JPH0249717Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application The present invention relates to a semiconductor wafer transfer device, and more specifically, to a device that is used in the manufacture of semiconductor devices and transfers multiple semiconductor wafers at once between a carrier and a boat. be.

2. Description of the Related Art Semiconductor devices are manufactured using semiconductor wafers (hereinafter simply referred to as wafers) on which a large number of semiconductor elements are formed.
This is done by processing in various processing steps. Among these various processing steps, for example, CVD
In the oxide film treatment process using the method, only one side of the wafer is treated, so as shown in Fig. 20, a plurality of wafers 1, 1, . A back-to-back method is adopted in which the wafers are aligned and held at a fixed pitch slightly tilted on a wafer-specific holding jig (a boat described later). Two wafer-dedicated holding jigs are used in this back-to-back oxide film treatment step and its preceding and following steps. That is, a frame-shaped Teflon carrier as shown in FIG. 21 is used to store a plurality of wafers 1, 1, . . . one by one in the wafer storage grooves 2, 2, . 3, and a plurality of wafers 1, 1..., two by two, are planted with their back surfaces in close contact with each other, and are slightly tilted into the wafer holding grooves 4, 4... to hold them aligned at a constant pitch. The wafer 1,
It is necessary to transfer 1... all at once.

Back to Back between the above carrier 3 and boat 5
To transfer wafers using this method, as shown in FIG. The wafers 1, 1, . . . transferred from the boat 5 are brought into close contact or separated by changing their alignment, and then loaded or unloaded onto an empty boat 5 or carrier 3. When loading or unloading the wafers 1, 1..., a pusher 11 is disposed under the carrier base 6 and the boat base 7 so as to be movable up and down, and has wafer receiving grooves 9...10... cut into its upper surface. , 12 between the carrier 3 or boat 5 and the holder 8.
... to be transferred. In particular, as shown in FIG. 24, the wafers 1, 1, . . . on the boat 5 are held in a slightly tilted state with respect to the boat 5.
In order to align the rising direction of the wafers 1, 1... with the lifting direction of the pusher 12, the boat base 7 is arranged to be inclined in the opposite direction to the wafer tilting direction, and the wafers 1, 1 on the boat 5 are arranged with respect to the pusher 12. 1
... to be held vertically. As a result, during wafer loading or unloading, the wafers 1 and 1 on the boat 5 are moved up and down by the pusher 12.
1. It facilitates the delivery of...

Problems to be solved by the invention By the way, since the boat 5 used in the above-mentioned processing process is made of quartz glass, the wafers 1,
The boat 5 is etched by the chemical liquid during the chemical liquid treatment performed after the process 1..., and as a result, the width of the wafer holding grooves 4, 4... increases.

In this way, the wafer holding grooves 4, 4... of the boat 5...
As the width of the groove becomes larger, first, during wafer loading, when transferring two wafers 1, 1... with their back sides in close contact with each other from the holder 8 onto the empty boat 5, the pusher The wafers 1, 1... held vertically by the 12 wafer receiving grooves 10, 10... are fitted into the wafer holding grooves 4, 4... of the boat 5 due to the downward movement of the pusher 12, and at the same time are tilted significantly. As a result, the lower edge of the wafers 1, 1... is stuck in the wafer holding grooves 4, 4...
There was a problem in that the wafers 1, 1, etc. were scratched due to friction within the wafers, and foreign matter was generated.

Also, during wafer unloading, when transferring the wafers 1, 1... from the boat 5 to the holder 8, the wafers 1, 1... held planted in the wafer holding grooves 4, 4... of the boat 5 are pushed. 1
2, the wafer receiving grooves 10, 10
Even if an attempt was made to hold the wafers vertically in the wafer holding grooves 4, 4..., the wafers 1, 1... were tilted significantly in the wafer holding grooves 4, 4..., so it was difficult to transfer the wafers from the boat 5 to the pusher 12. .

