponding to another process, and the apparatus 300b constituting the apparatus group 300 corresponding to the next process needs to be processed.

  As shown in FIG. 5, when the processing of the semiconductor wafer W1 is completed in the apparatus 100a of the apparatus group 100, as indicated by the arrow a in the figure, the semiconductor wafer is placed in the hoop mounted on the transfer carriage 64 that is responsible for the transfer within the apparatus group. W1 is stored. Such transfer is automatically performed for each sheet by a robot.

  The hoop containing the semiconductor wafer W1 is mounted on the transfer carriage 64, travels on the transfer path 63 to the station 100S, and arrives at the station. Along with the arrival of the station 100S of the transport cart 64, the transport cart 62 (indicated by the arrow b in the figure) traveling on the track 61 also arrives at the station 100S.

  When the transport carts 62 and 64 arrive at the station 100S, the doors of the hoops mounted on the transport carts 62 and 64 are automatically opened. The wafer sorter pulls out the semiconductor wafer W1 that has been processed in the apparatus 100a from the hoop on the transfer carriage 64 and transfers it to the hoop on the transfer carriage 62. Such a state is indicated by an arrow c in the figure.

  In this way, the hoop after the transfer of the semiconductor wafer W1 is mounted on the transfer carriage 62, toward the station 200S provided corresponding to the apparatus group 200 as indicated by the arrow d in the figure. And run.

  On the other hand, in the apparatus group 200, the semiconductor wafer W2 for which required processing has been completed in the apparatus 200b is moved into a hoop mounted on the transport carriage 64 as indicated by an arrow e in the figure, as in the apparatus 100a. It is. The semiconductor wafer W2 is transferred to the station 200S while being stored in the hoop.

  At the station 200S, the transfer carriage 62 on which the hoop containing the semiconductor wafer W1 is mounted arrives at the station so as to coincide with the arrival station of the transfer carriage 64. In this way, the doors of the hoops mounted on the respective transport carriages 62 and 64 are automatically opened in a state where both the transport carriages 62 and 64 have arrived at the station 200S, and the wafer sorter moves from the hoop to the inside of the hoop. The semiconductor wafer W2 is transferred to the empty space. The semiconductor wafers W1 and W2 of different lots are mixedly loaded in the same hoop. Such a state is indicated by an arrow f in the figure.

  In this way, the FOUP in which the semiconductor wafers W1 and W2 that are handled differently are mounted is mounted on the transfer carriage 62, and the station 300S provided corresponding to the apparatus group 300 is instructed by the arrow g in the figure. Head for.

  At the station 300S, the transfer carriage 64 responsible for transfer in the apparatus group 300 arrives at the arrival station of the transfer carriage 62, and the semiconductor wafers W1 and W2 are pulled out from the hoop mounted on the transfer carriage 62 by the wafer sorter. Then, it is transferred into a hoop mounted on the transport carriage 62. The hoop is emptied. Such a state is indicated by an arrow h in the figure.

  The semiconductor wafers W1 and W2 transferred in this way are transferred to the apparatus 300b as indicated by the arrow i in the figure while being accommodated in the FOUP, and a required process is performed by the transfer destination apparatus 300b. Applied. On the other hand, the hoop emptied at the station 300S circulates on the track 61 while being mounted on the transport carriage 62 as indicated by the arrow j in the figure.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  For example, in the above-described embodiment, the case where the present invention is applied to a wafer sorter of a transfer system has been described.

  The present invention is widely used in the manufacturing industry for manufacturing semiconductor devices.

It is a top view which shows typically the hand in embodiment of this invention. It is sectional drawing of the A-A 'line | wire of FIG. It is a top view which shows typically the robot for conveyance which has a hand in this Embodiment. 6 is a manufacturing flowchart of the semiconductor device according to the present embodiment. It is explanatory drawing which shows typically the whole structure of the conveyance system using the hand in this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hand 12 Stage 13 Movable part 14 Receiving part 15 Cylinder 16 Piston 16a 1st surface 16b 2nd surface 17 Rod 18 1st space 19 1st pressure line 20 2nd space 21 2nd pressure line 22 Through-hole 23 Screw 24 Spring 25 26, connection holes 27, 28 Valve 29 Cap 31, 32 Plate 51 Transfer robot 52 Actuator 53a, 53b Arm 54 Carrier 60 Transfer system 61 Track 62 Transfer carriage 63 Transfer path 64 Transfer carriage 70 Transfer container 80 Wafer transfer means 90 Storage Means 100 Device group 100a, 100b, 100c Device 100S Station 200 Device group 200a, 200b, 200c Device 200S Station 300 Device group 300a, 300b, 300c Device 300S Station W, W1, W2 Semiconductor wafer

Claims (3)

A stage on which a semiconductor wafer is mounted;
A movable part and a receiving part provided at an edge of the stage;
Use a hand with
(A) a step of clamping the semiconductor wafer mounted on the stage with the movable portion and the receiving portion by moving the movable portion in the direction toward the stage;
(B) unclamping the semiconductor wafer mounted on the stage by moving the movable part in a direction opposite to the stage side;
A method of manufacturing a semiconductor device having
The movable portion is a tip portion of a rod extending from the first surface side of the piston that reciprocates in the cylinder,
The rod is fixed to the piston;
The cylinder includes a first pressure line connected to a first space formed by an inner surface of the cylinder and the first surface of the piston, an inner surface of the cylinder and the first surface of the piston. A second pressure line connected to the second space formed by the opposite second surface, and
The piston is provided with a through hole connecting the first space and the second space, and a screw fitted in the through hole,
In the step (a), by evacuating the first space from the first pressure line with the second pressure line closed, the piston moves and the movable part moves,
In the step (b), when the first pressure line is closed, air flows into the second space from the second pressure line, so that the piston moves and the movable part moves. A method for manufacturing a semiconductor device.   2. The method of manufacturing a semiconductor device according to claim 1, wherein in the step (a), the vacuum in the first space leaks by the screw, and the pressure in the first space is made constant. The cylinder is provided with a connection hole for connecting the first pressure line and the first space,
Furthermore,
(C) When the first space is evacuated from the first pressure line with the second pressure line closed, when the piston moves and closes the connection hole, the semiconductor is placed on the stage. A process for detecting that no wafer is mounted;
The method of manufacturing a semiconductor device according to claim 1, wherein:

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