JP2557105B2 - Vertical heat treatment furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Object of the Invention [Industrial field of use] The present invention relates to a vertical heat treatment furnace, and particularly to a wafer heat treatment jig and a support for taking out a semiconductor wafer from an inner space of a furnace core tube. The present invention relates to a vertical heat treatment furnace in which a heat radiation prevention tube is arranged around a table.

[Prior Art] Conventionally, as this type of vertical heat treatment furnace, a wafer heat treatment jig, which is placed on a support table arranged in a furnace lid main body and holds a semiconductor wafer, is used together with the support table. It has been proposed that the semiconductor wafer is inserted into the inner space of the core tube, an appropriate heat treatment is performed on the semiconductor wafer, and then taken out from the inner space of the furnace core tube together with the support table.

Further, as this type of vertical heat treatment furnace, a wafer heat treatment jig, which is placed on a support table arranged in the furnace lid body and holds a semiconductor wafer, is used together with the support table in the inner space of the furnace core tube. In order to alleviate the thermal history of the semiconductor wafer when it is inserted and taken out, a wafer heat treatment jig surrounded by an inner tube has been proposed.

[Problems to be solved] Therefore, in the conventional vertical heat treatment furnace, (i) the temperature of the ambient environment is changed by the heat of the semiconductor wafer, the wafer heat treatment jig, and the support table taken out from the inner space by the furnace core tube. It has the drawback of being pushed up, especially (i
i) When arranging the inner cylindrical tube around the wafer heat treatment jig, the heat capacity is further increased, so that there is a drawback that the temperature of the ambient environment is further increased. As a result, (iii) temperature control of the ambient environment There is a drawback that it becomes complicated, and (iv) there is a drawback that devices existing in the surrounding environment are damaged.

Therefore, in order to eliminate these drawbacks, the present invention provides a vertical type in which a heat radiation prevention tube is arranged around the wafer heat treatment jig and the supporting table when the semiconductor wafer is taken out from the inner space of the furnace core tube. The purpose is to provide a heat treatment furnace.

(2) Configuration of the Invention [Means for Solving Problems] In the vertical heat treatment furnace of the present invention, a semiconductor wafer is held in a furnace core tube while being held by a wafer heat treatment jig on a support table mounted on a furnace lid body. In a vertical heat treatment furnace which is inserted into the internal space of the machine for heat treatment and is taken out after the heat treatment, an inner cylindrical tube integrally supported to be vertically movable and a heat radiation prevention tube surrounding the inner cylindrical tube are provided. During the heat treatment, the wafer processing jig rises and the inner tube and heat radiation prevention tube rise, and the inner tube is placed inside the furnace core tube so as to surround the wafer heat treatment jig. The heat radiation prevention tube is arranged outside the furnace core tube, and the wafer heat treatment jig descends when the wafer processing jig is taken out of the inner space of the furnace core tube, and the inner tube and the heat radiation prevention tube Is lowered and the inner tube is Surrounds the periphery of the heat treatment jig and heat radiation prevention tube is characterized in that surrounding the periphery of the inner tube.

[Operation] Since the vertical heat treatment furnace according to the present invention has the above-described configuration, (i) it has an effect of suppressing the temperature of the ambient environment from being raised when the semiconductor wafer is taken out from the inner space of the furnace core tube, As a result, (ii) it has the function of facilitating the temperature control of the surrounding environment, and (iii) it has the function of suppressing the damage to the equipment existing in the surrounding environment due to the high temperature.

[Examples] Next, the vertical heat treatment furnace according to the present invention will be specifically described with reference to its preferred examples. However, the examples described below are provided for facilitating or facilitating the understanding of the present invention, and not for limiting the present invention. In other words, each member disclosed in the embodiments described below includes all design changes and equivalent replacements within the spirit and technical scope of the present invention.

FIG. 1 is a sectional view showing an embodiment of a vertical heat treatment furnace according to the present invention.

2 to 7 are sectional views for sequentially explaining a series of operating states of the embodiment of FIG.

FIG. 8 is a partial perspective view showing a part of the embodiment shown in FIG. 1, and particularly shows the inner tube body 71 of the inner tube 70A .

FIG. 9 is a partial perspective view showing a part of the embodiment shown in FIG. 1, particularly showing the heat radiation prevention tube 70B .

First, the configuration of an embodiment of the vertical heat treatment furnace according to the present invention will be described in detail with reference to FIGS. 1 to 9.