Therefore, an object of the present invention is to provide a semiconductor wafer stand-up device that allows loading and unloading of wafers after correcting the posture of the wafers on the boat even if the state of holding the wafers on the boat changes over time. .

Means for Solving the Problems The present invention was proposed in view of the above problems, and consists of a carrier that stores a plurality of wafers one by one at a fixed pitch, positions and places them on a carrier base, and the wafers. A device that holds two wafers aligned at a fixed pitch with their back sides in close contact with each other, and changes the alignment state of the wafers and transfers the wafers between the boat and the boat, which are positioned and placed on a boat base. are arranged at a fixed pitch on the side of the boat so that they can move in parallel along the wafer alignment direction, and can protrude and retract between each wafer in a direction perpendicular to the wafer alignment direction, and support the lower part of each wafer. a plurality of pins that are tilted or erected; a first sensor that is disposed between any two pins so as to be able to move in parallel following the pins, and that detects the presence or absence of a wafer by the parallel movement; The wafer is fixedly placed in a standing position on the boat.
A second sensor detects the presence or absence of a wafer by the wafer raising operation by the pin, and third and fourth sensors are fixedly arranged at predetermined positions along the wafer alignment direction on the side of the boat and detect the origin position and protrusion/retraction position of the pin.
This is a semiconductor wafer reloading device that achieves the above object by being equipped with a sensor.

Effect: According to the present invention, when loading wafers onto a boat, the pins are moved in parallel to their protrusion/retraction positions and protruded based on the detection signals from the third and fourth sensors, and the wafers loaded onto the boat are is held by the boat and supported by leaning on the pin. In this state, if the pin is moved in parallel and stopped based on the detection signal of the first sensor, and then moved back and forth to return to the original position, the loaded wafer will be
It is held on the boat while being guided by the parallel movement of the pin. Also, when unloading a wafer from a boat, the pin is moved in parallel to the protrusion/retraction position based on the detection signal of the first sensor, and the pin is protruded from the second sensor.
Based on the detection signal of the sensor, the pins are moved in parallel while supporting the wafers on the boat until the wafers on the boat are in an upright state, and then the wafers in an upright state on the boat are unloaded. In this manner, wafers can be loaded and unloaded after correcting their posture during wafer loading and unloading, and are not affected by changes in the boat over time.

Embodiment An embodiment of the semiconductor wafer reloading apparatus according to the present invention will be described with reference to FIGS. 1 to 19. In addition, FIGS. 1 to 3 show the structure of the boat part of the semiconductor wafer transfer apparatus, FIGS. 4 to 7 show the overall structure of the semiconductor wafer transfer apparatus, and FIGS. 8 to 19 show the structure of the boat part of the semiconductor wafer transfer apparatus. The operating status during harrowing and unloading is shown.

The semiconductor wafer reloading device 15 shown in FIGS. 4 to 7 stores a plurality of wafers 1, 1, . A carrier part 17 having a horizontally movable carrier base 16 on which a frame-shaped Teflon carrier 3 (see FIG. 21) is positioned and placed, and a plurality of wafers 1, 1, two by two, with their back surfaces facing each other. A horizontal movable boat on which a table-shaped quartz glass boat 5 (see Fig. 22) is positioned and placed, which is slightly tilted in the wafer holding grooves 4, 4, and held in alignment at a fixed pitch while the wafers are closely planted. It has a freely movable boat base 18, has a boat part 19 arranged in parallel with the carrier part 17, and is arranged above an intermediate position _P0 between the carrier part 17 and the boat part 19, and can be transferred from the carrier 3 or the boat 5. The wafers 1, 1... are temporarily stored and held, and the wafers 1, 1... are brought into close contact with each other or separated using two pairs of vertically rotating rollers 20 to 24 to change their alignment state. The main part thereof is composed of a holder part 25 having a holder 24 and a holder part 25. Incidentally, each of the above-mentioned carrier section 17, boat section 19, and holder section 25 is driven and controlled by a control section (not shown) as described later.

