JPH11145071A - Semiconductor manufacturing equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a temperature detection precision of thermocouples and control precision based on the thermocouples, by preventing the compensation contact points of the thermocouples and compensation conductors from being affected by heat disturbance. SOLUTION: A temperature of a reaction pipe 11 is controlled by a temperature control circuit 15 controlling the supply power of a heater 12 in accordance with the detection output of the thermocouples 13. Compensation conductors 16 connected to the temperature control circuit 15 are provided in a radiator room 22. Thermocouple wires 14 similar to the thermocouples 13 are connected to the thermocouples 13 inserted into the heater 12, and they are taken around in a heater room 21 so as to extend them to the radiator room 22. The compensation conductors 16 and the thermocouple wires 14 are connected in the radiator room 22. Compensation contact points 17 being the connection parts are screwed to the up stream side of a cooling water supply pipe 19 through an electric insulating object so as to brought them in contact each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus provided with a temperature control system, and more particularly to a semiconductor device capable of detecting and controlling temperature with high accuracy.

[0002]

2. Description of the Related Art FIG. 3 is a perspective view showing an entire vertical diffusion / CVD apparatus, which is one of semiconductor manufacturing apparatuses, viewed obliquely from behind. 2 is a main body for processing the wafer, and 3 is a control unit for controlling the main body 2. Although not shown in the figure, a load lock chamber is provided in a lower portion of a rear portion of the main body 2, and a vertical reaction chamber is provided in an upper portion thereof. A heater chamber exhaust duct 5 is led out of the heater chamber 4 of the vertical reaction chamber to discharge hot air from the heater chamber 4. In addition, a cooling water supply pipe 7 and a cooling water discharge pipe 8 are led out from the radiator chamber 6 to cool a non-heated portion in the radiator chamber 6.

FIG. 4 is a schematic configuration diagram of the temperature control system for the vertical reaction chamber described above. Reaction tube 1 for processing wafers
A heater 12 is provided on the outer periphery of the tube 1 so that the inside of the reaction tube 11 can be heated. The heater temperature can be detected by the thermocouple 13. Thermocouple 13 and temperature control circuit 1
5, a thermocouple element wire extending from the thermocouple 13 itself is used from the temperature measuring section of the thermocouple 13 to the vicinity of the heater 12, and a less expensive thermocouple is used from the vicinity of the heater 12 to the temperature control circuit 15. It is guided by a compensating lead 16 having substantially the same characteristics as the pair. The electromotive force generated in the temperature measuring part of the thermocouple 13 is the thermocouple 13
Contact 17 which is a contact between the dissimilar metal and the compensating conductor 16
Through the compensating lead 16 to the temperature control circuit 15. The temperature control circuit 15 detects the temperature of the heater 12 from the introduced electromotive force, and performs feedback control of the power applied to the heater 12 in accordance with the detected heater temperature to make the temperature distribution in the reaction tube 11 uniform.

Further, a heater 12 including an upper part of a reaction tube 11 is provided.
A cooling plate 18 is provided at an upper portion of the heater 12 and a lower portion of the heater 12, and cooling water is supplied to the cooling plate 18 from a cooling water supply pipe 19 and discharged from a cooling water discharge pipe 20 to cool the cooling plate 18. The upper and lower portions of the heater 12 can be cooled so that the heater 12 does not overheat.

[0005] Of the space occupied by the reaction tube 11, the heater 12, the cooling plate 18, the cooling water supply pipe 19, and the cooling water discharge pipe 20, the upper space in which the heater 12 is housed is the heater chamber 2.
The space in which the cooling water supply pipe 19 and the cooling water discharge pipe 20 are arranged is a radiator chamber 22.

[0006]

The thermocouple 13
The heater chamber 21 having the compensation contact 17 has a high temperature and is easily affected by a temperature change due to thermal disturbance. Here, there are mainly two types of thermal disturbance.

(1) Due to Change in Wafer Processing Temperature The temperature at which a wafer is processed in the reaction tube 11 may be 1000 ° C. or 1150 ° C. even in the same semiconductor manufacturing apparatus. When the temperature of the heater 12 changes accordingly, the amount of heat radiation from the heater surface also changes, and the temperature inside the heater chamber 21 changes.

(2) Due to a change in the exhaust amount of the heater chamber exhaust duct In order to prevent a temperature rise due to heat radiation from the heater surface, the heater chamber 21 is provided with a heater chamber exhaust duct (see reference numeral 5 in FIG. 3).
It is exhausted by. Although the heater chamber exhaust duct 5 is connected to the equipment in the factory, the exhaust air volume on the equipment side may change because it is finally combined with other semiconductor manufacturing equipment. When the amount of exhaust air from the duct 5 changes, the temperature in the heater chamber 21 changes.

