JPH03181145A - Boat ditch detection method and device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and device for detecting grooves in a boat used in a wafer transfer device in a semiconductor manufacturing device such as a vertical diffusion/CVD device.

[Conventional technology and its issues]

Conventionally, when taking out the wafer in a cassette with a tweezer and transferring it to a quartz boat, in order to accurately insert it into the groove on the boat, it was necessary to actually use a wafer or an original product to perform the transfer operation. It is necessary to find the optimal position by human visual inspection, and this operation is necessary every time the quartz boat is reinstalled due to cleaning or replacement, so the operator visually aligns the wafer and boat groove positions. Not only is this time-consuming, but if the position is incorrectly taught, the wafers and the boat may come into contact and collide, leading to damage to the wafers or the boat, and the transfer cannot function properly.

[Means to solve the problem]

In order to solve the above problems, the method of the present invention raises or lowers the boat 3 by means of a boat lifting mechanism 16 during the wafer transfer operation, as shown in the first diagram, and detects the raising or lowering of the boat 3 by means of a groove detection sensor 14. The groove position and groove width of the boat 3 are detected by the boat groove detection unit 6 based on the groove detection signal output from the groove detection sensor 14 and the boat position signal output from the boat position detector 5 of the boat lifting mechanism 16. In order to solve the same problem, the device of the present invention has a boat lifting mechanism 16 that lifts and lowers the boat 3 as shown in the first diagram, and a boat lifting mechanism 16 that monitors the lifting and lowering of the boat 3 and outputs a groove detection signal. A groove detection sensor 14 and a boat position detector 5 that outputs a boat position signal.
and a boat groove detection section 6 which inputs the output of the groove detection sensor 14 and the output of the boat position detector 5 to detect the groove position and groove width of the boat 3.

[For production]

The boat 3 is raised or lowered by the boat lifting mechanism 16, and this raising or lowering of the boat 3 is detected by the groove detection sensor 1.
4, and a groove detection signal is output from this groove detection sensor 14. On the other hand, when the boat 3 is raised or lowered, its position is detected by the boat position detector 5, and this position detection signal and groove detection signal are input to the boat groove detection section 6, and the groove position and groove width of the boat 3 are detected. Ru.

〔Example〕

The present invention will be described in detail below based on the drawings.

FIG. 1 is an explanatory diagram showing a horizontal diaphragm in one embodiment of the method and apparatus of the present invention, FIG. 2 is an explanatory diagram showing an example of a groove detection sensor in the present invention, and FIGS. 3(a) and (b) are FIG. 3 is an explanatory diagram of groove detection by the sensor of FIG. 2;

In FIG. 1, reference numeral 16 denotes a boat lifting mechanism for lifting and lowering a quartz boat 3 having grooves 3a for holding a large number of wafers. It is a horizontal choke that allows the quartz boat 3 placed on the moving table 18 to be raised or lowered.

Reference numeral 14 denotes a groove detection transmission type laser light sensor that monitors the elevation of the boat 3 and outputs a groove detection signal.
The light emitting unit 1 and the light receiving unit 2 that horizontally diaphragm the boat lift mechanism 16
are attached to fixed portions around the boat 3 facing each other via a groove 3a. The laser light sensor 14 is shown in FIG.
As shown in FIGS. 3(a) and 3(b), the laser beam 15 output from the semiconductor laser light emitting element 10 of the light projecting part 1 is received by the light receiving element 12 of the opposing light receiving part 2 and converted into an electrical signal. It is. Light reception! 2 is designed to narrow down the detection area with a pickpocket 7) 11 to improve detection accuracy, and the projecting and receiving part 1.2 is located at a position where it can cover the entire area of the boat 3 as the boat 3 moves up and down.

A rotary encoder 5 detects the position of the boat 3 as the boat 3 moves up and down, and outputs a boat position signal. Reference numeral 6 denotes a boat groove detection section that receives the output of the laser light sensor 14 and the output of the rotary encoder 5 to detect the groove position and groove width of the boat 3.

7 is a motor controller that controls the elevation of the boat; 8 is a motor driver that inputs a drive signal output from the motor controller 7 to drive the motor 4; 9 is an operation 913;
This is the main control unit operated by. The main control section 9 inputs an output command to the motor controller 7 to drive the motor 4 in groove detection strokes via the motor driver 8, while giving timing for starting detection to the boat groove detection B6. Further, the output of the motor controller 3 is input to the boat groove detection section 6 to improve the detection accuracy.

