KR20050086404A - Heat-treating apparatus - Google Patents

Abstract

A heat-treating apparatus comprising a reaction chamber accommodating an object to be treated, a heat-insulating body surrounding the reaction chamber, holes defined in the heat- insulating body, annular spacer members provided in the holes, and heater elements inserted in the annular spacer members.

Description

Heat treatment device {HEAT-TREATING APPARATUS}

The present invention relates to a fixing method and a heat treatment apparatus for a heater for a heat treatment apparatus used in a heat treatment apparatus for heat treating a target object, for example, a semiconductor wafer.

In the manufacturing process of a semiconductor device, the heat processing apparatus is used in order to perform various processes, such as a film-forming process and an oxidation process of a to-be-processed object, for example, a semiconductor wafer. The heat treatment apparatus includes a reaction chamber for accommodating a semiconductor wafer. A heating member having a heater and a heat insulator is provided to surround the reaction chamber. The reaction chamber is heated to a predetermined temperature by the heater, and various processes are performed on the semiconductor wafer.

As the heater of the heat treatment apparatus, for example, an elongated heater element formed by sealing a linear resistance heating element in a sealing member is used. In addition, the heat insulator is formed of stainless steel (SUS), for example. A plurality of holes are formed in the heat insulator. Then, the heater element is inserted into the hole of the heat insulator. The plurality of holes are arranged such that the heater elements have a predetermined distance from the reaction chamber.

As described above, in the conventional heat treatment apparatus, the heater element is directly inserted into the hole of the heat insulator. Therefore, there is a fear that contaminants such as metal powder (metal contaminants) may be generated by friction between the heater element and the inner wall of the hole of the heat insulator. When the heat treatment is performed in a state where such a contaminant is generated, the contaminant may adhere to the semiconductor wafer. In that case, the characteristics of the formed semiconductor device deteriorate and, as a result, the yield deteriorates. In fact, when the contaminant is a metal contaminant, the characteristics of the formed semiconductor device are significantly deteriorated. In addition, the heater element itself may be damaged by friction between the heater element and the inner wall of the hole of the heat insulator.

In addition, although a cable connected to a power source is connected to the end of the heater element, when a load is applied to the cable, for example, when the cable is entangled with another member, the heater element may be stretched by the cable and be damaged.

1 is a schematic diagram of a heat treatment apparatus of an embodiment of the present invention.

2 is a perspective view of a heat insulator of one embodiment of the present invention.

3 is a perspective view showing a state in which a heater element is inserted into a hole of an insulator of an embodiment of the present invention.

Fig. 4 is an enlarged view of the vicinity of the hole in the state where the heater element is inserted into the hole of the heat insulator of the embodiment of the present invention.

5 is a side view of a heater element of one embodiment of the present invention.

Fig. 6 is a side view showing a connection state of a heater element and a cable of one embodiment of the present invention.

7A is a perspective view of a first sub-heater of one embodiment of the present invention, and FIG. 7B is a side view of the first sub-heater of one embodiment of the present invention.

The present invention has been made in view of the above problems, and an object thereof is to provide a fixing method and a heat treatment apparatus for a heater for a heat treatment apparatus in which generation of contaminants is prevented.

In addition, an object of the present invention is to provide a fixing method and a heat treatment apparatus for a heater for a heat treatment apparatus that can prevent damage to the heater.

The present invention provides a reaction chamber for accommodating a target object, a heat insulator provided to surround the reaction chamber, a plurality of holes provided in the heat insulator, a plurality of annular spacer members respectively provided in the plurality of holes, And a plurality of heater elements respectively inserted in the plurality of annular spacer members.

According to the invention, a plurality of heater elements are fixed by a plurality of annular spacer members. This prevents friction between the heater element and the inner wall of the hole of the heat insulator, and no contaminants are generated. In addition, there is no risk of breakage of the heater element.

Preferably, the spacer member is elastic. For example, the spacer member is an O ring.