As described above, the temperature of the heater chamber 21 changes due to disturbance. In particular, the compensating contact 17 of the thermocouple 13 is located near the heater 12 having a large temperature change, and the compensating contact 17 itself is directly affected by the heater 12, so that the temperature change is large. Further, since the compensating conductor 16 is provided in the heater chamber 21, it receives a temperature change due to disturbance. As a result, thermocouple 1
3 has a problem that the temperature detection accuracy is deteriorated and the temperature control accuracy is thereby lowered.

An object of the present invention is to solve the above-mentioned problems of the prior art by preventing the compensation contact and the compensation conductor from being affected by thermal disturbance, thereby improving the temperature detection accuracy and control accuracy. It is to provide a manufacturing apparatus.

[0011]

In order to achieve the above object, it is necessary that a conductor led from a thermocouple to a temperature control circuit is not affected by thermal disturbance and has no temperature gradient along the conductor. Good. To avoid the influence of thermal disturbance and eliminate the temperature gradient, (1) Change the connection with the thermocouple in the heating chamber from the conventional compensating conductor to the same thermocouple wire as the thermocouple,
(2) The thermocouple wire may be routed to the vicinity of the heat radiating chamber, connected to the compensating conductor, and brought into contact with a cooling system having a small temperature change.

Therefore, the present invention provides a heating chamber having a heating system for heating a portion to be heated, a radiating chamber having a cooling system for cooling a non-heating portion heated by the heating system, A temperature control circuit for controlling power supplied to the heating system in accordance with the temperature of the heated portion, wherein a compensating lead connected to the temperature control circuit is disposed in the heat radiating chamber; The same thermocouple element as the thermocouple is connected to the thermocouple, and this is extended from the heating chamber to the radiating chamber.The extended thermocouple element and the compensating lead wire arranged in the radiating chamber are connected, and The compensating contact, which is the connection point between the thermocouple element wire and the compensating conductor, is brought into contact with the cooling system, which has a small temperature change.

When a thermocouple element is used in the heating chamber, it is not affected by thermal disturbance. In particular, when the compensating contact of the thermocouple, which easily causes a measurement error, is brought into contact with the cooling system, the temperature of the compensating contact is suppressed by the cooling system. When the compensating conductor is placed in the heat dissipation chamber,
Temperature gradients are unlikely to occur along the compensating lead. Therefore,
A thermoelectromotive force with a small error is sent from the thermocouple to the temperature control circuit.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described below with reference to vertical diffusion / CVD.
An embodiment applied to an apparatus will be described.

FIG. 1 shows a schematic configuration diagram of a temperature control system for a vertical reaction chamber. The upper part 12a of the heater 12 including the upper part 11a of the reaction tube 11 which becomes the non-heating part which should not be overheated
The cooling plate 18 is provided on each of the heater 12 and the lower portion 12 b of the heater 12. The upper and lower portions of the heater 12 can be cooled by supplying cooling water from the cooling water supply pipe 19 to the cooling plate 18 and discharging the cooling water from the cooling water discharge pipe 20 to cool the cooling plate 18. The cooling plate 18 and the cooling water supply pipe 1
9. A cooling system is constituted by the cooling water discharge pipe 20. The non-heating portion is constituted by the upper portion 11a of the reaction tube, the upper portion 12a of the heater, and the lower portion 12b of the heater.

A heater 12 as a heating system divided into a plurality of zones in the axial direction of the tube is installed on the outer periphery of the reaction tube 11 to be heated, so that the inside of the reaction tube 11 can be heated for each zone. I have. By inserting a thermocouple 13 into each heater 12, the heater temperature can be detected. The same thermocouple wires 14 as the thermocouples drawn from the thermocouples 13 are extended and guided into a radiator chamber 22 as a heat radiating chamber via a heater chamber 21 as a heating chamber to supply cooling water in the radiator chamber 22. Route to pipe 19. Here, the thermocouple wire 14 is connected to a compensating lead wire 16 which is less expensive and has substantially the same characteristics as the thermocouple used, and the connection point, which is the connection point, is brought into contact with the cooling water supply pipe 19. From here, the temperature control circuit 15 is guided by a compensating conductor 16, and the compensating conductor 16 is disposed in the radiator chamber 22 having a low temperature.

The electromotive force generated in the temperature measuring section of each thermocouple 13 passes through the thermocouple wire 14, passes through the compensation contact 17, and passes through the compensation conductor 16.
It is introduced into the temperature control circuit 15. Temperature control circuit 15
Detects the heater temperature from the introduced electromotive force, controls the power applied to each heater 12 according to the heater temperature in a feedback manner, and makes the temperature distribution in the reaction tube 11 uniform.

