JP2009076532A - Semiconductor manufacturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor manufacturing apparatus capable of preventing failure of treated substrates because of malfunction of a heater by judging a heater replacement time while using a simple structure. <P>SOLUTION: A vertical diffusion furnace has: a cylindrical heater 11 inside a casing, and an inner tube having a boat mounted with treated substrates (works) inside the cylindrical heater 11. Upon opening a door on the casing, an external side surface 11A of the cylindrical heater 11 can be viewed from the outside. An electric heat wire inspection window 28 penetrating through a heat insulating layer 21 is provided on a U block 20D assigned to the uppermost portion of the cylindrical heater 11. That means, the electric heat wire inspection window 28 is provided so that an electric heat wire 24D disposed along the heat insulating layer 21 can be inspected from the outside of the cylindrical heater 11 while being held on electric heat wire holding members 22. Further, electric heat wire inspection window 28 is provided at a substantially intermediate position of the two adjacent electric heat wire holding members 22. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a semiconductor manufacturing apparatus.

2. Description of the Related Art Conventionally, there is a heat treatment apparatus as one of semiconductor manufacturing apparatuses used in a manufacturing process of a semiconductor wafer or the like (substrate to be processed) that forms an integrated circuit including semiconductor elements. The heat treatment apparatus is an apparatus that performs a predetermined process on a substrate to be processed by setting the substrate to be processed stored in a processing chamber inside the substrate to a predetermined high temperature. Examples of the process performed on the substrate to be processed by the heat treatment apparatus include an annealing process, a film forming process such as a thin film, and a diffusion process for diffusing impurities.

The heat treatment apparatus generates heat from a heater (heating wire) disposed around the processing chamber to raise the temperature of the processing chamber in which the substrate to be processed is stored to a target high temperature. By the way, when the heating wire is used, it deteriorates due to a secular change accompanying the use. The deteriorated heating wire causes problems such as a decrease in the amount of generated heat and disconnection, and the problems do not make it possible to suitably set the temperature of the processing chamber to a target high temperature. If a defect in the heating wire, particularly disconnection, occurs during the processing of the substrate to be processed, the temperature inside the processing chamber cannot be increased, and there is a great possibility that the substrate to be processed is defective.

Therefore, in order to prevent the substrate to be processed from being defective due to the disconnection of the heater (heating wire), a method has been proposed in which the heater (heating wire) can be suitably predicted and the heater can be replaced if necessary. (Patent Document 1).

In Patent Document 1, a power feedback unit controls a power adjustment thyristor circuit that supplies power from an AC power source to a heater. More specifically, the power feedback unit passes through the power adjustment thyristor circuit based on the measured current and voltage supplied to the heater and the temperature control signal corresponding to the measured temperature of the heater input from the temperature control unit. The power supplied to the heater is feedback controlled. The temperature control unit has a disconnection prediction function. The disconnection prediction function calculates the logical heater resistance value from the measured temperature and resistance temperature coefficient, calculates the actual heater resistance value from the measured current and measured voltage sent from the power feedback unit, and calculates the calculated logical heater resistance value. Based on the actual change rate of the heater resistance value, the possibility of the heater disconnection is determined.
JP 2006-85907 A

However, Patent Document 1 requires measurement of current, voltage, and temperature in order to determine the possibility of heater disconnection, and also requires information specific to the heating wire such as a resistance temperature coefficient. The system configuration for judging was complicated. Further, since a lot of information is required, it is not easy to apply the method for determining the possibility of disconnection of the heater to an existing heat treatment apparatus.

The present invention has been made to solve the above-described problems, and its object is to determine a heater replacement time with a simple structure and prevent a substrate to be processed from being defective due to a heater failure. An object of the present invention is to provide a semiconductor manufacturing apparatus that can be used.

The semiconductor manufacturing apparatus of the present invention is a semiconductor manufacturing apparatus that heats a substrate to be processed disposed inside the heat insulating cylinder to a target temperature by heating the heating line by means of a heating wire disposed inside the heat insulating cylinder. And the inspection window for inspecting the said heating wire from the outside was provided in the said heat insulation cylinder, It is characterized by the above-mentioned.