10 is a vertical heat treatment furnace according to the present invention, a furnace core tube 20 for heat treating semiconductor wafers (not shown) are formed in a suitable material such as quartz, surrounding furnace core tube 20 A soaking tube 30 which is arranged at an appropriate interval through the furnace so as to facilitate ensuring a soaking area in the furnace core tube 20 .
A heating member 40 arranged around the soaking tube 30 , a heat insulating tube 50 arranged around the heating member 40 , and a suitable material such as stainless steel for holding the furnace core tube 20. Housing 60 , an inner cylinder tube 70A having an inner cylinder tube body 71 formed of an appropriate material such as quartz and capable of being inserted into and removed from the inner space of the furnace core tube 20 , and the inner cylinder tube 70A Formed by a heat radiation prevention tube 70B which is arranged around the inner cylindrical tube 70A when it is taken out from the tube 20 and shields heat radiated from the inner cylindrical tube 70A, and a high-purity material such as quartz or silicon carbide that can be used at high temperatures. And a furnace lid 80 having a furnace lid body 81 that directly abuts against the open end portion 71A of the inner cylindrical tube body 71.

The furnace core tube 20 is extended from the outside of the heat insulating tube 50 and is extended in the axial direction along the outer peripheral surface thereof, and is then opened to the internal space 21 at the top portion, and is a gas supply for supplying an appropriate processing gas. A pipe 22 and a gas discharge pipe 23 that is opened in the vicinity of the opening end 21A and is extended to the outside of the heat insulating pipe 50 to remove the used processing gas from the internal space of the furnace core pipe 20 to the outside. I have a package. It is preferable that both the gas supply pipe 22 and the gas discharge pipe 23 are formed of an appropriate material such as quartz as many portions as possible are located inside the heat insulating pipe 50 .

Liner tube 30, have been prepared by, for example, silicon carbide, and is disposed so as to surround the entire length of the furnace core tube 20 to secure to extend the soaking section of a furnace core tube 20.

The heating member 40 is arranged outside the soaking tube 30 , and is appropriately arranged to secure a soaking region along the axial direction of the furnace core tube 20 .

The heat insulating tube 50 is made of an appropriate material such as glass fiber, and has a furnace core tube 20 , a soaking tube 30, and a heating member.
It encloses 40 as a whole.

The housing 60 includes a furnace core tube support portion 61 for supporting the lower surface of the support projections 24 formed on the outer peripheral surface of the opening end portion 21A of the core tube 20, preventing thermal radiation below the outer circumference of the insulating tube 50 tube
It has a housing hole 62 for housing 70B .

The inner tube 70A is configured to be insertable into and removable from the open end 21A of the inner space 21 of the furnace core tube 20 , and a gas hole for removing the used processing gas near the open end 71A. 71
The inner cylinder body 71 in which a is formed and the lower surface of the support projection 72 formed on the outer peripheral surface of the opening end portion 71A of the inner cylinder body 71 are supported by the inner peripheral support portion 73A and Replace the tube body 71 with the furnace core tube 2
The inner cylinder tube moving member 73 to be inserted into or removed from the inner space 21 of 0 , the drive shaft 74 arranged at one end of the inner cylinder tube moving member 73, and the drive shaft 74. Similarly to the guide shaft 75 arranged at one end of the inner cylinder tube moving member 73, and the furnace core of the housing 60 when the inner cylinder tube body 71 is inserted into the inner space 21 of the furnace core tube 20. In order to ensure a seal with the lower surface of the tube support portion 61, an O-ring 76 disposed on the upper surface in the vicinity of the inner peripheral support portion 73A is included.

The heat radiation prevention pipe 70B is made of stainless steel, quartz, silicon carbide, heat-resistant plastic, or the like, and is disposed on the inner cylinder pipe moving member 73. When the heat radiation prevention pipe 70B is moved by the inner cylinder pipe moving member 73, the gas supply pipe 22 And gas exhaust pipe
Slit to avoid creating interference with 23
77a and 77b are formed.

The furnace lid 80 is a furnace lid body 81 formed of a high-purity material that can be used at high temperature, such as quartz or silicon carbide, that is in direct contact with the lower surface of the open end portion 71A of the inner tube body 71.
It is made of appropriate material such as stainless steel.
For holding the furnace lid holding member 82, and a furnace lid moving member 83 for supporting the lower surface of the furnace lid holding member 82 and for moving the furnace lid body 81 toward and away from the open end 71A of the inner tube body 71. And the furnace lid main body 81, which is disposed on the upper surface of the furnace lid moving member 83.
An elastic member 84 that functions as a cushioning material when the inner tube body 71 is brought into contact with the open end 71A of the inner tube main body 71, a drive shaft 85 disposed at one end of the furnace lid moving member 83, and a drive member Like the shaft 85, the guide shaft 86 disposed at one end of the furnace lid moving member 83 and the furnace lid body 81 when the furnace lid body 81 abuts on the lower surface of the opening end 71A of the inner tube body 71. It includes an O-ring 87 arranged on the upper surface of the furnace lid holding member 82 for ensuring a seal between the upper surface of the holding member 82 and the lower surface of the inner tube moving member 73.

