JPH03181124A - Method and device for boat position detection - Google Patents

Abstract

PURPOSE:To judge it to be in normal condition when a reflection type displacement sensor has not detected displacement in the specified position with a boat and to judge it in abnormal condition when it has detected the displacement and to issue an alarm and also stop the boat to do recovery transaction. CONSTITUTION:A motor 20 operates through a driving part driver 17 by the operation instructive signal of a main controller 18, and a boat elevator 4a and the boat 3 placed on this go up and down. In case that a reflection type displacement sensor 15 does not detect the displacement in the specified distance with the boat 3, the main controller 18 judges that the boat 3 is in normal condition, while in case that it detects the displacement, the main controller judges that there is abnormality such as inclination, breakdown, deformation, etc., in the direction of the boat. When the controller 18 judges that there is abnormality, it issues an alarm and also it stops the driver 17, whereby the operator can perform the recovery transaction from the abnormal condition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a boat position detection method and device used in a boat elevator device in a semiconductor device such as a vertical diffusion/CVD device.

[Conventional technology and its issues]

Conventionally, in order to take a boat into or out of a reaction chamber on a boat elevator, it was necessary to install the boat vertically and keep it in a certain direction, and the operator had to visually confirm that this was the case. Not only do operators make different judgments, which can lead to errors, and operators cannot make judgments if they cannot see the operation of the boat elevator.In addition, when an operator discovers an abnormality, they must stop the abnormal operation and check for abnormalities. There is also the issue of the need to take steps to recover from the condition.

[Means to solve the problem]

In order to solve the above-mentioned problems, the method of the present invention attaches a reflective displacement sensor 15 for boat monitoring, whose distance from the boat 3 is determined, to the boat elevator main body 4 as shown in the figure. If no displacement is detected with respect to a predetermined distance from the boat 3, it is determined that the state of the boat 3 is normal; if a displacement is detected, the direction, inclination of the boat 3,
It is determined that there is an abnormality such as damage or deformation, and if it is determined that there is an abnormality, a warning of the occurrence of the abnormality is issued to the operator, the raising and lowering operations of the boat elevator 4a are stopped, and processing in the event of an abnormality is carried out. It is characterized by

In order to solve the same problem, the device of the present invention includes a reflective displacement sensor 15 for boat monitoring, which is attached to the boat elevator main body 4 and has a determined distance from the boat 3 as shown in the figure.
A reflective displacement sensor I5 is connected to the boat 3 and has a function of inputting an operation instruction signal and outputting an operation instruction signal to a drive section driver 17 that operates a drive section that raises and lowers the boat elevator 4a, and a drive section driver I7. If no displacement is detected within a predetermined distance of If it is determined that there is an abnormality, the main controller 18 issues a warning of the occurrence of an abnormality to the operator and stops the drive section driver 17.

[For production]

An operation instruction signal output from the main controller 18 is input to the drive unit driver 17 to operate the drive unit 20, and this drive 120 causes the boat elevator 4a and the boat 3 placed thereon to be raised or lowered.

This rising or falling boat 3 is a reflection type displacement sensor 1
If this displacement sensor 15 does not detect a displacement within a predetermined distance from the boat 3, the main controller 18 determines that the state of the boat 3 is normal; if a displacement is detected, the main controller 18 Accordingly, it is determined that the boat 3 has an abnormality such as orientation, inclination, damage, deformation, etc.

If the main controller 18 determines that there is an abnormality, it issues a warning to the operator of the occurrence of the abnormality and stops the drive section driver 17. After that, the operator will perform processing when an abnormality occurs.

〔Example〕

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

FIG. 1 is a schematic perspective view of the internal structure of a vertical diffusion/CVD apparatus to which the present invention is applied.

The heater 1 heats the wafer within the reaction chamber 8. Reference numeral 4 denotes a boat elevator main body for loading and unloading the boat 3 on which the wafers 2 in the reaction chamber 8 are placed. 5
transfers wafer 2 from cassette to boat 3 and transfers wafer 2 from cassette to boat 3.
A wafer transfer machine is used to transfer the wafers 2 from the wafers 2 to the cassettes, and 6 is a furnace port shutter that prevents radiant heat and air from being drawn in from the furnace port 9 during the transfer of the wafers 2 . 7 is a cassette stocker for storing cassettes. 10 is a wafer number counting device. Boat position detection device 14 according to this embodiment
is provided in the boat elevator main body 4.

The cassette stocker 7 is movable in the horizontal direction with respect to the wafer transfer machine 5, and the transfer machine 5 includes a horizontal movement mechanism section 11 that moves the wafer chuck in the horizontal direction;
It is equipped with an elevating mechanism 912 for elevating and lowering, and a rotating mechanism section 13 for further rotation.