According to the semiconductor manufacturing apparatus of the present invention, by confirming the heating wire from the outside of the heat insulating cylinder through the inspection window, it is possible to easily know the deterioration status of the heating wire from the state of bending or distortion of the heating wire.
Therefore, it is possible to know the replacement timing of the heating wire from the state of deterioration of the heating wire before a problem such as disconnection due to the deterioration occurs. As a result, it is possible to reduce a possibility that a defect such as disconnection of the heating wire occurs during the heat treatment of the substrate to be processed, causing a defect in the substrate to be processed.

In this semiconductor manufacturing apparatus, the heating wire is spirally disposed along the inside of the heat insulating cylinder, and the semiconductor manufacturing device places the substrate to be processed outside the spiral heating wire. An inner tube that can be in an isolated state may be provided.

According to this semiconductor manufacturing apparatus, even if the semiconductor manufacturing apparatus has an inner tube inside the heating wire and it is difficult to confirm the heating wire from the inside of the heat insulating cylinder, the heating wire is not bent or distorted. From the situation, it is possible to easily know the condition of the heating wire deterioration.

In this semiconductor manufacturing apparatus, the inspection window is preferably formed of quartz glass.
According to this semiconductor manufacturing apparatus, since the inspection window is made of quartz glass having a low thermal conductivity, it is possible to reduce the amount of heat released inside the heat insulating cylinder through the inspection window. In addition, since quartz glass has a very small coefficient of thermal expansion, the heat insulating window can be provided in the heat insulating cylinder relatively easily without being affected by temperature change or temperature difference.

In this semiconductor manufacturing apparatus, it is preferable that the inspection window is provided with a reference scale corresponding to the position of the unused heating wire that passes through the inspection window.
According to this semiconductor manufacturing apparatus, the reference scale attached to the inspection window can be compared with the distortion or deflection of the heating wire in use, so that the degree of deterioration of the heating wire can be easily known from the comparison. it can.

In this semiconductor manufacturing apparatus, it is more preferable that the inspection window is provided with a replacement instruction scale indicating the replacement timing of the heating wire so that the inspection window can be compared with the heating wire transmitted through the inspection window.
According to this semiconductor manufacturing apparatus, it is possible to easily determine whether the heating wire has deteriorated and is in the replacement period by comparing the replacement indication scale attached to the inspection window with the distortion or deflection of the heating wire in use. You can understand. As a result, it is possible to know the replacement timing of the heating wire before problems such as cutting due to deterioration of the heating wire occur.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments embodying the present invention will be described with reference to FIGS.
FIG. 1 is a cross-sectional view showing a cross-sectional structure of a vertical diffusion furnace 1 as a semiconductor manufacturing apparatus.
As shown in FIG. 1, the vertical diffusion furnace 1 is a device for heat-treating a substrate to be processed, and has a housing 10. Inside the housing 10, there are a cylindrical heater 11 and an inner tube 12 that is concentric with the cylindrical heater 11 provided inside the cylindrical heater 11. A boat 13 on which a plurality of substrates to be processed (workpieces) W are mounted is disposed inside the inner tube 12.

The housing 10 has a door (not shown) used for maintenance and the like. When the door is opened, the outer surface 11A of the cylindrical heater 11 disposed inside the housing 10 is exposed from the outside of the housing 10. You can see it.

A heater support portion 10A is formed to extend on the inner side surface of the housing 10, and the heater support portion 10A.
A hole 10 </ b> B having a size substantially the same as the outer diameter of the inner tube 12 is formed through. The heater support portion 10A is provided between the top plate 10C of the housing 10 so that the cylindrical heater 11 can be disposed, and the upper surface of the heater support portion 10A is configured to be substantially horizontal. .

An annular heater base 14 having substantially the same size as the bottom surface of the cylindrical heater 11 is fixed on the upper surface of the heater support portion 10A. The bottom surface of the cylindrical heater 11 is supported and fixed on the upper surface of the heater base 14. Further, a heat insulating material 14 </ b> A that covers the upper surface opening of the cylindrical heater 11 is fixed to the upper surface of the cylindrical heater 11.