For example, the heater element has a straight portion. In this case, the tubular portion of the heater element is preferably arranged at predetermined intervals with respect to the reaction chamber.

In addition, the present invention is a reaction chamber for accommodating the object to be processed, a metal heat insulator provided to surround the reaction chamber, a plurality of holes provided in the heat insulator, and a plurality of heaters respectively inserted into the plurality of holes. And an inner wall of the plurality of holes is coated with ceramic.

According to the invention, the plurality of heater elements are in contact with the inner wall of the pores coated with ceramics and are not in contact with the metal part of the insulator. For this reason, metal contaminants (contaminants) are not generated and the risk of breakage of the heater element is also reduced.

Preferably, the ceramic is alumina, silica or yttria.

Preferably, the ceramic is porous. In this case, thermal shock resistance is improved.

Further, preferably, the surface of the reaction chamber side of the heat insulator is coated with ceramic. In this case, since the heater element is completely prevented from coming into contact with the metal surface of the heat insulator, the generation of metal contaminants is prevented and the risk that the heater element is broken is further reduced.

Further, preferably, the heater element is connected to a cable, and the cable is fixed to the device outer wall by a fixing member near the end of the heater element. In this case, there is little possibility that a heater element will be damaged even if a load is applied to a cable. Also in this case, the cables are aligned and difficult to entangle.

The fixing member is for example a tie wrap.

The present invention also provides a reaction chamber for accommodating a target object, a heat insulator provided to surround the reaction chamber, a plurality of holes provided in the heat insulator, and a plurality of annular spacer members respectively provided in the plurality of holes. And a method of assembling a heat treatment apparatus having a plurality of heater elements respectively inserted into the plurality of annular spacer members, the process of disposing a plurality of annular spacer members in the plurality of holes, respectively, And a step of inserting a plurality of heater elements into the annular spacer member, respectively.

According to the invention, a plurality of heater elements are fixed by a plurality of annular spacer members. This prevents friction between the heater element and the inner wall of the hole of the heat insulator, and no contaminants are generated. In addition, there is no risk of breakage of the heater element.

Preferably, the method further comprises a step of fixing the cable connected to the heater element to the device outer wall by a fixing member near the end of the heater element.

Alternatively, the method further comprises a step of fixing the cable connected to the heater element to the device outer wall by a tie wrap near the end of the heater element.

Hereinafter, the case where the batch type vertical processing apparatus shown in FIG. 1 is used for the fixing method and the heat processing apparatus of the heater for heat processing apparatuses which concern on embodiment of this invention is demonstrated to an example.

As shown in Fig. 1, the heat treatment apparatus 1 includes a substantially cylindrical reaction tube 2 whose longitudinal direction is directed in the vertical direction. The reaction tube 2 has a double tube structure composed of an inner tube 3 and an outer tube 4 covering the inner tube 3 and having a ceiling having a predetermined distance from the inner tube 3. The inner tube 3 and the outer tube 4 are formed of a heat insulating material, for example, quartz.

Below the external appearance 4, the manifold 5 which consists of stainless steel (SUS) formed cylindrically is arrange | positioned. The manifold 5 is hermetically connected to the lower end of the exterior 4. In addition, the inner tube 3 is supported by a support ring 6 which protrudes from the inner wall of the manifold 5 and is formed integrally with the manifold 5.

The lid 7 is disposed below the manifold 5. The cover 7 is comprised by the boat elevator 8 so that up-and-down movement is possible. And when the cover 7 is raised by the boat elevator 8, the lower side of the manifold 5 will close.

The cover 7 is formed with a rotating shaft 9 which passes through the cover 7 and rotates by the motor M. As shown in FIG. The turntable 10 which is rotatable is formed on the rotation shaft 9. On the turntable 10, a wafer boat 12 made of, for example, quartz is mounted via a heat insulating unit 11. In the wafer boat 12, a plurality of workpieces, for example, semiconductor wafers W, are housed at predetermined intervals in a vertical direction. Then, when the rotating shaft 9 is rotated by the motor M, the wafer boat 12 is rotated through the turntable 10 and the thermal insulation unit 11, that is, the semiconductor wafer W is rotated.

