JPH08210923A - Furnace temperature measuring device for heating furnace - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide an in-furnace temperature measuring instrument of a reduced pressure heating furnace capable of measuring a temperature distribution in the reduced pressure heating furnace even when the inside of the reduced pressure heating furnace is in a reduced pressure state. [Structure] A heater 1 is provided outside the furnace body 11 of the decompression heating furnace.
2 and the outside-of-furnace temperature measuring device 15, the inside-of-furnace temperature measuring device 30 is provided inside the furnace body 11, and the temperature difference between the inside and outside of the furnace body 11 at the time of heating by the heater 12 is previously measured as calibration data, In the actual manufacturing operation, the decompression heating furnace is a decompression heating furnace in which the temperature measured by the outside temperature measuring device 15 is calibrated by the calibration data, and the temperature inside the furnace is controlled based only on this calibration data. , Inserted into the furnace body 11,
A protective tube 31 having a closed front end inside the furnace body 11 and an open base end outside the furnace body 11, a support tube 33 movably inserted from the base end opening of the protective tube 31, and a support tube 33 inserted through the support tube 33. It is composed of the supported thermocouple wires 32a and 32b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to semiconductor manufacturing CVD.
Heating furnaces used in equipment and diffusers, etc., in particular, the temperature inside the furnace that is difficult to measure during manufacturing is measured in advance to create calibration data, and only the temperature outside the furnace is measured during manufacturing, and the temperature outside the furnace is measured. The present invention relates to an in-furnace temperature measuring device for a heating furnace, which calibrates the temperature in accordance with the calibration data and controls the in-furnace temperature based on the calibrated temperature.

[0002]

2. Description of the Related Art For example, in a CVD apparatus, a substrate such as a silicon wafer is housed in a reduced pressure heating furnace, and this substrate is heated to a predetermined temperature under reduced pressure to form a thin film. Conventionally,
As a reduced pressure heating furnace used in such a CVD apparatus,
Those described in FIGS. 4 to 6 are known. FIG.
In the figure, 11 is a furnace body, and 12 is a heater provided on the outer periphery of the furnace body 11. The furnace body 11 has a hollow shape with one end opened, and the opening is closed by a furnace port cap 13. As is well known, the substrate to be processed is housed in the furnace body 11 and heated by the heater 12 under reduced pressure to form a thin film on the substrate. The heater 12 is connected to a controller (not shown) and is controlled by this controller to heat the inside of the furnace body 11.

The heater 12 is provided with an out-of-furnace temperature measuring device 15 composed of a thermocouple, and the furnace mouth cap 13 is provided with an in-furnace temperature measuring device 20. These temperature measuring devices 15, 20 are connected to the controller. . As shown in FIGS. 5 and 6, the in-furnace temperature measuring device 20 includes a bush 13 on the furnace port cap 13.
The quartz protective tube 21 is fixed to the quartz protective tube 21 and penetrates through the bush 13a so that the quartz protective tube 21 can be projected and retracted in the furnace body 11 (the projecting length can be adjusted).
A pair of thermocouple wires 22a, 22b protected by 3b
It is configured by arranging each. The quartz protection tube 21 has a large diameter portion on the outer periphery of the base end that fits with the bush 13a, and the base end opening is closed by the plug 18. The connecting portion between the plug 18 and the quartz protection tube 21 is covered and fixed by the shrinkage Teflon tube 17.

As shown in detail in FIG. 6 (b), the insulating pipes 23a and 23b are provided such that the joints of the insulating pipe 23a and the joints of the insulating pipe 23b are alternately located, and each strand is connected at the joint. The contact between 22a and 22b is prevented.
The thermocouple wires 22a and 22b have their tips welded, and pass through the plug 18 and are pulled out from the quartz protection tube 21. Thermocouple wires 22a, 22b drawn from the quartz protection tube 21
Is protected by a Teflon sleeve 28 and relayed by a silicon tube (crimp terminal) 27 to form a lead wire 29.
Connected to The lead wire 29 is connected to the controller by the terminal connector 26.

In such a vacuum heating furnace, the furnace body 11 is heated by the heater 1 prior to the formation of the thin film (manufacturing operation).
2 and the temperature outside the furnace body 11 in this case is measured by the outside temperature measuring device 15, and at the same time, the inside temperature measuring device 20 is moved up and down as shown by the arrow in FIG. The temperature distribution in the vertical direction in the body 11 is measured by the in-furnace temperature measuring device 20, and calibration data is created in advance from the measurement data of these temperature measuring devices 15 and 20 (creating calibration data). Then, during the manufacturing operation, the in-furnace temperature measuring device 20 is removed to close the hole in the bush 13a, and the temperature is measured only by the out-of-furnace temperature measuring device 15. Then, the temperature measured by the outside temperature measuring device 15 is calibrated to the temperature data inside the furnace body 11 based on the calibration data, and the heater 12 is controlled by this calibrated data.