An annular furnace port flange 15 is fitted and fixed to the inner peripheral surface of a hole 10B formed through the heater support 10A.
The upper portion of the furnace port flange 15 extends upward from the upper surface of the heater support portion 10 </ b> A, and is formed in an annular shape having substantially the same size as the diameter of the inner tube 12. The bottom of the inner tube 12 is airtightly fixed to the top of the furnace port flange 15. Further, the inner diameter of the furnace port flange 15 is formed to be approximately the same as the inner diameter of the inner tube 12.

A boat 13 is detachably disposed in the inner tube 12 (processing chamber 12A). The boat 13 is configured to mount a plurality of workpieces W between a top plate 13B and a bottom plate 13C supported by the frame 13A.

The boat 13 is mounted and fixed to the seal cap 16 via a heat insulating cap 17.
The upper surface of the heat insulating cap 17 is configured to detachably mount and fix the bottom plate 13C of the boat 13. The lower surface of the heat insulating cap 17 is fixed to the seal cap 16.

The seal cap 16 is formed in such a size that the lower part of the furnace port flange 15 can be covered in a lid shape from below, and is moved up and down by a lifting device (not shown) so as to move the furnace port flange 1.
It is comprised so that contact / separation is possible with respect to the lower part of 5. FIG. The peripheral portion of the upper surface of the seal cap 16 is in contact with the lower portion of the furnace port flange 15, and when it comes into contact with the lower surface of the furnace port flange 15, the space between the furnace port flange 15 is hermetically sealed. That is, the inside of the inner tube 12 (the processing chamber 12A) is hermetically sealed from the outside when the seal cap 16 comes into contact with the furnace port flange 15.

That is, the boat 13 is placed and fixed on the upper surface of the heat insulating cap 17 when the seal cap 16 moves down most, and is inserted into the inner tube 12 by the upward movement of the seal cap 16 and hermetically sealed in the processing chamber 12A. It has come to be. Further, the boat 13 is detached from the inner tube 12 by the downward movement of the seal cap 16 from the state hermetically sealed in the processing chamber 12A, and is removed from the upper surface of the heat insulating cap 17 when the seal cap 16 is moved down most. Be able to.

A gas introduction pipe 18 and an exhaust pipe 19 from the outside of the inner pipe 12 are communicated with the processing chamber 12A. The gas introduction pipe 18 communicates from the outside of the furnace port flange 15 to the upper part of the processing chamber 12A. The exhaust pipe 19 communicates with the outside of the furnace port flange 15 from the processing chamber 12A.

With the above configuration, the vertical diffusion furnace 1 transfers each workpiece W mounted on the boat 13 to the processing chamber 12A.
And heat-treated with the cylindrical heater 11. The vertical diffusion furnace 1 introduces gas from the gas introduction pipe 18 into the sealed processing chamber 12A and exhausts the gas in the processing chamber 12A to the exhaust pipe 1.
9 can be discharged.

As shown in FIGS. 2 and 3, the cylindrical heater 11 includes a cylindrical heat insulating layer 21 made of a heat insulating material.
have. On the inner surface of the heat insulating layer 21, a plurality of heating wire holding members 22 extending in the vertical direction on the inner surface are arranged and fixed at equal angular intervals. A plurality of holding holes 23 are formed through the heating wire holding member 22 at predetermined intervals in the vertical direction.

The cylindrical heater 11 is divided into four blocks that are continuous in the vertical direction, and an L (Lower) block 20A and a CL (Center Lower) block 20B are sequentially arranged from the bottom.
, A CU (Center Upper) block 20C and a U (Upper) block 20D. That is, the L block 20A is assigned to the lowermost part of the cylindrical heater 11, and the CL block 20B is assigned to the lower center of the cylindrical heater 11 adjacent to the upper side of the L block 20A. Further, the CU block 20C is composed of the CL block 2
Assigned to the upper center of the cylindrical heater 11 adjacent to the upper side of 0B,
D is assigned to the uppermost part of the cylindrical heater 11 adjacent to the upper side of the CU block 20C.