Directly below the carrier section 17 and boat section 19 are base transfer mechanisms 26 and 27 that transfer the carrier base 16 and boat base 18 between standby positions P ₁ and P ₂ and intermediate position P ₀ , respectively. will be established. Further, at the lower part of the carrier base 16 and the boat base 18, the wafers 1 and 1 are placed between the carrier 3 and the boat 5 and the holder 24.
A vertically movable pusher 28, 2 for transferring ...
Pusher mechanisms 30 and 31 having 9 are integrally installed. Wafer receiving grooves for holding the wafers 1, 1, . As shown in FIG. 7, the boat base 18 holds the wafers 1, 1... on the boat 5 in alignment by tilting them at a minute angle. The wafers 1, 1...
The rising direction of the pusher 29 and the rising and falling direction of the pusher 29 are aligned. Further, the holder portion 25 is provided with a holder elevating mechanism 32 for moving the holder 24 up and down.

The feature of the present invention lies in the boat base 18 of the boat section 19. The specific structure of the boat base 18 will be described below.

In the boat base 18 shown in FIGS. 1 to 3, reference numeral 33 denotes a substantially rectangular base plate on which the boat 5 described above is positioned and mounted, and at the substantially central portion thereof, there is a vertically movable portion (not shown) below. An open window hole 34 is provided through which a pusher 29 (see FIG. 6) is inserted. 35, 35... are movable in parallel along the wafer alignment direction on the side of the boat 5,
In addition, the wafers 1, 1... are arranged at fixed pitches so as to be protrusive and retractable between each wafer 1, 1... along a direction perpendicular to the wafer alignment direction, and are tilted or erected by supporting the lower part of each wafer 1, 1... Multiple pins.
The tip portion that comes into contact with the wafers 1, 1, . . . is made of Teflon. 36 is the above pin 35, 35...
The pin base is planted facing the boat 5 along the wafer alignment direction, and 37 is the two guide rods 3.
The main base has 8 and 38 slidably inserted through it,
A pin base 36 is bridged and fixed to the inner shaft ends of the guide rods 38, 38, and a connecting bar 39 is bridged and fixed to the outer shaft ends. 40
A cylinder is a driving source for protruding and retracting the pins 35, 35, . Fix it. Reference numerals 41 and 42 denote front and rear support frames erected at the front and rear ends of the base plate 33, and guide rods 4 protruding from the front and rear end surfaces of the main base 37.
3, 43, 44, and 44 are slidably inserted therethrough.
A motor 45 is a driving source for moving the main base 37 in parallel along the wafer alignment direction, and is fixed below the base plate 33. 46 is a cylindrical cam fixed coaxially to the output shaft of the motor 45; 47
A block 48 is fixed to the outer surface of the main base 37, and a cam follower is rotatably supported at the lower end of the block 48. The cam follower 47 is connected to the cylindrical cam 4 by
6 in constant contact. 50 is the main base 3 above
7 and the two pins 3 of the pin base 36
A first sensor consisting of a fiber photoelectric switch disposed toward the boat 5 side between 5 and 35; 51 is a sensor mounting arm 5 extending from the front support frame 41;
A second sensor consisting of a fiber photoelectric switch is fixed to the tip of the boat 5 and is fixedly arranged on the side of the boat 5 toward the boat 5, and is located at a position corresponding to the wafer holding grooves 4, 4, . . . of the boat 5, that is, It is placed on an extension of the wafer standing position. Reference numerals 53 and 54 denote third and fourth sensors, which are photo sensors fixedly arranged at the rear end of the base plate 33 and near the rear support frame 42, and project outward from the rear end of the main base 37. The origin position and protruding/retracting position of the pins 35, 35, . Note that 55 and 56 are fifth and sixth sensors fixed to the front end of the main base 37, and the light shielding plate 57 at the front end of the pin base 36
By detecting the presence or absence of pins 35, 35...
This is to confirm the protrusion or retraction state of the

Semiconductor wafer advance equipment 15 having the above configuration
The transfer operation during wafer loading and unloading will be described below.

