JPH087459Y2 - Scavenger heat exhaust automatic control system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to a semiconductor manufacturing apparatus, and more particularly to an apparatus for automatically controlling the heat exhaust amount of a scavenger.

2. Description of the Related Art A wafer that has been heat-treated in a reaction furnace is carried into a scavenger in which heat is exhausted, where it is slowly cooled and then,
Transported to a clean room.

The thermal exhaust of the scavenger is always performed through a suction duct connected to the exhaust port.

Problems to be solved by the invention With the conventional scavenger, the temperature inside the scavenger becomes extremely unstable because heat is constantly exhausted, making it difficult to always maintain the scavenger at the set temperature. .

As a result, the temperature inside the scavenger becomes too low, and the wafer may be rapidly cooled and subjected to heat shock, resulting in cracking.

If the heat exhaust is too strong, a turbulent air flow is generated in the scavenger, and the air in the clean room may be trapped in the scavenger.

Therefore, in the scavenger cooling the wafer while purging with N ₂ , impurities such as oxygen adhere to the wafer,
Another film may be formed.

In view of the above circumstances, the present invention aims at automatically controlling the heat exhaust of the scavenger.

Means for Solving the Problems The present invention is directed to a quartz tube autoshutter disposed in a scavenger; a duct air flow rate adjusting device provided at an exhaust port of the scavenger; a temperature sensor provided in the scavenger; Compare the measured temperature of the sensor with the set temperature,
According to the temperature difference, a computer for controlling the duct air flow rate adjusting device and the automatic shutter is provided, and the thermal exhaust automatic control device of the scavenger is intended to achieve the above object.

The temperature inside the scavenger is always detected by the temperature sensor, but when the measured value becomes lower than the set temperature, the duct air volume adjustment device operates according to the instruction of the computer to reduce the opening of the exhaust port and reduce the heat exhaust amount. To reduce.

On the contrary, when the measured value becomes higher than the set temperature, the instruction of the computer causes the automatic shutter to be opened if the automatic shutter is closed.
The duct air volume adjusting device operates to increase the opening of the exhaust port and increase the heat exhaust amount.

Embodiments Embodiments of the present invention will be described with reference to the accompanying drawings, and the same reference numerals have the same names and functions.

A duct air flow rate adjusting device 12 is provided at the exhaust port 11 of the scavenger 10.

This adjusting device 12 is equipped with a shut-off type valve as shown in FIG. 2, and the valve body 14 is driven by the motor M to guide frame.
When moving up and down in A15, the opening 16 that communicates with the exhaust port 11
The opening degree of changes.

The valve of the duct air flow rate adjusting device 12 is not limited to the shut-off type valve, but may be a valve as shown in FIG. 3 and FIG. 4, for example.

That is, the valve of FIG. 3 is a so-called butterfly valve, and when the valve body 19 in the frame 18 is rotated in the direction of arrow A19 by the drive of the motor M, the opening degree of the opening 20 communicating with the exhaust port 11 is increased. Change. Further, in the valve shown in FIG. 4, when the valve body 22 is provided on the upper edge of the frame 20 and the valve body 22 is rotated in the direction of arrow A22 by the drive of the motor M, the opening 2 communicating with the exhaust port 11 is formed.
The opening degree of 3 changes.

Reference numeral 24 denotes a temperature sensor for measuring the temperature inside the scavenger. As the temperature sensor 24, for example, a thermocouple thermometer 24 provided on the scavenger inner wall 10a is used.

The temperature sensor 24 is connected to the motor M of the duct air volume adjusting device 12 via a computer (not shown).

Next, the operation of the embodiment will be described.
When the measured value becomes lower than the set temperature, the motor M of the duct air volume adjusting device 12 rotates in a predetermined direction to move the valve element 14 upward by the instruction of the computer, so that the opening 20 is gradually closed.

Therefore, the amount of heat exhausted from the exhaust port 11 to the duct 26 gradually decreases, and the temperature inside the scavenger increases.

Further, when the measured value of the temperature sensor 24 becomes higher than the set temperature and the auto shutter 25 is closed, the controller opens the auto shutter 25 and the motor M of the device 12 is instructed by the instruction of the computer. Since the valve element 14 can be moved downward in the opposite direction, the opening 20 is gradually opened.

Therefore, the amount of heat exhausted from the exhaust port 11 to the duct 26 gradually increases, and the temperature inside the scavenger decreases.

In addition, 27 is an automatic door that works with the automatic shutter 25, 28
Is a reaction furnace containing a reaction tube 29, and 30 is a quartz tube.

Effect of the Invention Since the invention is configured as described above, when the measured value of the temperature sensor becomes lower than the set temperature, the duct air volume adjusting device operates according to the instruction of the computer to reduce the heat exhaust amount, and vice versa. When the measured value becomes higher than the set temperature,
According to an instruction from the computer, when the automatic shutter is closed, the automatic shutter is opened and the duct air volume adjusting device is activated to increase the heat exhaust amount.

Therefore, the temperature inside the scavenger can be maintained at the set temperature.

[Brief description of drawings]

FIG. 1 is a partially sectional perspective view showing an embodiment of the present invention, and FIG.
FIG. 1 is an enlarged view of a main part of FIG. 1, FIGS. 3 and 4 are perspective views showing other embodiments, respectively, and FIG. 2 is a view corresponding to FIG. 2 and FIG. is there. 10 …… Scavenger 11 …… Exhaust port 12 …… Duct air flow controller 24 …… Temperature sensor

Claims (1)

[Scope of utility model registration request] 1. An automatic shutter for a quartz tube arranged in a scavenger; a duct air flow rate adjusting device provided at an exhaust port of the scavenger; a temperature sensor provided in the scavenger; and a temperature measured and set by the temperature sensor. A computer for comparing the temperature and controlling the duct air flow rate adjusting device and the auto shutter according to the temperature difference;