[0006]

However, in the above-mentioned reduced pressure heating furnace, when creating the calibration data,
When the in-furnace temperature measuring device 20 is lowered downward, a gap is created between the bush 13a and the quartz protection tube 21. Therefore, the temperature inside the furnace body 11 is measured under reduced pressure, or the temperature is maintained in an airtight state. There is a problem that measurement is impossible and calibration data that matches the conditions of the actual manufacturing operation cannot be obtained.

The present invention has been made in view of the above problems, and it is possible to measure the temperature inside the furnace body in a depressurized state and to obtain calibration data that matches actual operating conditions. An object is to provide a temperature measuring device.

[0008]

In order to achieve the above-mentioned object, a furnace temperature measuring instrument for a heating furnace according to the present invention has a tip closed and a base end opened, and a closed end from an insertion port in a furnace. A protective tube that is hermetically inserted, a support tube that is inserted into the protective tube so that the insertion length can be adjusted from the base end opening, and a pair that is installed in the support tube and joined at the tip of the support tube And a thermocouple wire.

[0009]

According to the decompression heating furnace of the present invention, the protective tube projects into the furnace body while maintaining the airtightness, and the support tube having the thermocouple wire installed therein is movably inserted into the protective tube. Even if the furnace body is in a depressurized state, by moving the support tube in the protective tube while the protective tube is airtightly attached to the furnace body, the temperature of each layer in the furnace body while maintaining the depressurized state in the furnace body, that is, The temperature distribution can be measured, and calibration data close to actual manufacturing conditions can be obtained.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show an in-furnace temperature measuring instrument for a heating furnace according to an embodiment of the present invention, and FIG. 1 is a cross-sectional view of the in-reactor temperature measuring instrument, which is a main part thereof, and FIGS. FIG. 3B is an enlarged perspective view of a part of the in-furnace temperature measuring device, and FIG. 3 is a sectional view for explaining the operation. In addition, FIG. 4 to FIG.
The same parts as those of the decompression heating furnace shown in FIG.

In FIG. 1, reference numeral 30 denotes an in-furnace temperature measuring device. The in-reactor temperature measuring device 30 is movably inserted through a support pipe 33 in which thermocouple wires 32a and 32b are installed in a protective pipe 31. Configured. The protection tube 31 is made of a highly heat-resistant material such as quartz, SiC (silicon carbide), alumina, or ceramics, has a closed front end, an open base end, and a large-diameter portion with an expanded outer diameter on the base end side. 31a and the attachment flange part 31b are formed. When the furnace is used under a considerably high temperature condition of 1000 ° C. or higher, it is preferable to form the protective tube 31 with SiC or alumina having high heat resistance. The protective tube 31 penetrates through the bush 13a of the furnace port cap 13 and its tip projects up to the upper part in the furnace body 11,
The large diameter portion 31a is airtightly fitted to the bush 13a, and the base end opens outside the furnace body 11.

The support tube 33 is made of a material having an insulating property and a high heat resistance such as ceramics, and has two insertion holes 3 inside.
3a and 33b are formed separately from each other. A protective member 35 is provided at the tip of the support tube 33, and a substantially disc-shaped mounting flange 36 is fixed at the base end. This support tube 3
3 is detachably fixed to the protective tube 31 by screwing a nut 42 onto a bolt 41 that penetrates the mounting flange 36 and the mounting flange portion 31b of the protective tube 31 described above.
The protective member 35 has a V-shaped groove 35a formed at its tip,
As will be described later, the thermocouple wire 3 is provided between the side surfaces of the groove 35a.
The tip welds of 2a and 32b are located.

The thermocouple wires 32a and 32b are shown in FIG.
As shown in (a) and (b), the insertion hole 33 of the support tube 33 is formed.
The tip portions of the a and 33b electrically insulated from each other and extending from the tip of the support tube 33 pass through the protective member 35 and are welded in the groove 35a. These thermocouple wires 32a and 32b are routed to the outside through a mounting flange 36, and are connected to a controller (not shown) via lead wires 29 and terminal connectors 26, as in the above-described conventional example.

In the in-furnace temperature measuring device 30 of this embodiment, the protection tube 31 is inserted into the furnace body 11 and the large diameter portion 31a is formed.
Is fitted to the bush 13a, and is attached to the furnace body 11 while maintaining airtightness. In addition, the support pipe 33 includes a mounting flange 36 and a mounting flange portion 31b of the protective pipe 31.
By connecting and with the bolt 41 and the nut 42,
It is fixed in a state of being inserted into the protection tube 31. And
The support tube 33 can be moved vertically in the protective tube 31 by removing the bolts 41 and the nuts 42, and the tip welded portions of the thermocouple wires 32a and 32b can be moved in the protective tube 31 in the vertical direction of the furnace body 11. Can be moved to. When the support tube 33 is moved, the thermocouple wires 32a and 32b are moved.
Since the tip welded portion is located inside the V-shaped groove 35a of the protection member 35, it is possible to prevent the tip welded portion from rubbing against the inner surface of the protective tube 31 or the like.

