JP2001144023A - Vertical heat treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce heat release and to improve zone heating efficiency or controllability. SOLUTION: Concerning the vertical heat treatment device, a cylindrical heater 4 divided into plural zones and capable of heating control is installed in the direction of the height around a treatment vessel 3 housing a lot of objects (w) to be treated in the state of locating and supporting them in the direction of the height, and a metal contamination-proof pipe 5 is arranged between this heater 4 and the treatment vessel 3. A low heat conduction member 13 is interposed in the portion of the metal contamination-proof pipe 5 corresponding to a zone boundary Zx of the heater 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a vertical heat treatment apparatus.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, a semiconductor manufacturing apparatus for performing processes such as oxidation, diffusion, annealing, and CVD on an object to be processed, for example, a semiconductor wafer, is, for example, a batch capable of processing a large number of semiconductor wafers at one time. A vertical heat treatment apparatus is used. In this vertical heat treatment apparatus, generally, as shown in FIG. 4, a reaction tube (processing vessel) 3 for accommodating a large number of semiconductor wafers w arranged and supported at predetermined intervals in a height direction, and The heat treatment furnace 1 is constituted by a cylindrical heater 4 installed around the reaction tube 3 and a metal contamination prevention tube 5 arranged between the heater 4 and the reaction tube 3.

In FIG. 4, reference numeral 6 denotes a base plate on which the heater 4 is installed, 9 denotes a lid for opening and closing the lower end opening of the reaction tube, 10 denotes a heat insulating cylinder mounted on the lid 9, 2
Is a boat mounted on the heat retaining cylinder 10 and arranged to support a large number of semiconductor wafers w. In a low-temperature furnace or a CVD furnace, the metal contamination prevention tube 5 may not be provided. In the heater 4 of such a vertical heat treatment apparatus, the resistance heating element 12 is divided into a plurality of zones Z1 to Z5 in the height direction to enable uniform heat treatment between the surfaces of the semiconductor wafer w. And independent heating control is possible.

[0004]

However, in the vertical heat treatment apparatus, since the heat treatment furnace is of a vertical type in spite of performing independent heating control for each zone, internal heat convection occurs. In some cases, there is a problem that the controllability is deteriorated or the load on the resistance heating element is increased due to the influence of A or heat conduction. In particular, since the zones at the upper and lower ends tend to be lower in temperature than the central zone, it is necessary to increase the temperature by increasing the voltage (load). In addition, in the lower zone, in addition to heat radiation B from the furnace port, there is a large amount of heat escape due to heat convection and heat conduction. Have to be forced.

The present invention has been made in view of the above circumstances, and has as its object to provide a vertical heat treatment apparatus in which heat escape is reduced and zone heating efficiency and controllability are improved.

[0006]

Means for Solving the Problems In the present invention, claim 1 is provided.
In the invention according to the invention, a cylindrical heater which is divided into a plurality of zones in the height direction and is capable of controlling the heating is installed around a processing container accommodating a large number of objects to be processed arranged and supported in the height direction. In a vertical heat treatment apparatus having a metal contamination prevention pipe disposed between the heater and the processing vessel, a low heat conductive member is provided at a portion corresponding to a zone boundary of the heater in the metal contamination prevention pipe. I do.

According to a second aspect of the present invention, there is provided a cylinder which is divided into a plurality of zones in a height direction around a processing vessel for accommodating a large number of objects to be processed arranged and supported in the height direction and capable of controlling heating. In a vertical heat treatment apparatus provided with a heater in a shape, a shielding plate is disposed between the processing container and the heater at an interval corresponding to a zone boundary thereof.

According to a third aspect of the present invention, there is provided a cylinder which is divided into a plurality of zones in a height direction around a processing vessel for accommodating a large number of objects to be arranged and supported in the height direction, and is capable of controlling heating. In a vertical heat treatment apparatus in which a metal-shaped heater is installed and a metal contamination prevention pipe is arranged between the heater and the processing container, a low heat conductive member is interposed at a portion of the metal contamination prevention pipe corresponding to a zone boundary of the heater. And a shielding plate is disposed between the metal contamination prevention pipe and the heater at an interval corresponding to the zone boundary.