On the inner side surface of the L block 20 </ b> A, a single lower heating wire 24 </ b> A is spirally arranged by inserting each holding hole 23 formed in the heating wire holding member 22. Lower heating wire 24A
Is arranged between the lower part and the upper part of the L block 20A by inserting and holding the holding holes 23 of the heating wire holding members 22 in a predetermined order.

The upper end and the lower end of the lower heating wire 24A are electrically connected to the base ends of separate terminals 25A, respectively. Each terminal 25A has a heat insulating layer 2 at the upper and lower portions of the L block 20A, respectively.
1 and the end of each terminal 25 </ b> A is extended to the outside of the heat insulating layer 21. That is, power can be supplied from the outside to each terminal 25A.
When electric power is supplied between them, electric power is supplied to the lower heating wire 24A, and the electric heating wire 24 is supplied by the electric power.
A generates heat.

The L block 20A is provided with a first temperature sensor 26A and a second temperature sensor 27A. Each temperature sensor 26A, 27A is formed in a bar shape,
A thermocouple for measuring the temperature is provided at each tip. And each temperature sensor 26A, 27A is penetrated and supported from the outside of the cylindrical heater 11 to the inside of the cylindrical heater 11,
Each tip portion is arranged in the vicinity of the inner tube 12 so that the temperature in the vicinity of the inner tube 12 can be measured. The second temperature sensor 27A shuts off the power supplied between the terminals 25A and forcibly cuts the power supply to the lower heating wire 24A when the measured temperature is equal to or higher than a predetermined temperature. It has become.

On the inner surface of the CL block 20B, one central lower heating wire 24B is provided with a heating wire holding member 22.
Each of the holding holes 23 formed in is inserted into a spiral shape. The central lower heating wire 24B is disposed between the lower portion and the upper portion of the CL block 20B by inserting and holding the holding holes 23 of the heating wire holding members 22 in a predetermined order.

The upper end and the lower end of the central lower heating wire 24B are electrically connected to the base ends of separate terminals 25B, respectively. Each terminal 25B is penetrated and supported by the heat insulating layer 21 at the upper part and the lower part of the CL block 20B, and the tip of each terminal 25B is extended to the outside of the heat insulating layer 21. That is, power can be supplied from the outside to each terminal 25B. When power is supplied between the terminals 25B, power is supplied to the central lower heating wire 24B, and the power heating wire 24B is supplied by the power. It is supposed to generate heat.

The CL block 20B is provided with a first temperature sensor 26B and a second temperature sensor 27B. Each of the temperature sensors 26B and 27B is formed in a bar shape, and a thermocouple for measuring the temperature is provided at each tip. And each temperature sensor 26B, 27B is penetrated and supported from the exterior of the cylindrical heater 11 to the inside of the cylindrical heater 11, and each tip part is arrange | positioned in the vicinity of the inner tube 12, and the temperature of the vicinity of the inner tube 12 is provided. Can be measured. The second temperature sensor 27B cuts off the power supplied between the terminals 25B and forcibly cuts off the power supply to the central lower heating wire 24B when the measured temperature becomes a predetermined temperature or higher. It is like that.

On the inner surface of the CU block 20C, one central upper heating wire 24C is connected to the heating wire holding member 22.
Each of the holding holes 23 formed in is inserted into a spiral shape. The central upper heating wire 24C is disposed between the lower part and the upper part of the CU block 20C by inserting and holding the holding holes 23 of the heating wire holding members 22 in a predetermined order.

The upper end and the lower end of the central upper heating wire 24C are electrically connected to the base ends of separate terminals 25C, respectively. Each terminal 25C is penetrated and supported by the heat insulating layer 21 at the upper and lower portions of the CU block 20C, and the tip of each terminal 25C is extended to the outside of the heat insulating layer 21. That is, power can be supplied to each terminal 25C from the outside. When power is supplied between the terminals 25C, power is supplied to the central upper heating wire 24C, and the electric heating wire 24C is supplied by the power. It is supposed to generate heat.