First, during wafer loading, the carrier 3 stores multiple wafers 1, 1... one by one.
is positioned and placed on the carrier base 16 of the carrier section 17. Then, the carrier base 16 is transferred to an intermediate position P ₀ by the base transfer mechanism 26, and at this position P ₀ the pusher mechanism 3
0, it is transferred to the holder 24 of the holder section 25. Next, a plurality of wafers 1, 1, . . _. facing in the opposite direction to the wafers 1, 1, . The carrier 3 is shifted by half a pitch, and the wafers 1, 1, . This holder 24 uses vertically rotating rollers 20 to 24 to change the alignment of the wafers 1, 1, . . . by bringing their back surfaces into close contact with each other. Then, the wafers 1, ₁ , .

At this time, the wafer loading operation at the boat base 18 is as follows.

First, the cylindrical cam 46 is rotated by driving the motor 45, and the cam follower 47 is attached to the cylindrical cam 46.
The main base 37 is moved parallel to the side of the empty boat 5 along the wafer alignment direction. As a result, pins 35, 35 at the origin position
...is translated in parallel along the wafer alignment direction,
Based on the detection signal of the fourth sensor 54, it is stopped at the protruding and retracting position. [See Figures 8 and 9]
This position is the wafer holding groove 4, 4... of the boat 5.
... is a position near the top. Based on the detection signal of the fourth sensor 54, the pins 35, 35, . Place it in between. Thereafter, the pusher 29 of the pusher mechanism 31 below the boat base 18 is lowered from the holder 24, and the wafers 1, 1, etc., which are in close contact and are planted in the wafer receiving groove on the pusher 29, are transferred to the wafer holding groove of the boat 5. Transfer to 4, 4... At this time,
The wafers 1, 1, . . . fitted into the wafer holding grooves 4, 4, . . . are supported by pins 35, 35, . From this state, slowly move the pins 35, 35... in parallel in the direction opposite to the wafer support side,
The wafers 1, 1, . . . are supported by pins 35, 35, . . . and tilted, the presence or absence of the wafers 1, 1, . Since the first sensor 50 is disposed between any two pins 35, 35, at this time, the wafers 1, 1... are supported by the wafer holding grooves 4, 4... of the boat 5. [See Figures 12 and 13]. The wafer holding grooves 4, 4, .
are aligned with the groove wall surfaces of the wafer holding grooves 4, 4, . . . in the inclined direction. Then, the pins 35, 35... are stopped based on the detection signal of the first sensor 50, and the pins 35, 35 are stopped by the protruding operation of the cylinder 40.
5... are moved back and forth, and further moved in parallel via the main base 37, and then returned to the original position based on the detection signal of the fourth sensor 53 and stopped.

In this way, when loading the wafer,
Even if the width of the wafer holding grooves 4, 4... increases due to changes in the boat 5 over time, the pins 3
The wafers 1, 1, . Since there is no sudden collapse of the wafers 1, 1, . . ., there is no fear that the wafers 1, 1, .

Next, at the time of wafer unloading, a boat 5 holding a plurality of wafers 1, 1 . Then, the boat base 18 is transferred to the intermediate position P ₀ by the base transfer mechanism 27, and this position is
At _P0 , the pusher mechanism 31 transfers it to the holder 24 of the holder section 25.

At this time, the wafer unloading operation at the boat base 18 is as follows.