Further, the operation of one embodiment of the vertical heat treatment furnace according to the present invention will be described in detail with reference to FIGS. 1 to 9.

(Semiconductor Wafer Inserting Operation) The furnace lid moving member 83 is moved downward by the drive shaft 85 and the guide shaft 86, and the inner cylindrical tube body 71 and the heat radiation prevention tube 70B are driven by the drive shaft 73 and the guide shaft 74.
In the state of being inserted into the inner space 21 of the furnace core tube 20 and the accommodation hole 62 of the housing 60 (see FIG. 1), respectively,
A wafer supporting member 90 holding a semiconductor wafer (not shown) to be heat-treated is placed on the furnace lid main body 81. That is, the wafer heat treatment jig 91 holding the semiconductor wafer to be heat treated is placed on the support table 92 arranged on the furnace lid body 81 (see FIG. 2).

After that, by moving the inner cylinder tube moving member 73 in the direction of arrow A ₁ by the drive shaft 74 and the guide shaft 75, the inner cylinder 21 is inserted from the inner space 21 of the furnace core tube 20 and the accommodation hole 62 of the accommodation hole of the housing 60. The tube body 71 and the heat radiation prevention tube 70B are pulled out at the same time and are arranged around the wafer support member 90, that is, the wafer heat treatment jig 91 holding the semiconductor wafer and the support table 92 (see FIG. 3). At this time, from the inner space 21 of the furnace core tube 20 to the inner tube body 71
Since the heat radiation prevention tube 70B is arranged around the heat radiation prevention tube 70B when it is drawn out, it is possible to prevent the temperature of the ambient environment (for example, a clean room) from being raised by the heat of the inner tube body 71. As a result, temperature control of the surrounding environment can be facilitated, and damage to the devices existing in the surrounding environment due to high temperature can be suppressed.

Next, the inner shaft moving member 73 is moved in the arrow A ₂ direction by the drive shaft 74 and the guide shaft 75, and the furnace lid moving member 83 is moved in the arrow B ₁ direction by the drive shaft 85 and the guide shaft 86 (third part). See figure). By moving both the inner tube moving member 73 and the furnace lid moving member 83 upward, the wafer supporting member 90, that is, the wafer heat treatment jig 91 holding the semiconductor wafer and the support table 92, the inner tube tube main body 71 and the heat It is inserted into the internal space 21 of the furnace core tube 20 while being surrounded by the radiation prevention tube 70B and protected by the inner tube body 71. As a result, when the semiconductor wafer held by the wafer supporting member 90 is inserted into the internal space 21 of the furnace core tube 20 , the temperature difference θ _Δ generated between the central temperature θ ₁ and the peripheral temperature θ ₂ is increased. It is suppressed within a certain range, and crystal defects (so-called “slip”) do not occur.

The inner tube moving member 73 is finally brought into contact with the lower surface of the furnace core tube support portion 61 of the housing 60 via an O-ring 76. Further, the furnace lid holding member 82 is finally brought into contact with the lower surface of the inner tube moving member 73 via the O-ring 87 (see FIG. 4).

In this state, a semiconductor wafer held by the wafer heat treatment jig 91 while supplying an appropriate processing gas to the inner space 21 of the furnace core tube 20 through the gas supply tube 22 as shown by an arrow C ₁ (see FIG. Heat treatment (not shown) is appropriately performed.

The used processing gas flows from the periphery of the semiconductor wafer held by the wafer heat treatment jig 91 to the gas holes in the inner cylindrical tube body 71.
After being eliminated via the 71a as indicated by arrow C ₂ , it is eliminated via the gas discharge pipe 23 from the internal space 21 of the furnace core tube 20 toward the outside.

(Semiconductor Wafer Extracting Operation) After the heat treatment of the semiconductor wafer held by the wafer heat treatment jig 91 is completed, the inner tube moving member 73 is moved in the direction of arrow A ₃ by the drive shaft 74 and the guide shaft 75, And drive shaft 85 and guide shaft
The furnace lid moving member 83 is moved in the direction of arrow B ₂ by 86 (see FIG. 5).