The CU block 20C is provided with a first temperature sensor 26C and a second temperature sensor 27C. Each of the temperature sensors 26C and 27C is formed in a rod shape, and a thermocouple for measuring the temperature is provided at each tip portion. And each temperature sensor 26C, 27C is penetrated and supported from the outside of the cylindrical heater 11 to the inside of the cylindrical heater 11, and the temperature of the vicinity of the inner tube 12 is set by arranging the respective tip portions in the vicinity of the inner tube 12. Can be measured. The second temperature sensor 27C shuts off the power supplied between the terminals 25C and forcibly cuts the power supply to the central upper heating wire 24C when the measured temperature is equal to or higher than a predetermined temperature. It is like that.

On the inner side surface of the U block 20 </ b> D, a single upper heating wire 24 </ b> D is spirally arranged by passing through each holding hole 23 formed in the heating wire holding member 22. Upper heating wire 24D
Are arranged between the lower part and the upper part of the U block 20D by inserting and holding the holding holes 23 of the heating wire holding members 22 in a predetermined order.

The upper end and the lower end of the upper heating wire 24D are electrically connected to the base ends of separate terminals 25D, respectively. Each terminal 25D has a heat insulating layer 2 at the upper and lower portions of the U block 20D, respectively.
1 and the end of each terminal 25 </ b> D is extended to the outside of the heat insulating layer 21. That is, power can be supplied from the outside to each terminal 25D.
When electric power is supplied between them, electric power is supplied to the upper heating wire 24D, and the electric heating wire 24 is supplied by the electric power.
D generates heat.

The U block 20D is provided with a first temperature sensor 26D and a second temperature sensor 27D. Each temperature sensor 26D, 27D is formed in a bar shape,
A thermocouple for measuring the temperature is provided at each tip. And each temperature sensor 26D, 27D is penetrated and supported from the outside of the cylindrical heater 11 to the inside of the cylindrical heater 11,
Each tip portion is arranged in the vicinity of the inner tube 12 so that the temperature in the vicinity of the inner tube 12 can be measured. The second temperature sensor 27D shuts off the power supplied between the terminals 25D and forcibly cuts off the power supply to the upper heating wire 24D when the measured temperature is equal to or higher than a predetermined temperature. It has become.

In the present embodiment, each of the heating wires 24A, 24B, 24C, and 24D is a heating wire that generates heat when supplied with electric power, for example, a nichrome wire, and is formed in an electric wire shape having a thickness of 20 mm.

As shown in FIG. 3, a heating wire inspection window 28 is provided in the U block 20 </ b> D of the cylindrical heater 11. The heating wire inspection window 28 is made of light-transmitting quartz glass, and is fitted and fixed to a rectangular window frame formed through the heat insulating layer 21. That is, the heating wire inspection window 28 enables the heating wire 24 </ b> D disposed along the inner surface of the heat insulating layer 21 to be inspected from the outside of the cylindrical heater 11 while being held by the heating wire holding member 22. Further, the heating wire inspection window 28 is provided at a substantially intermediate position between the two adjacent heating wire holding members 22. In the present embodiment, only one heating wire inspection window 28 is provided in the cylindrical heater 11.

By the way, the upper heating wire 24D supported by the heating wire holding member 22 is shown in FIG.
), The state of arrangement between the heating wire holding members 22 changes depending on the state of deterioration. For example, the upper heating wire 24D is arranged in a straight line in the horizontal direction while being supported by the heating wire holding member 22, as shown in FIG. Is done. On the other hand, if the upper heating wire 24D is distorted or bent due to deterioration, as shown in FIG. 4 (b), the upper heating wire 24D is in a state of being curved and sagging in a portion other than the portion supported by the heating wire holding member 22. There are also cases where it is arranged in a case, or it is broken and broken.
The deterioration of the upper heating wire 24D is considered to be caused by metal fatigue caused by repeated thermal expansion of the heating wire 24D.