A plurality of process gas introduction pipes 13 penetrate the side wall of the manifold 5 (only one process gas introduction pipe 13 is shown in FIG. 1 for convenience of illustration). The process gas introduction pipe 13 extends to the inside of the inner pipe 3. For example, as shown in FIG. 1, the processing gas introduction pipe 13 penetrates through the side wall of the manifold 5 below the support ring 6 (downward of the inner pipe 3), and the processing gas introduction pipe. The tip of (13) is bent upward along the inner tube (3). Thereby, the process gas supplied from the gas supply source which is not shown in figure is introduce | transduced into the inner tube 3 through the process gas introduction tube 13.

In addition, an exhaust pipe 14 is connected to the side wall of the manifold 5. The exhaust pipe 14 is connected to the side wall of the manifold 5 above the support ring 6 and communicates with the space formed between the inner tube 3 and the outer tube 4 of the reaction tube 2. As a result, the exhaust gas in the reaction tube 2 is discharged out of the heat treatment apparatus 1 through the space between the inner tube 3 and the outer tube 4 and the exhaust pipe 14. The exhaust pipe 14 is connected to the exhaust unit which consists of a vacuum pump etc. which are not shown in figure. The exhaust unit can set the pressure in the reaction tube 2 to a predetermined pressure.

The heat insulator 15 which consists of stainless steel (SUS) is provided in the circumference | surroundings of the reaction tube 2 so that the reaction tube 2 may be enclosed. 2 shows a perspective view of the heat insulator 15. As shown in Fig. 2, the heat insulator 15 is composed of a cylindrical main body 15a, a ceiling plate 15b, and a bottom plate 15c. The diameter of the main body 15a is larger than the reaction tube 2. The ceiling plate 15b is a disk-shaped plate covering the upper part of the main body 15a. The bottom plate 15c is ring-shaped, and its inner circumferential wall is formed in a size corresponding to the outer circumferential wall of the reaction tube 2. Inside the main body 15a of the heat insulator 15, a coolant flow path (for example, a cooling water path) (not shown) is provided. Thereby, the temperature of the reaction tube 2 can be cooled by supplying cooling water to a cooling water path.

A plurality of holes 16a are formed in the ceiling plate 15b of the heat insulator 15. The holes 16a are formed at equal intervals, for example, at intervals of several mm, along the periphery thereof. In addition, a plurality of holes 17a are formed in the bottom plate 15c of the heat insulator 15 at positions corresponding to the plurality of holes 16a (vertical downward positions of the plurality of holes 16).

Then, as shown in Fig. 3, the heater element 18 is inserted vertically into the hole 16a and the hole 17a. That is, the heater element 18 is disposed through the ceiling plate 15b and the bottom plate 15c of the heat insulator 15. In addition, only some heater elements 18 are shown in FIG. 3 in order to make the state in which the heater elements 18 are inserted easier to understand. Such a plurality of heater elements 18 constitute a heater for the heat treatment apparatus.

In the present embodiment, a hole 16b into which the first sub heater described later is inserted is formed in the ceiling plate 15b, and a hole 17b into which the second sub heater described later is inserted is formed in the bottom plate 15c. have.

By the way, the O-ring 19 is arrange | positioned in each hole 16a, 17a. 4 shows a schematic view of the vicinity of the hole 16a with the heater element 18 inserted. As shown in FIG. 4, an O-ring 19 is disposed on the inner wall of the hole 16a, and a heater element 18 is inserted into the O-ring 19. As shown in FIG. As a result, the heater element 18 is firmly fixed to the inner wall of the hole 16a via the O-ring 19 so that there is no rattling in the hole 16a. Therefore, the heater element 18 and the inner wall of the hole 16a are not rubbed, and there is no fear of generating powder (pollutant). In addition, since the inner wall of the heater element 18 and the hole 16a is not rubbed, there is no fear that the heater element 18 will be broken. In addition, although the above was demonstrated about the hole 16a, it is the same also about the hole 17a.