[0009]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a schematic vertical sectional view of a vertical heat treatment apparatus showing a first embodiment of the present invention. This vertical heat treatment apparatus includes, for example, a vertical heat treatment furnace 1 constituting a high-temperature furnace or a diffusion furnace. This heat treatment furnace 1 has many, for example, 1
A reaction tube 3 which is a processing vessel for accommodating about 50 objects to be processed, for example, semiconductor wafers w, arranged in a boat 2 as a support at predetermined intervals in a height direction, and covers the periphery of the reaction tube 3. The reaction tube is set at a desired temperature, for example, 6
It is mainly composed of a cylindrical heater 4 which is a heating means capable of heating to about 00 to 1200 ° C., and a metal contamination prevention tube 5 arranged between the heater 4 and the reaction tube 3.

The reaction tube 3 is made of a material having heat resistance and corrosion resistance, for example, quartz, and is formed in a vertically long cylindrical shape having a closed upper end and an open lower end. A gas introduction pipe for introducing a processing gas or an inert gas, an exhaust pipe for exhausting the inside of the furnace, and the like are provided at a lower portion of the reaction tube 3 (not shown). The reaction tube 3 may have a double tube structure of an inner tube and an outer tube.

The lower end of the reaction tube 3 is attached to the lower side of the base plate 6 by an attachment member (not shown). The base plate 6 is made of, for example, stainless steel,
It is provided horizontally in the housing of the vertical heat treatment apparatus. An opening (furnace port) 7 through which the reaction tube 3 is inserted in the vertical direction is formed in the base plate 6, and a heat insulating material 8 is attached to the opening 7 to suppress heat radiation from the opening 7. ing.

Below the reaction tube 3, a lid 9 for opening and closing the lower end opening is provided so as to be vertically movable by a lifting mechanism (not shown). The boat 2 is placed on the lid 9 via a heat retaining tube 10. The lifting mechanism moves the boat 2 into and out of the reaction tube 3 and opens and closes the lid 9. Further, the boat 2 is provided with a heat insulating cylinder 10 in order to uniformly process the semiconductor wafer w in the surface.
There is provided a rotation mechanism (not shown) for rotating together.

In the heater 4, a resistance heating element (resistance heating wire) 12 is arranged on the inner periphery of a cylindrical heat insulating material 11 surrounding the periphery of the reaction tube 3 in a meandering manner in the circumferential direction or spirally in the longitudinal direction. It is configured. The heater 4 has a configuration in which the resistance heating element 12 is divided into a plurality of, for example, five zones Z1 to Z5 in the height direction, and the temperature can be independently controlled for each zone. The outside of the heat insulating material 11 is covered with a water cooling jacket (not shown). The heater 4 is provided on a base plate 6.

The metal contamination prevention tube 5 prevents contamination of the semiconductor wafer w by metal released from the resistance heating element of the heater 4 and is made of, for example, silicon carbide (SiC). The metal contamination prevention tube 5 is formed in a vertically long cylindrical shape having a closed upper end and an open lower end so as to surround the periphery of the reaction tube 3, and is provided on the heat insulating material 8 of the base plate 6.

In order to suppress the heat escape due to the heat conduction of the metal contamination prevention tube 5, that is, to suppress or reduce the heat escape due to the heat conduction from each zone to another (adjacent) zone by the metal contamination prevention tube 5. For this purpose, the metal contamination prevention pipe 5 is provided with a low thermal conductive member 13 at a portion corresponding to the zone boundary Zx of the heater 4. The metal contamination prevention pipe 5 is divided at the position of each zone boundary Zx of the heater 4, and the low heat conduction member 13 is sandwiched between the divided surfaces.
The low heat conductive member 13 is formed in a ring shape so as to correspond to the cross section of the metal contamination prevention tube 5. Low heat conductive member 13
Is set as appropriate. Low heat conductive member 13
For example, a heat insulating material is applicable.

According to the vertical heat treatment apparatus configured as described above, since the low heat conductive member 13 is interposed at the portion corresponding to the zone boundary Zx of the heater 4 in the metal contamination prevention pipe 5, it can be connected to another zone. Can be reduced by heat conduction due to heat conduction. In other words, the metal contamination prevention pipe 5
Correspond to the heating zone of the heater 4,
, Heat insulation between the zones can be achieved, and uniform heat distribution in the zones can be achieved. This makes it possible to effectively control heating for each zone, and improves zone heating efficiency and controllability.