And the malfunction of the upper heating wire 24D due to bending may cause a short circuit due to contact with the adjacent upper heating wire 24D, or heat generation unevenness. Also, the upper heating wire 24D due to disconnection
This problem makes it difficult to stop the heat generation of the upper heating wire 24D and bring the processing chamber 12A to a target high temperature. In particular, if the upper heating wire 24D is disconnected during the heat treatment of the workpiece W, the temperature of the processing chamber 12A is likely to decrease and the workpiece W during the heating treatment is likely to be defective. Therefore, before the upper heating wire 24D is disconnected. In addition, it is necessary to replace the upper heating wire 24D with a new one.

Therefore, in the present embodiment, the extension or deflection of the upper heating wire 24D is inspected through the heating wire inspection window 28, and the deterioration or replacement time of the upper heating wire 24D can be determined based on the inspection.

The lower heating wire 24A, the central lower heating wire 24B, and the central upper heating wire 24C also have problems due to deterioration and deterioration. However, the problems due to the deterioration and deterioration also occur due to the deterioration and deterioration of the upper heating wire 24D. Since it is the same as that, its description is omitted.

As shown in FIG. 5, the heating wire inspection window 28 is provided with a plurality of reference scales 30A, 30B, 30C and a plurality of replacement instruction scales 31A, 31B, 31C. 5 (a) shows a state of being visible from the heating wire inspection window 28 of the upper heating wire 24D that is not deteriorated, such as a new article, and FIG. 5 (b) is a view from the heating wire inspection window 28 of the upper heating wire 24D that is slightly deteriorated. FIG. 5 (c) shows the state that can be seen from the heating wire inspection window 28 of the upper heating wire 24 </ b> D that has deteriorated to an extent that requires replacement.

As shown in FIG. 5A, the reference scale 30A is attached to the heating wire inspection window 28 so as to be substantially parallel to the upper heating wire 24D without deterioration and to indicate a position below the upper heating wire 24D. ing. A corresponding replacement instruction scale 31A is provided below the reference scale 30A.

The replacement instruction scale 31A is attached to a position where the upper heating wire 24D whose lower side is the reference scale 30A deteriorates to a level that requires replacement and is distorted or bent to reach the lower side. . In other words, the lower side of the upper heating wire 24D that has reached the replacement time due to deterioration has reached the replacement instruction scale 31A. It should be noted that the upper heating wire 24 deteriorated so as to be replaced.
The position reached by the lower side of D is a position obtained in advance by a test or the like.

The reference scales 30B and 30C are the same scales as the above-described reference scales 30A, and the replacement instruction scales 31B and 31C respectively provided corresponding to the reference scales 30B and 30C are the above-described replacement instruction scales 31A. Since it is the same scale as, its explanation is omitted.

More specifically, for example, the upper heating wire 24D that is not distorted or bent like a new article is shown in FIG.
As shown in FIG. 4, the lower side is made to coincide with the reference scales 30A, 30B, 30C.
On the other hand, as shown in FIG. 5B, the upper heating wire 24D that has deteriorated due to use and has been stretched or bent is displaced from the reference scales 30A, 30B, and 30C. At this time, the lower side of the upper heating wire 24D particularly shows a case where the upper heating wire 24D is largely deviated from the reference scale 30B.

Furthermore, as shown in FIG. 5C, the upper heating wire 24D deteriorated due to use is further shifted from the reference scales 30A, 30B, 30C on the lower side. At this time, the lower side of the upper heating wire 24D is particularly greatly displaced with respect to the reference scale 30B, and shows a case where the upper heating wire 24D has moved to a position overlapping the replacement instruction scale 31B.

The upper heating wire 24D whose lower side has moved to the exchange instruction scale 31B is adjacent to the upper heating wire 24D.
There is a high risk of contact with D. Further, the upper heating wire 24D in the vicinity of the replacement instruction scale 31B is greatly stretched and bent, and there is a high possibility that a large crack has occurred or that metal fatigue has progressed. Therefore, if the use of the upper heating wire 24D is continued, there is a very high possibility that the upper heating wire 24D is defective. That is, it can be seen that the upper heating wire 24D whose lower side has moved to the replacement instruction scale 31B is in the replacement period.