Next, the configuration of the boat position detection device 14 of the present invention will be explained.

In FIGS. 2 to 4, a reflection type ultrasonic displacement sensor 15 for boat monitoring whose distance to the boat 3 is determined is attached to the boat elevator main body 4.

The boat 3 is placed on a boat elevator 4a.

Reference numeral 19 represents an operation unit through which an operator operates, sets, and registers the operation of the boat elevator 4a and displays the current status, etc., and 17 represents a motor driver that operates the motor 20 that manually inputs an operation instruction signal to raise and lower the boat elevator 4a. .

18 has a function of outputting an operation instruction signal to the motor driver 7 by operating, setting, and registering the operation unit 19, and when the reflective ultrasonic displacement sensor 15 does not detect displacement within a predetermined distance from the boat 3, the boat 3 3 is determined to be normal, and if displacement is detected, it is determined that there is an abnormality such as the orientation, inclination, damage, or deformation of the boat 3. If it is determined that there is an abnormality, the operator is alerted to the occurrence of an abnormality. This is the main controller that emits a signal and stops the motor driver 17.

A rotary encoder 21 detects the amount of movement, speed, etc. of the boat elevator 4a as the amount of rotation. The output signal of the rotary encoder 21 is input to the main controller 18 via the motor driver 17, and is used to determine whether it is normal or abnormal. The pulse interval of the output of the reflective ultrasonic displacement sensor 15 changes depending on the speed and amount of movement of the boat 3, so it is not always necessary to determine whether it is normal or abnormal, but by taking this into consideration, it can be determined whether it is normal or not. , which is preferable because it can further improve the accuracy in determining abnormalities.

Next, the operation of the boat position detection device 14 will be explained.

FIG. 2 is a diagram showing the boat 3 being transferred to the boat elevator 4a. After confirming that the position of the boat 3 is correct using the reflective ultrasonic displacement sensor 15 that has registered the distance to the boat 3 in advance, the boat elevator 4a
The boat 3 is raised to load the reaction chamber 8 of the heater 1.

FIG. 3 shows a state in which the boat 3 is being loaded toward the reaction chamber 8 by the boat elevator 4a. Boat position detection by the reflection type ultrasonic displacement sensor 15 is performed only at a location that should be the same as a previously registered distance. Therefore, the upper end and lower end of the boat 3 are excluded from position detection.

When loading from the state shown in FIG. 2 to the state shown in FIG. 3, the boat 3 is vertically raised by the boat elevator 4a, so the distance between the reflective ultrasonic displacement sensor 15 and the boat 3 is the same. If the reflective ultrasonic displacement sensor 15 detects a displacement with respect to the distance to the boat 3, the boat 3 is facing the wrong direction, is tilted, is damaged, or is deformed, or the position of the boat elevator 4a is determined. Either one or the other. The orientation, inclination, damage, and deformation of the boat 3 are abnormalities of the boat 3, and the boat elevator 4a of the boat 3
If the boat elevator 4a is displaced, maintenance of the boat elevator 4a is required. Therefore, when the reflective ultrasonic displacement sensor 15 detects a displacement in the distance between the reflective ultrasonic displacement sensor 15 and the boat 3, it is assumed that an abnormality has occurred in the position or state of the boat 3, and an alarm is issued to the operator.
The operation of the boat elevator 4a is stopped.

The unloading of the boat 3 from the reaction chamber 8 is as shown in FIG.
The boat elevator 4a moves to the state shown in the figure. The steps are
The opposite is true for loading.

The operation of the boat elevator 4a is operated, set, and registered by an operator using the operating section 19, and the current state and the like are displayed on the operating section 19.

The main controller 18 instructs the motor driver 17 to operate through operations, settings, and registration. Motor driver 17 operates motor 20 according to instructions from main controller 18 .

The boat elevator 4a is raised and lowered by the operation of the motor 20. The boat 3 is placed in a boat elevator 4a, and the state of the boat 3 is detected by a reflective ultrasonic displacement sensor 15, and the detected state is sent to the sensor control unit 1.
6, the main controller 18 is notified. The amount of movement and speed of movement of the boat elevator 4a are determined by the motor 2.
The rotation is detected by the rotary encoder 21 as zero rotation, and is notified to the main controller 18 via the motor driver 17.

The main controller 18 detects the state of the boat 3, the amount of movement of the boat elevator 4a, the speed of movement, etc., determines the validity of the state of the boat 3, confirms the abnormal operation state, and when it is determined that there is an abnormality. issues a warning to the operator of the occurrence of an abnormality, stops loading and unloading operations of the boat elevator 4a, and the operator performs processing when the abnormality occurs.

Next, the principle of boat position detection will be explained.

FIG. 5 is a diagram illustrating an example of the structure of the reflective ultrasonic displacement sensor 15 and the principle of boat position detection.