In addition, the inner wall of the heat insulator 15 is coated with ceramic. Since the inner wall of the insulator 15 is coated with ceramic, the heater element 18 never comes into contact with the metal surface (stainless steel) of the insulator 15. As a result, metal contaminants are not generated. In addition, since the heater element 18 does not contact the metal surface of the heat insulator 15, the heater element 18 is more difficult to break. As the ceramic, for example, alumina, silica or yttria is used. This ceramic is made of porous (polar). If the ceramic is polar, thermal shock resistance is improved.

5 shows a schematic view of the heater element 18. As shown in FIG. 5, the heater element 18 is provided with the resistance heating body 18a and the sealing member 18b. The resistance heating element 18a is made of, for example, linear and flexible high purity carbon wire. This carbon wire is formed by weaving a plurality of bundles of carbon fibers that are, for example, carbon members having a line diameter of about 10 μm. The sealing member 18b is made of ceramic to seal the resistance heating element 18a. In this embodiment, the carbon wire is enclosed in a transparent quartz tube having an outer diameter of several tens of mm. Both ends of the resistance heating body 18a are connected to the electrode member 20. The sealing member 18b seals from the end of one electrode member 20 to the end of the other electrode member 20, whereby the resistance heating element 18a is sealed in the sealing member 18b.

The electrode member 20 is connected to an external cable 21. The cable 21 is connected to a power supply not shown. 6 shows a connection state of the heater element 18 and the cable 21. As shown in FIG. 6, the electrode member 20 connected to the heater element 18 is connected to the core line 21a of the cable 21. The electrode member 20 and the core wire 21a are connected by high temperature soldering or crimping, for example. Then, electric power is supplied from the power supply to the resistance heating element 18a via the cable 21 and the electrode member 20 to heat the heater element 18.

In addition, the cable 21 connected to the heater element 18 is fixed to the outer wall or the outer wall cover (not shown) by the fixing member 22 near the end of the heater element 18. As the fixing member 22, a tie wrap is used, for example. In this case, the cable 21 is fixed to the outer wall or the outer wall cover by being pinched by the tie wrap. In this way, the cable 21 is fixed to the outer wall or the outer wall cover by the fixing member 22 near the end of the heater element 18, so that if the cable 21 is caught by another member, the cable 21 is loaded on the cable 21. There is no fear that the heater element 18 may be broken even if it is applied. In addition, since the cable 21 is fixed near the end of the heater element 18, it is difficult to align and entangle.

In addition, as a power supply method from a power supply to the heater element 18, you may connect all the heater elements 18 in parallel or in series, and may supply electric power from a common power supply. Alternatively, the heater elements 18 may be divided into a plurality of groups, the heater elements 18 may be connected in series for each group, and the group of heater elements 18 in series may be connected in parallel with each other.

A planar first sub heater 23 is provided below the ceiling portion (ceiling plate 15b) of the heat insulator 15 so as to face the reaction tube 2. FIG. 7A shows a perspective view of the first sub heater 23, and FIG. 7B shows a side view of the first sub heater 23. As shown in Figs. 7A and 7B, the first sub heater 23 is formed by inserting the resistance heating element 23b into, for example, a disk-shaped body 23a made of quartz having a thickness of about 8 mm. The resistive heating element 23b is made of carbon wire, for example, similarly to the resistive heating element 18a described above. The quartz tube 24 is welded to two places of the peripheral part of the disk-shaped body 23a. The quartz tube 24 is connected to a power source (not shown) via the cable 25. The quartz tube 24 of the first sub heater 23 is inserted into the hole 16b provided in the heat insulator 15, and the first sub heater 23 attaches the support 26 to the ceiling of the heat insulator 15. Supported by

The second sub heater 27 is provided at the lower end portion (bottom plate 15c) of the heat insulator 15. The second sub heater 27 is a heater element that is shorter than the heater element 18 and is inserted into the hole 17b formed inside the hole 17a. An O-ring 19 is disposed in the hole 17b, and the second sub heater 27 is fixed by the O-ring 19. The second sub heater 27 is connected to a power source (not shown) via the cable 28. In addition, the cable 28 is fixed to the outer wall or the outer wall cover by the fixing member 22 near the end of the second sub heater 27.