FIG. 2 is a schematic vertical sectional view of a vertical heat treatment apparatus showing a second embodiment of the present invention. In the present embodiment, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted. This vertical heat treatment apparatus includes, for example, a vertical heat treatment furnace 1 constituting a low-temperature furnace or a CVD furnace. The heat treatment furnace 1 mainly includes a reaction tube 3 and a heater 4. There is no metal contamination prevention pipe.

Between the reaction tube 3 and the heater 4, a shielding plate 14 is arranged at an interval corresponding to the zone boundary Zx of the heater 4 in order to suppress or reduce heat escape due to thermal convection. The shielding plate 14 is formed in a thin ring shape so as to be disposed in the annular space 15 between the reaction tube 3 and the heater 4. The shielding plate 14 includes a plurality of, for example, three to four columns 16 erected from the lower heat insulating material 8 in the annular space 15.
For example, a plurality of, for example, four, heaters are attached at intervals corresponding to the zone length of the heater 4.

The inner periphery of the shield plate 14 is not in contact with the reaction tube 3, and the outer periphery of the shield plate 14 is not in contact with the heater 4. The shielding plate 14 and the support 16 are formed of, for example, quartz or silicon carbide (SiC). In addition, it is preferable that the surface of the shielding plate 14 be subjected to a mirror surface (reflection surface) process by, for example, a CVD process or the like in order to suppress transmission of radiant heat from the heater 4.

According to the vertical heat treatment apparatus of this embodiment having the above configuration, the shielding plate 14 is provided between the reaction tube 3 and the heater 4 (annular space 15) at an interval corresponding to the zone boundary Zx of the heater 4. Are arranged, heat escape due to heat convection can be reduced, and effective heating control can be performed for each zone, thereby improving zone heating efficiency and controllability. At a high temperature of, for example, 600 ° C. or more, the influence of the radiant heat from the heater 4 is greater than the heat convection.

FIG. 3 is a schematic vertical sectional view of a vertical heat treatment apparatus showing a third embodiment of the present invention. In the present embodiment, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted. The heat treatment furnace 1 of this vertical heat treatment apparatus includes a reaction tube 3, a heater 4, and a metal contamination prevention tube 5 disposed between the heater 4 and the reaction tube 3, as in the first embodiment. It is mainly composed.

A low heat conductive member 13 is interposed in a portion of the metal contamination prevention tube 5 corresponding to the zone boundary Zx of the heater, and a space between the metal contamination prevention tube 5 and the heater 4 (annular space 17). Is the zone boundary Z of the heater 4
The shielding plates 14 are arranged at intervals corresponding to x. That is, the vertical heat treatment apparatus of the present embodiment is configured as a composite type of the first and second embodiments.

According to the vertical heat treatment apparatus of the present embodiment,
Zone boundary Z of heater 4 in the metal contamination prevention pipe 5
x, a low heat conductive member 13 is interposed at a portion corresponding to x, and a shielding plate 14 is arranged between the metal contamination prevention pipe 5 and the heater 4 at an interval corresponding to the zone boundary Zx. It is possible to reduce both heat escape by heat conduction to other zones and heat escape by heat convection,
Zone heating efficiency and controllability are sufficiently improved. In the lower zone 1Z, in addition to heat radiation from the furnace port, there was much heat escape due to heat convection and heat conduction, but since heat escape due to heat convection and heat conduction was reduced, the load on the resistance heating element 12 was also reduced. And the durability can be improved. The shielding plate 14
May be provided on the low heat conduction member 13 on the metal contamination prevention tube 5 side without using the support 16, or may be provided on the zone boundary Zx on the heater 4 side.