In this embodiment configured as described above, the main control section 9 is operated by the operating section 13, a command outputted from this is inputted to the motor controller 7, a drive signal outputted from this is inputted to the motor driver 8, and the command outputted from this is inputted to the motor controller 7. by motor 4
is driven. The screw shaft 17 is rotated by the drive of the motor 4, and the movable table 18 and the boat 3 placed thereon are raised or lowered depending on the direction of rotation, and the position of the boat 3 is changed by raising or lowering the boat 3. It is detected by a rotary encoder, and on the other hand, the timing for starting detection is given to the boat groove detection section 6 by the main control section 9.

The laser beam 15 emitted from the semiconductor laser light emitting element 10 of the light projector 91 is intercepted by the non-groove portion of the boat 3, passes through the groove 3aR, passes through the slot 1) 11, is received by the light receiving element 12 of the light receiving section 2, and is emitted by the light receiving element. A groove detection signal is obtained from 12. This groove detection signal and boat position signal are input to the boat groove detection section 6, and the groove position and groove width of the boat 3 are detected. These groove position and groove width signals are input to the main control section 9 and are used as data for the transfer operation.

In the present invention, the position of the groove 3a of the boat 3 is automatically determined by a groove detection sensor 14 attached to a fixed part around the boat lifting mechanism 16, instead of an operator inputting the positional relationship between the wafer and the boat 3 during the wafer transfer operation. By detecting this and correcting the positional relationship with the wafer, it is possible to transfer the wafer to a boat with a different groove position without any trouble.

〔Effect of the invention〕

As described above, according to the present invention, the position of the groove 3a of the boat 3 can be automatically detected by the groove detection sensor 14, so there is no need for the operator to align the wafer by looking at the position of the boat groove. work (number of steps)
In addition, it is possible to prevent malfunctions due to mistakes such as contact and collision between the wafers and the boat 3 and damage to the wafers or the boat 3, and it is possible to perform the correct transfer function. In addition, the boat groove detection unit 6 detects the position and groove width of the boat 3.
Since it can be automatically detected, it can be applied as is to boats with different groove positions, and it is possible to know whether a boat can be used or not by comparing it with a predetermined groove width.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the configuration of one embodiment of the method and apparatus of the present invention, FIG. 2 is an explanatory diagram showing an example of the groove detection sensor in the present invention, and FIGS. FIG. 3 is an explanatory diagram of groove detection by the sensor in FIG. 2; 3... (quartz) boat, 3a... groove,
4... Drive unit (motor), 5... Boat position detector (rotary encoder), 6...
Boat groove detection unit, 7... Drive unit (motor) controller, 8... Drive unit (motor) driver,
9...Main control section, 14...Groove detection (
Transmission type laser beam) sensor, 16... Boat lifting mechanism. ) 2nd eye 3rd eye (b)

Claims (1)

[Scope of Claims] [1] Boat lifting mechanism (16
) to raise or lower the boat (3), the raising or lowering of the boat (3) is monitored by the groove detection sensor (14), and the groove detection signal output from the groove detection sensor (14) and the boat The boat (
3) A boat groove detection method characterized in that the groove position and groove width are detected by a boat groove detection section (6). [2] The output of the boat groove detection section (6) and the output of the drive section controller (7) are input to the main control section (9), and the boat lifting mechanism (16) is controlled by the drive section controller (7) which takes the output as input. 2. The boat groove detection method according to claim 1, further comprising driving the drive unit (4) of the groove detection stroke for each groove detection stroke. [3] Boat lifting mechanism (16) that lifts and lowers the boat (3)
), a groove detection sensor (14) that monitors the elevation of the boat (3) and outputs a groove detection signal, a boat position detector (5) that outputs a boat position signal, and a groove detection sensor (14).
A boat groove detection section (6) detects the groove position and groove width of the boat (3) by inputting the output of the boat (3) and the output of the boat position detector (5).
) and a boat groove detection device. [4] Drive unit (4) of boat lifting mechanism (16) and output and drive unit controller (7) of boat groove detection unit (6)
A main control section (9) which receives the output of
4. The groove detection device for a boat according to claim 3, further comprising a drive unit controller (7) which inputs the output of the unit (9) and drives the drive unit (4) in groove detection strokes.