Boat elevator 8, motor M, process gas introduction pipe 13, heater element 18 (cable 21), first sub heater 23 (cable 25), second sub heater ( 27) (cable 28) is connected with a control unit (not shown). The control unit is composed of a microprocessor, a process controller and the like to measure the temperature, pressure and the like of each part of the heat treatment apparatus 1, and output a control signal or the like to each of the parts based on the measurement data to control.

Next, the heat processing using the heat processing apparatus 1 comprised as mentioned above is demonstrated easily. First, a predetermined number of semiconductor wafers W are accommodated in the wafer boat 12 in a state where the lid 7 is lowered by the boat elevator 8. Next, the semiconductor wafer W is loaded into the reaction tube 2 (inner tube 3) by raising the boat elevator 8. Subsequently, the temperature in the reaction tube 2 is raised to a predetermined temperature by the heater element 18, the first sub heater 23, and the second sub heater 27, and is connected to the exhaust pipe 14. The pressure in the reaction tube 2 is set to a predetermined pressure by the exhaust unit which does not.

When the inside of the reaction tube 2 is stabilized at a predetermined pressure and temperature, the processing gas is supplied from the processing gas supply pipe 13 to perform a predetermined heat treatment. In addition, the wafer boat 12 is rotated by the motor M during the heat treatment. After the heat treatment, the temperature in the reaction tube 2 is lowered to a predetermined temperature, and the pressure in the reaction tube 2 is returned to the normal pressure so that the wafer boat 12 (semiconductor wafer W) is removed from the reaction tube 2. Unloaded.

As described above, according to the present embodiment, the O-ring 19 is disposed on the inner wall of the hole 16a and the hole 17a (and the hole 16b and the hole 17b), and the heater is disposed in the O-ring 19. Since the element 18 (second sub-heater 27) is inserted, the heater element 18 (second sub-heater 27) is firmly fixed so that the hole 16a, the hole 17a (and the hole ( 16b), there is no rattling in the hole 17b]. Therefore, the heater element 18 (second sub heater 27) and the inner wall of the hole 16a and the hole 17a (and the hole 16b and the hole 17b) are not rubbed, and powder (contamination) Substance) is eliminated. In addition, there is no fear that the heater element 18 (second sub-heater 27) is broken.

According to this embodiment, since the cable 21 (cable 28) is fixed to the outer wall or the outer wall cover by the fixing member 22 near the end of the heater element 18 (the second sub heater 27). There is no risk that the heater element 18 (second sub-heater 27) is broken. In addition, the cables 21 (cables 28) are aligned and difficult to entangle.

According to this embodiment, since the inner wall of the heat insulator 15 is coated with ceramic, the heater element 18 never comes into contact with the metal surface of the heat insulator 15. As a result, metal contaminants are not generated. In addition, since the heater element 18 does not contact the metal surface of the heat insulator 15, the heater element 18 is more difficult to break. In addition, since the porous material is used for the ceramic, the thermal shock resistance of the heat insulator 15 is improved.

In addition, according to this embodiment, since the 1st sub heater 23 and the 2nd sub heater 27 are arrange | positioned at the upper part and the lower part of the reaction tube 2, the temperature in the reaction tube 2 can be made uniform. have.

In addition, this invention is not limited to said embodiment, A various deformation | transformation and an application are possible. Hereinafter, other embodiment applicable to this invention is described.