When the furnace lid moving member 83 is moved to near the initial position,
The inner cylinder tube moving member 72 is again driven by the drive shaft 74 and the guide shaft 75 to remove the wafer heat treatment jig 91 from the support table 92, as shown by an arrow A _4.
It is moved toward the open end 21A of 20 (see FIG. 6).

As a result, the semiconductor wafer held by the wafer support member 90 is surrounded by the inner tube body 71 when it is taken out from the internal space 21 of the furnace core tube 20 after the heat treatment, so that the central temperature θ ₁ The temperature difference θ _Δ between the peripheral temperature θ ₂ and the peripheral temperature θ ₂ is suppressed within a certain range, and crystal defects (so-called “slip”) do not occur.

Further, the wafer support member 90, that is, the wafer heat treatment jig 91, the support table 92, and the inner tube main body 71 are taken out from the internal space 21 of the furnace core tube 20 in a state of being surrounded by the heat radiation prevention tube 70B . Therefore, it is possible to suppress an increase in the temperature of the surrounding environment, facilitate the temperature control of the surrounding environment, and suppress damage to devices and the like existing in the surrounding environment.

After that, the inner tube body 71 is inserted into the internal space 21 of the furnace core tube 20 and the heat radiation prevention tube 70B is inserted into the housing hole 62 of the housing 60.
When the wafer is removed from the wafer supporting member 90, that is, the wafer heat treatment jig 91 and the peripheral surface of the support table 92 (see FIG. 7), the wafer heat treatment jig holds the heat-treated semiconductor wafer. 91 is the furnace lid body
It is removed by suitable means from the support table 92 located on 81 (see FIG. 1).

 Hereinafter, the above operation is repeated.

(3) Effects of the Invention As is clear from the above, the vertical heat treatment furnace according to the present invention has the effect of (i) suppressing the temperature of the surrounding environment from being raised when the semiconductor wafer is taken out from the inner space of the furnace core tube. As a result, (ii) it has the effect of facilitating temperature control of the surrounding environment, and (iii) has the effect of suppressing damage to equipment and other devices present in the surrounding environment due to high temperatures.

[Brief description of drawings]

1 is a sectional view showing an embodiment of a vertical heat treatment furnace according to the present invention, and FIGS. 2 to 7 are sectional views for sequentially explaining a series of operating states of the embodiment of FIG. 1, 8 Figure and No. 9
The drawing is a partial perspective view showing a part of the embodiment shown in FIG. 10 …… Vertical heat treatment furnace 20 …… Furnace core tube 21 …… Internal space 21A …… Opening end 22 …… Gas supply pipe 23 …… Gas discharge pipe 24 …… Support protrusion 30 …… Soaking tube 40 …… Heating member 50 …… Insulation tube 60 …… Housing 61 …… Reactor core tube support section 62 …… Accommodation hole 70A …… Inner tube section 71 …… Inner tube body 71A …… Opening end 72 …… Support projection 73 …… Inner tube moving member 73A …… Inner peripheral support 74 …… Drive shaft 75 …… Guide shaft 76 …… O ring 70B …… Heat radiation prevention tube 77a, 77b …… Slit 80 …… Furnace cover 81 …… Furnace lid main body 82 …… Furnace lid holding member 83 …… Furnace lid moving member 84 …… Elastic member 85 …… Drive shaft 86 …… Guide shaft 87 …… O ring 90 …… Wafer support member 91 …… Wafer heat treatment cure Tool 92 …… Supporting table

Claims (1)

(57) [Claims] 1. A vertical type in which a semiconductor wafer is inserted into the internal space of a furnace core tube for heat treatment while being held by a wafer heat treatment jig on a support table mounted on the furnace lid main body, and is taken out after the heat treatment. The heat treatment furnace is equipped with an inner tube that is integrally supported so that it can move up and down, and a heat radiation prevention tube that surrounds the circumference of this inner tube. The heat radiation prevention tube rises, the inner cylindrical tube is arranged in the inner space of the furnace core tube in a state of surrounding the periphery of the wafer heat treatment jig, and the heat radiation prevention tube is arranged outside the furnace core tube, When taking out the wafer processing jig from the inner space of the furnace core tube, the wafer heat treatment jig descends and the inner tube and the heat radiation prevention tube descend, so that the inner tube surrounds the wafer heat treatment jig. And heat radiation prevention tube Vertical heat treatment furnace, characterized in that surrounding the periphery of the inner tube.