First, by driving the motor 45, the main base 37 is moved in parallel along the wafer alignment direction of the boat 5 on its side via the cylindrical cam 46 and the cam follower 47. As a result, the pins 35, 35... located at the origin position are moved in parallel along the wafer alignment direction, the first sensor 50 detects the presence or absence of the wafers 1, 1... on the boat 5, and the detection signal is [See Figures 14 and 15]. At this time, since the first sensor 50 is located approximately in the middle of the two pins 35, 35, each pin 35, 35... is placed laterally between each wafer 1, 1... on the boat 5. Ru. Based on the detection signal of the first sensor 50, the pins 35, 35, . (See Figures 16 and 17). Thereafter, the pins 35, 35... are moved in parallel along the wafer alignment direction to stand up while supporting the wafers 1, 1..., and the second sensor 51 detects the wafers 1, 1...
The presence or absence of the motor is detected and the system is stopped based on the detection signal (see FIGS. 18 and 19). This second sensor 51 is connected to the wafer holding grooves 4, 4... of the boat 5.
At this time, the wafers 1, 1, . . . are held upright within the wafer holding grooves 4, 4, . The direction is aligned. From this state, the pusher 29 of the pusher mechanism 31 below the boat base 18 is raised, and the wafers 1, 1, . . . , which are held upright by the pins 35, 35, . Then, it is transferred to the holder 24. After that, the pin 35,
35... are moved back and forth, and further moved in parallel via the main base 37, and then returned to the original position based on the detection signal of the fourth sensor 53 and stopped. In the holder 24, the wafers 1, 1, .

In this way, even if the width of the wafer holding grooves 4, 4... increases due to changes in the boat 5 over time during wafer unloading, and the wafers 1, 1,... 35,
The wafers 1, 1, . I can do it.

Effects of the invention According to the invention, wafer loading and unloading can be carried out reliably and quickly on the boat without damaging the wafers, without being affected by changes in the boat over time, and has great practical value. It is possible to provide a semiconductor wafer stand-alone equipment with improved workability and product yield.

[Brief explanation of the drawing]

1 to 19 are for explaining an embodiment of the semiconductor wafer reloading apparatus according to the present invention, in which FIG. 1 is a plan view showing a boat base, FIG. 2 is a front view thereof, and FIG. 3 is a plan view showing a boat base. 4 is a plan view showing the overall configuration of the semiconductor wafer reloading device, FIG. 5 is a front view of the entire device, FIG. 6 is a right side view of the entire device, and FIG. 8 and 9, 10 and 11, 12 and 13 are side views showing the boat part of the device, and FIGS. 12 and 13 are side views and partial side views showing the wafer loading state on the boat base. Plan view, Figures 14 and 15, 1st
6, FIG. 17, FIG. 18, and FIG. 19 are a partial side view and a partial plan view showing the wafer unloading state on the boat base. Fig. 20 is a side view showing wafers on a boat using the back-to-back method; Fig. 21 is a perspective view showing a carrier with wafers arranged and stored; Fig. 22 is a perspective view showing a boat holding wafers in alignment; FIG. 23 is a schematic configuration diagram of a conventional semiconductor wafer reloading apparatus, and FIG. 24 is a side view showing a boat base and pusher. 1... Semiconductor wafer, 3... Carrier, 5...
... Boat, 16 ... Carrier base, 18 ... Boat base, 35 ... Pin, 50 ... First sensor, 51 ... Second sensor, 53, 54 ... Third,
Fourth sensor.

Claims (1)

[Scope of Claim for Utility Model Registration] A carrier in which a plurality of semiconductor wafers are arranged and stored one by one at a fixed pitch, and positioned and placed on a carrier base, and two semiconductor wafers are placed in close contact with each other with their back surfaces at a fixed pitch. A device for transferring semiconductor wafers to and from a boat that is aligned and placed on a boat base while changing the alignment state of the semiconductor wafers. a plurality of pins that are movable in parallel and are disposed at fixed pitches between each semiconductor wafer so as to be able to protrude and retract along a direction perpendicular to the wafer alignment direction, and that support the lower part of each semiconductor wafer and tilt or erect it; A first sensor is disposed between any two pins so that it can move in parallel following this pin, and detects the presence or absence of a semiconductor wafer by the parallel movement, and a first sensor is fixed to the wafer's upright position on the boat at the side of the boat. a second sensor that is arranged and detects the presence or absence of a semiconductor wafer by a wafer raising operation using a pin;
A semiconductor wafer stand-up device comprising third and fourth sensors that are fixedly arranged at predetermined positions along the wafer alignment direction on the side of the boat and detect the origin position and protrusion/retraction position of the pins.