With the above configuration, the replacement time due to the deterioration of the upper heating wire 24D is set so that the heating wire inspection window 28 and the replacement indication scales 31A, 31B, and 31C before the disconnection occurs.
It can be easily known.

Next, effects of the present embodiment configured as described above will be described below.
(1) According to the present embodiment, the heating wire inspection window 28 is provided in the heat insulating layer 21. Therefore, normally, the upper heating wire 24D which is disposed between the heat insulating layer 21 and the inner tube 12 and cannot be easily confirmed from the outside or the inside of the cylindrical heater 11 is very easily confirmed from the outside. I was able to do it. As a result, it is possible to know the replacement timing of the upper heating wire 24D from the state of deterioration that appears as bending or distortion in the upper heating wire 24D, and problems such as disconnection occur in the upper heating wire 24D during the heat treatment of the workpiece W. The possibility that defects may occur in the workpiece W can be reduced.

(2) According to this embodiment, the heating wire inspection window 28 is made of quartz glass. Accordingly, since quartz glass has a low thermal conductivity, heat released to the outside from the cylindrical heater 11 through the heating wire inspection window 28 can be reduced. Also, quartz glass has a very low coefficient of thermal expansion,
The heating wire inspection window 28 can be suitably provided in the heat insulating layer 21 which is not easily affected by temperature change or temperature difference.

(3) According to the present embodiment, the reference scales 30A, 30B, and 30C corresponding to the upper heating wire 24D are provided in the heating wire inspection window 28. Therefore, the elongation and deflection generated in the upper heating wire 24D due to deterioration can be easily compared with the case of the unused upper heating wire 24D.

Further, replacement instruction scales 31A, 31B, and 31C are provided in the heating wire inspection window 28 so that it can be easily determined whether or not the upper heating wire 24D is in the replacement period with reference to the replacement instruction scales 31A, 31B, and 31C. . As a result, it is possible to know the replacement timing of the upper heating wire 24D before the failure due to the deterioration of the upper heating wire 24D, particularly before the cutting occurs.

(4) According to the present embodiment, the heating wire inspection window 28 is provided in the U block 20D. Therefore,
By confirming the state of the upper heating wire 24D having the highest load due to heat, each of the other heating wires 24A
, 24B, 24C can also be known. As a result, all the heating wires 24A, 24B, 24 constituting the cylindrical heater 11 can be obtained simply by providing the heating wire inspection window 28 in the U block 20D.
It is possible to know the replacement time of C and 24D.

In addition, you may change the said embodiment as follows.
In the above embodiment, the inner tube 12 is provided between the tubular heater 11 and the boat 13, but the present invention is not limited to this as long as the tubular heater 11 can raise the boat 13 to a high temperature. For example, between the cylindrical heater 11 and the boat 13, in addition to the inner pipe 12, other pipes and cylinders may be provided, or the inner pipe 12 may not be provided.

In the above embodiment, the cylindrical heater 11 is divided into four blocks in the vertical direction, but may be divided into other than four blocks. Moreover, the cylindrical heater 11 does not need to be divided.

In the above embodiment, each heating wire 24A, 24B, 24C, 24D has an electric wire shape with a thickness of 20 mm, but the thickness of the heating wire is not limited to this.
In the above embodiment, the heating wire inspection window 28 is formed of quartz glass having light transmittance, but may be formed of other materials having light transmittance and heat resistance.

In the above embodiment, one heating wire inspection window 28 is provided in the U block 20D, but the heating wire inspection window 28 may also be provided in each of the other blocks 20A, 20B, and 20C. U
A plurality of heating wire inspection windows 28 may be provided in the block 20D. By providing a plurality of heating wire inspection windows 28, the state of deterioration of each heating wire 24A, 24B, 24C, 24D, that is, the replacement time can be known more accurately.