FIG. 2 shows the details of the connection of the compensation contact 17. An electrical insulator 23 is attached to an outer wall of the cooling water supply pipe 19 on the upstream side, and a screw hole is formed in the electrical insulator 23. A loop is formed at the end of the thermocouple wire 14 leading to the cooling water supply pipe 19 and the end of the compensating wire 16 and overlapped with each other. A screw 24 is inserted into this loop, and the tip of the screw 24 is screwed into a screw hole. The strand 14 and the compensating lead 16 are fastened and fixed to the cooling water supply pipe 19.

As described above, the connection with the thermocouple 13 in the heater chamber 21 is changed from the conventional compensating conductor to the same thermocouple wire 14 as the thermocouple 13, so that the heat disturbance in the heater chamber 21 is prevented. , And a temperature gradient along the thermocouple wire 14 is unlikely to occur.

Further, the thermocouple wire 14 is routed to the vicinity of the radiator chamber 22 where the cooling water supply pipe 19 is provided and connected to the compensating conductor 16, so that the cooling water temperature is usually about 20 ° C. and the temperature change is small. Since the compensating contact 17 is brought into contact with the upstream side of the pipe 19 via the electrical insulator 23, the temperature of the compensating contact 17 is stably maintained at a low temperature, and the compensating contact itself does not fluctuate in temperature. .

Further, since the compensating conductor 16 connected to the thermocouple element wire 14 is arranged in the radiator chamber 22, a temperature gradient is hardly generated along the compensating conductor 16, and even if it does occur, it is originally generated. Since the radiator chamber 22 has a low temperature and a low temperature gradient, an error hardly occurs.

Accordingly, the temperature change of the compensating contact is reduced and the error caused by the parasitic electromotive force is reduced as compared with the conventional one in which the thermocouple and the compensating conductor are connected in the heater chamber. The temperature detection accuracy and the control accuracy of the heater 12 controlled by the detection output of the thermocouple 13 are improved, and thus the reproducibility of the film formation is improved.

The portion to be heated is not limited to a reaction tube, but may be applied to any space or chamber heated by a heater. The heater constituting the heating system may be any of resistance heating, lamp heating, and high-frequency heating. Thermocouples are known. The temperature control circuit controls the power applied to the heater by controlling the phase of the gate of the thyristor, for example, according to the detection result of the thermocouple. The cooling system for bringing the compensating contact into contact may be a cooling water discharge pipe, but is preferably a cooling water supply pipe because of its low and stable temperature, and more preferably on the upstream side. In the embodiment, the cooling water supply pipe is attached. However, a support section thermally connected to the cooling water supply pipe may be used. Further, the cooling water pipe is not limited to the heater. Other cooling water piping for cooling the non-heating part in the apparatus, or an equivalent thereof may be used. Further, the semiconductor manufacturing apparatus is not limited to vertical diffusion / CVD. For example, plasma CVD
The present invention can be applied to any device in which a cooling system is introduced into the apparatus.

[0024]

According to the present invention, a thermocouple element is disposed in a heating chamber having a high thermal disturbance at a high temperature, and a compensating conductor is disposed in a heat radiation chamber which is stable at a relatively low temperature. The temperature of the compensation contact is stabilized at a low temperature by contacting the contact with the cooling system, so the effect of thermal disturbance applied to the wire leading from the thermocouple to the temperature control circuit can be reduced, and the temperature detection accuracy and control by the thermocouple Accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a temperature control system of a vertical reaction chamber according to an embodiment.

FIG. 2 is an enlarged explanatory view of a main part of a compensation contact screwed to a cooling water supply pipe.

FIG. 3 is a schematic configuration diagram of a vertical diffusion / CVD apparatus.

FIG. 4 is a schematic configuration diagram of a conventional temperature control system for a vertical reaction chamber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Reaction tube (heated part) 12 Heater (heating system) 13 Thermocouple 14 Thermocouple wire 15 Temperature control circuit 16 Compensation lead wire 17 Compensation contact 18 Cooling plate 19 Cooling water supply pipe 21 Heater room (heating room) 22 Radiator room (Heat dissipation chamber) 23 Electrical insulator

Claims (1)

[Claims] 1. A heating chamber having a heating system for heating a heated portion, a radiating room having a cooling system for cooling a non-heated portion heated by the heating system, and the heated portion detected by a thermocouple. A semiconductor manufacturing apparatus comprising: a temperature control circuit that controls power supplied to the heating system according to a temperature; a compensating lead wire connected to the temperature control circuit is disposed in the heat radiation chamber; Connect the same thermocouple wire as the pair, extend it from the heating chamber to the heat radiating chamber, connect the extended thermocouple wire and the compensating wire arranged in the heat radiating chamber, and connect the thermocouple wire. And a compensating contact, which is a connection point between the compensating conductor and the compensating conductor, is brought into contact with the cooling system having a small temperature change.