The sensor control unit 16 controls a pulse transmitting circuit 22 and a pulse receiving circuit 23. The ultrasonic waves emitted from the transmitting transducer 24 are reflected by the boat 3 and received by the receiving transducer 25. If the emitted ultrasonic waves cannot be received, it can be determined that there is no boat. Furthermore, a change in the distance to the boat 3 can be detected based on a change in the strength of the received ultrasonic wave with respect to the transmission of a constant strength.

Note that the reflection type ultrasonic displacement sensor used in this device is a commercially available one.

Finally, as an application example of this device, it is also possible to fix the boat 3 and move the reflective ultrasonic displacement sensor 15 to detect whether there is an abnormality in the boat.

Thus, the present invention uses the reflective displacement sensor 15 attached to the boat elevator body 4 to automatically check the orientation, inclination, damage, deformation, etc. of the boat 3 on the boat elevator 4a, instead of having the operator visually check the orientation, inclination, damage, deformation, etc. Act accordingly,
When an abnormality in the boat position is detected, a warning is issued to the operator, and the raising and lowering operations of the boat elevator 4a are stopped, and the controller is used to perform processing when an abnormality occurs.

〔Effect of the invention〕

As described above, according to the present invention, the boat 3 on the boat elevator 4a can be monitored by the reflective displacement sensor 15 attached to the elevator main body 4, so that the operator can monitor the direction, inclination, etc. of the boat 3 on the boat elevator 4a. Corruption,
There is no need to visually monitor deformation, etc., and there is no risk of errors due to different judgments by the operator, and the boat maintains normal operation even when the operation of the boat elevator 4a is not visible.

An abnormality can be determined, and if it is determined to be abnormal, the abnormal operation is stopped, and the operator can take measures to recover from the abnormal state.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view of the internal configuration of a vertical diffusion/CVD apparatus that is the object of the present invention, FIG. 2 is a diagram showing a state in which a boat according to the present invention is transferred to a boat elevator, and FIG. A diagram showing a state in which a boat is being loaded toward a reaction chamber by a boat elevator according to the present invention, FIG. 4 is an explanatory diagram showing the configuration of an embodiment of the apparatus according to the present invention, and FIG. FIG. 2 is a configuration explanatory diagram of an example of a sensor. 1... Heater, 2... Wafer, 3.
...Boat, 4...Boat elevator,
4a... Boat elevator, 5... Wafer transfer machine, 6... Furnace shutter, 7...
-...Cassette stocker, 8...Reaction chamber, 9.
... Furnace mouth, 10 ... Wafer number counting device, 11 ... Horizontal movement mechanism section, 12 ...
- Lifting mechanism section, 13...Rotation mechanism section, 14...
... Boat position detection device, 15 ... Reflection type (ultrasonic) displacement sensor, 16 ... Sensor control section, 17 ... Motor driver, 18 ...
...Main controller, 19...Operation unit, 2
0...Drive unit (motor), 21...Movement amount/movement speed detector (rotary encoder)

Claims (1)

[Scope of Claims] [1] A reflective displacement sensor for boat monitoring (with a determined distance to the boat (3)) on the boat elevator main body (4).
15) is installed, and if this reflective displacement sensor (15) does not detect any displacement within a predetermined distance from the boat (3), it is determined that the boat (3) is in a normal condition. It is determined that there is an abnormality such as orientation, inclination, damage, deformation, etc. of the boat (3), and if it is determined that there is an abnormality, an abnormality warning is issued to the operator and the boat elevator (4a)
A boat position detection method characterized in that the raising and lowering operations of the boat are stopped and processing is performed when an abnormality occurs. [2] The boat position detection method according to claim 1, characterized in that the movement amount, movement speed, etc. of the boat elevator (4a) are introduced into the determination of normality and abnormality. [3] A reflective displacement sensor (15) attached to the boat elevator main body (4) for boat monitoring with a fixed distance to the boat (3) and an operation instruction signal input to raise and lower the boat elevator (4a). It has a function of outputting an operation instruction signal to the drive unit driver (17) and a drive unit driver (17) that operates the drive unit (4a) that performs If no displacement is detected within a predetermined distance, it is determined that the boat (3) is in a normal condition, and if displacement is detected, the direction, inclination, and direction of the boat (3) are determined.
The boat position detection device is comprised of a main controller (18) that determines that there is an abnormality such as damage or deformation, and when it is determined that there is an abnormality, issues an alarm of the occurrence of the abnormality to the operator and stops the drive unit driver (17). [4] A detector (21) is provided to detect the amount of movement, movement speed, etc. of the boat elevator (4a), and this detector (21)
A boat position detection device configured to input the output signal of 1) to a main controller (18) via a drive unit driver (17).