In the above embodiment, the heating wire inspection window 28 is crossed by the upper heating wire 24D three times, but the number of times the upper heating wire 24D crosses the heating wire inspection window 28 is not limited thereto.
In the above embodiment, the deterioration determination of each heating wire 24A, 24B, 24C, 24D of the vertical diffusion furnace 1 is performed, but the deterioration determination of the heating wire is performed by another semiconductor manufacturing apparatus using the heating wire, for example, horizontal diffusion. You may use for a furnace, a thermostat, a washing tank, a drying furnace, or a burn-in furnace.

Sectional drawing which shows the cross-section of the semiconductor manufacturing apparatus in this embodiment. Sectional drawing which shows the cross-section of the cylindrical heater of the semiconductor manufacturing apparatus in this embodiment. The perspective view which shows the perspective structure which made a cross section the part of the cylindrical heater of the semiconductor manufacturing apparatus in this embodiment. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing explaining the heating wire of the semiconductor manufacturing apparatus in this embodiment, Comprising: (a) is a figure which shows the state of a new heating wire, (b) is the state of the heating wire which became deterioration and advanced and it became replacement | exchange time. FIG. It is explanatory drawing explaining the state of the heating wire which can be confirmed from the heating wire inspection window of the semiconductor manufacturing apparatus in this embodiment, Comprising: (a) is a figure which shows the state of a new heating wire, (b) is the deteriorated heating wire. The figure which shows the state of this, (c) is a figure which shows the state of the heating wire which became deterioration and progressed.

Explanation of symbols

W ... Substrate (workpiece), 1 ... Vertical diffusion furnace, 10 ... Housing, 10A ... Heater support, 1
0B ... hole, 10C ... top plate, 11 ... cylindrical heater, 11A ... outer side, 12 ... inner tube, 12A ... processing chamber, 13 ... boat, 13A ... frame, 13B ... top plate, 13C ... bottom plate, 14 ... heater Base, 14A ... heat insulating material, 15 ... furnace port flange, 16 ... seal cap, 17 ... heat insulating cap, 18 ... gas introduction pipe, 19 ... exhaust pipe, 20A ... L block, 20B ... CL block, 20
C ... CU block, 20D ... U block, 21 ... heat insulation layer, 22 ... heating wire holding member, 23 ...
Holding hole, 24A ... lower heating wire, 24B ... center lower heating wire, 24C ... center upper heating wire, 24
D: Upper heating wire, 25A, 25B, 25C, 25D ... Terminal, 26A, 26B, 26C, 2
6D ... 1st temperature sensor, 27A, 27B, 27C, 27D ... 2nd temperature sensor, 28 ... Heating wire inspection window, 30A, 30B, 30C ... Reference | standard scale, 31A, 31B, 31C ... Replacement instruction | indication scale.

Claims (5)

A substrate to be processed disposed inside the heat insulation tube by a heating wire disposed inside the heat insulation tube,
A semiconductor manufacturing apparatus for performing a heat treatment at a target temperature by heating the heating wire,
A semiconductor manufacturing apparatus, wherein an inspection window for inspecting the heating wire from the outside is provided in the heat insulating cylinder. The semiconductor manufacturing apparatus according to claim 1,
The heating wire is arranged in a spiral along the inside of the heat insulating cylinder,
The semiconductor manufacturing apparatus includes an inner tube capable of keeping a substrate to be processed isolated from outside air inside the spiral heating wire. In the semiconductor manufacturing apparatus according to claim 1 or 2,
The semiconductor manufacturing apparatus, wherein the inspection window is made of quartz glass. In the semiconductor manufacturing apparatus according to any one of claims 1 to 3,
The semiconductor manufacturing apparatus according to claim 1, wherein a reference scale corresponding to a position of the unused heating wire that is transmitted through the inspection window is attached to the inspection window. In the semiconductor manufacturing apparatus according to any one of claims 1 to 4,
The semiconductor manufacturing apparatus according to claim 1, wherein the inspection window is provided with a replacement instruction scale indicating a replacement timing of the heating wire so as to be compared with the heating wire transmitted through the inspection window.

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