Therefore, when creating the above-mentioned calibration data, even if the inside of the furnace body 11 is decompressed, the large-diameter portion 31a and the bush 13a are fitted to each other, so that the furnace body 11 is kept airtight. The support tube 33 can be freely moved up and down. Therefore, the temperature distribution inside the furnace body 11 can be measured by the in-furnace temperature measuring device 30 without any trouble, and the calibration data that matches the conditions of the actual manufacturing operation can be created. As a result, in the actual manufacturing operation, even if the temperature measuring device 30 inside the furnace is removed and the temperature is measured only by the temperature measuring device outside the furnace 15, the inside of the furnace body 11 is based on the measured temperature data and the calibration data. Accurately grasp the temperature of the heater 1
2 can be controlled accurately.

In the above-described embodiment, the large diameter portion 31a is formed in the protective pipe 31 so as to be fitted to the bush 13a. However, the protective pipe 31 is configured to have the same diameter as the large diameter portion 31a. It is also possible to do so. Further, in the above-described embodiment, the furnace temperature measuring device 30 is described as being used only for creating the calibration data, but the furnace temperature measuring device 30 is inserted and attached in the furnace body 11 even during the manufacturing operation. It can also be used for controlling the temperature in the furnace during the manufacturing operation. Further, in the above-described embodiment, the furnace temperature measuring device 30
Although it has been described that one is provided, a plurality of may be provided.

Further, in the above-mentioned embodiment, the description of the method of moving the support pipe 33 when measuring the temperature distribution in the furnace body 11 is omitted, but the movement of the support pipe is manually performed by an operator. Alternatively, it can be configured in various forms such as automatically using a drive mechanism. Further, in the above-described embodiment, the furnace temperature measuring device 30 is used as the furnace body 1.
Although the example in which the furnace temperature measuring device 30 is vertically installed and used in the vertical direction has been described, the in-furnace temperature measuring device 30 can be installed and used in any direction such as a horizontal direction or an oblique direction. Further, in the above-described embodiment, the example in which the furnace temperature measuring device 30 is applied to the vertical decompression heating furnace has been described.
The present invention can be widely applied to a furnace heating type apparatus such as a CVD apparatus or a diffusion furnace, regardless of whether the inside of the furnace is depressurized or whether the furnace is vertical type or horizontal type.

[0018]

As described above, according to the in-furnace temperature measuring device for a heating furnace according to the present invention, a protective tube is thrust into the furnace body to be airtightly provided, and the furnace body is protected airtightly. The support tube was attached to the protection tube so that a pair of thermocouple wires were electrically insulated and inserted through the protection tube, so that the support tube was moved even when the furnace was under reduced pressure. As a result, it is possible to measure the temperature distribution in the furnace body, and it is possible to create accurate data that more closely matches actual operating conditions when creating calibration data. As a result, temperature control in semiconductor manufacturing can be accurately performed, and high quality products can be manufactured with high yield.

[Brief description of drawings]

FIG. 1 is an overall sectional view showing an in-furnace temperature measuring instrument for a heating furnace according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a tip portion of a support tube of the in-furnace temperature measuring instrument, in which (a) shows a protective member attached state and (b) shows a protective member unattached state.

FIG. 3 is an operation explanatory view showing an operation of the in-furnace temperature measuring device.

FIG. 4 is a diagram schematically showing an overall configuration of a heating furnace to which the present invention is applied.

FIG. 5 is a schematic diagram of a furnace temperature measuring device in a conventional reduced-pressure heating furnace.

FIG. 6 shows the same conventional furnace temperature measuring instrument, in which (a) is a sectional view thereof and (b) is a partially enlarged view thereof.

[Explanation of symbols]

 11 Furnace Body 12 Heater 13a Bush 15 Outer Temperature Measuring Device 30 Inner Temperature Measuring Device 31 Protective Tube 32a, 32b Thermocouple Element 33 Support Tube

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical indication location G01K 1/14 J 7/00 321 C 15/00 H01L 21/205 21/22 501 N 21/324 D H05B 3 / 00 310 E

Claims (1)

[Claims] 1. A protective tube having a closed front end, an open base end, and a closed end airtightly inserted from an insertion port into a furnace body,
A protective tube that is inserted into the protective tube from its base end opening so that the insertion length can be adjusted; and a pair of thermocouple wires that are routed to the supporting tube and joined at the tip of the supporting tube. Characteristic in-furnace temperature measuring device for heating furnace.