In the above embodiment, the O-ring 19 is disposed on the inner wall of the hole 16a and the hole 17a. However, if the O-ring 19 is disposed on at least one of the inner wall of the hole 16a and the hole 17a. do. If the O-ring 19 is disposed on at least one side, the heater element 18 is firmly fixed so that the heater element 18 does not rattle in the hole.

Or in the said embodiment, although the O-ring 19 is arrange | positioned in the inner wall of the hole 16a and the hole 17a, instead of arrange | positioning the O-ring 19 in the inner wall of the hole 16a and the hole 17a. The inner walls of the holes 16a and 17a may be coated with ceramic. In this case, even if the heater element 18 and the inner wall of the hole 16a and the hole 17a are rubbed, the heater element 18 does not come into contact with the metal surface of the heat insulator 15, thereby preventing the occurrence of metal contaminants. can do.

In the above embodiment, a tubular heater element 18 penetrating through the hole 16a and the hole 17a is used, but the heater element may be a U-shaped tube. In this case, for example, the U-tubular heater element is attached to the heat treatment apparatus 1 by being inserted into two adjacent holes 16a. In addition, the area to be heated is divided up and down, the heater element 18 inserted into the hole 16a heats the upper region, and the heater element 18 into which the hole 17a is inserted heats the lower region. You may comprise so that.

In the above embodiment, the resistance heating element 18a of the heater element 18 is made of carbon wire, but the resistance heating element 18a may be a linear and flexible high purity resistance heating element other than the carbon wire.

Although the said embodiment is a batch type heat processing apparatus whose reaction tube 2 is the double tube structure which consists of the inner tube 3 and the exterior 4, it is possible to apply this invention also to the heat treatment apparatus of a single tube structure. In addition, the to-be-processed object is not limited to the semiconductor wafer W, For example, it can be applied also to the glass substrate for LCDs.

Claims (14)

A reaction chamber for accommodating a target object, An insulator installed to surround the reaction chamber, A plurality of holes provided in the heat insulator, A plurality of annular spacer members respectively provided in the plurality of holes; And a plurality of heater elements respectively inserted in the plurality of annular spacer members. The heat treatment apparatus according to claim 1, wherein the spacer member has elasticity. 3. The heat treatment apparatus of claim 2, wherein the spacer member is an O-ring. The heat treatment apparatus according to any one of claims 1 to 3, wherein the heater element has a straight portion. The heat treatment apparatus according to claim 4, wherein the tubular portions of the heater elements are arranged at predetermined intervals with respect to the reaction chamber. A reaction chamber for accommodating a target object, A metal insulator installed to surround the reaction chamber; A plurality of holes provided in the heat insulator, A plurality of heater elements respectively inserted in the plurality of holes, And the inner walls of the plurality of holes are coated with ceramic. 7. The apparatus of claim 6, wherein the ceramic is alumina, silica or yttria. 8. The heat treatment apparatus according to claim 6 or 7, wherein the ceramic is porous. The heat treatment apparatus according to any one of claims 1 to 8, wherein the surface of the reaction chamber side of the heat insulator is coated with ceramic. 10. The heater element according to any one of the preceding claims, wherein the heater element is connected to a cable, And the cable is fixed to the device outer wall by a fixing member near an end of the heater element. The apparatus of claim 10, wherein the fixing member is a tie wrap. A reaction chamber for accommodating a target object, An insulator installed to surround the reaction chamber, A plurality of holes provided in the heat insulator, A plurality of annular spacer members respectively provided in the plurality of holes; A method of assembling a heat treatment apparatus having a plurality of heater elements respectively inserted in the plurality of annular spacer members, Disposing a plurality of annular spacer members, respectively, in the plurality of holes; And inserting a plurality of heater elements into the plurality of annular spacer members, respectively. The method according to claim 12, further comprising a step of fixing the cable connected to the heater element to the device outer wall by a fixing member near the end of the heater element. The method according to claim 13, further comprising the step of securing a cable connected to said heater element to a device outer wall by a tiewrap near the end of said heater element.