The embodiment of the present invention has been described in detail with reference to the drawings. However, the present invention is not limited to the above embodiment, and various design changes and the like can be made without departing from the gist of the present invention. Is possible. For example, in order to reduce heat radiation from the furnace port, a mirror surface (reflection surface) is provided on the upper surface of a heat insulating material provided at the opening of the base plate so that radiant heat from the heater is reflected inward without transmitting. May be. Further, the heat treatment furnace may be a decompression type, in which case,
A metal manifold, for example, a stainless steel manifold having a gas introduction pipe and an exhaust pipe is hermetically connected to the lower end of the reaction pipe, and a vacuum exhaust system having a vacuum pump and a pressure control valve is connected to the exhaust pipe. As the object to be processed, for example, a glass substrate, an LCD substrate, or the like can be applied other than the semiconductor wafer.

[0026]

In summary, according to the present invention, the following effects can be obtained.

(1) According to the first aspect of the present invention, a plurality of zones are divided in a height direction around a processing container for accommodating a large number of objects to be processed arranged and supported in the height direction. In a vertical heat treatment apparatus in which a controllable cylindrical heater is installed and a metal contamination prevention pipe is arranged between the heater and the processing vessel, a portion corresponding to a zone boundary of the heater in the metal contamination prevention pipe is provided. Since the low heat conduction member is provided, heat escape due to heat conduction to other zones can be reduced, and zone heating efficiency and controllability are improved.

(2) According to the second aspect of the present invention, a plurality of zones are divided in a plurality of zones in a height direction around a processing container for accommodating a large number of objects to be processed arranged and supported in the height direction. In a vertical type heat treatment apparatus having a controllable cylindrical heater, a shield plate is arranged between the processing vessel and the heater at an interval corresponding to the zone boundary, so that heat escape due to heat convection is reduced. And zone heating efficiency and controllability are improved.

(3) According to the third aspect of the invention, a plurality of processing objects are arranged and supported in the height direction. In a vertical heat treatment apparatus in which a controllable cylindrical heater is installed and a metal contamination prevention pipe is arranged between the heater and the processing vessel, a portion corresponding to a zone boundary of the heater in the metal contamination prevention pipe is provided. Since a low heat conducting member is interposed and a shielding plate is arranged between the metal contamination prevention pipe and the heater at a space corresponding to the zone boundary, heat dissipation to other zones and heat escape due to heat convection are reduced. And zone heating efficiency and controllability are improved.

[Brief description of the drawings]

FIG. 1 is a schematic vertical sectional view of a vertical heat treatment apparatus showing a first embodiment of the present invention.

FIG. 2 is a schematic vertical sectional view of a vertical heat treatment apparatus showing a second embodiment of the present invention.

FIG. 3 is a schematic vertical sectional view of a vertical heat treatment apparatus showing a third embodiment of the present invention.

FIG. 4 is a schematic vertical sectional view of a conventional vertical heat treatment apparatus.

[Explanation of symbols]

 w Semiconductor wafer (object to be processed) 3 Reaction tube (processing vessel) 4 Heater Zx Zone boundary 5 Metal contamination prevention tube 13 Low heat conductive member 14 Shield plate

Claims (3)

[Claims] 1. A cylindrical heater which is divided into a plurality of zones in a height direction and is capable of controlling heating is provided around a processing container which accommodates a large number of objects to be processed arranged and supported in the height direction. In a vertical heat treatment apparatus having a metal contamination prevention pipe disposed between the heater and the processing vessel, a low heat conductive member is provided at a portion corresponding to a zone boundary of the heater in the metal contamination prevention pipe. Vertical heat treatment equipment. 2. A cylindrical heater which is divided into a plurality of zones in the height direction and is capable of controlling heating is provided around a processing container which accommodates a large number of objects to be processed arranged and supported in the height direction. The vertical heat treatment apparatus according to claim 1, wherein a shielding plate is arranged between the processing vessel and the heater at an interval corresponding to a zone boundary. 3. A cylindrical heater, which is divided into a plurality of zones in the height direction and is capable of controlling the heating, is provided around a processing container for accommodating a large number of objects to be processed arranged and supported in the height direction. In a vertical heat treatment apparatus having a metal contamination prevention pipe disposed between the heater and the processing vessel, a low heat conduction member is provided at a portion of the metal contamination prevention pipe corresponding to a zone boundary of the heater, and A vertical heat treatment apparatus wherein a shielding plate is arranged between a pollution prevention pipe and a heater at an interval corresponding to the zone boundary.