JPH085547Y2 - Vertical diffusion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a vertical diffusion device used in a semiconductor manufacturing process.

[Conventional technology]

Conventionally, the vertical diffusion device has a structure as shown in FIG.

In FIG. 2, 1 is a vertical tubular heater, 2 is a metallic heater base for supporting the weight of the tubular heater 1, 3 is a quartz reaction tube provided inside the tubular heater 1, and 4 is this quartz reaction tube 3 With a metal receiving flange that holds the weight of
It is fixed to the heater base 2. Reference numeral 5 is a quartz pedestal on which a wafer boat is placed, 6 is a receiving plate on which the pedestal 5 is placed, 7 is a quartz cap, and a spring 8 held by the receiving plate 6 allows the end of the reaction tube 3 to be closely attached. It 9
Is an elevator arm, which holds a pedestal 5, a receiving plate 6, a cap 7, and a spring 8, and is vertically moved by an elevator drive unit.

In such a conventional apparatus, the silicon wafer on the boat placed on the pedestal 5 is introduced from above the reaction tube 3 and is exhausted from the exhaust boat 10 below the reaction tube 3 and the tubular heater 1. Is heat treated. The reaction gas may use a corrosive gas, and in particular, the receiving plate 6 is directly exposed to the corrosive gas. Furthermore, the furnace mouth is required to have a structure that does not leak exhaust gas.

[Problems to be solved by the device]

However, in the above conventional apparatus, the reaction tube 3
There is a problem that corrosive gas leaks from the contact portion of the cap 7 and the gap between the cap 7 and the receiving plate 6, which not only impairs safety but also corrodes the peripheral parts including the receiving plate 6.

[Means for solving the problem]

In order to solve the above problems, the apparatus of the present invention comprises a quartz reaction tube 3 forming a processing region for heat treating a wafer and a heater base 2 for heating the wafer to a predetermined temperature as shown in FIG. A supported heater 1, a wafer boat that holds a plurality of the wafers, a wafer boat that holds the wafer boat, and is supported by a receiving plate 6.
In the vertical diffusion device having the boat pedestal 5 of the boat, an elastic airtight packing 11 having corrosion resistance is interposed between the flange portion of the reaction tube 3 and the flange portion of the pedestal 5. 5, the flange portion of the reaction tube 3 is pressed from above by a retainer 14 fixed to the heater base 2,
The holding tool 14 and the receiving plate 6 are provided with cooling water passages 12 and 13, respectively.

[Action]

In a state where the pedestal 5 and the receiving plate 6 holding the corrosion-resistant elastic airtight packing 11 are moved upward by the elevator and the wafer boat on the pedestal 5 is set in the reaction tube 3, the elasticity of the packing 11 causes the reaction tube to move. Since the 3 and the packing 11 and the pedestal 5 and the packing 11 are in close contact with each other, corrosive exhaust gas does not leak to the outside of the furnace opening.

Further, since the packing 11 is cooled by the presser 14 and the cooling water passages 12 and 13 of the receiving plate 6, the packing 11 serves to maintain a normal sealing action, and at the same time, the cooling water passage
No. 12 and 13 need only be provided on existing parts, and there is no need to provide a separate cooling section having a cooling water passage.

Further, by making the members that come into contact with corrosive exhaust gas, that is, the reaction tube 3, the pedestal 5, and the packing 11 be corrosion-resistant packing, they will not corrode.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the construction of an embodiment of the device of the present invention.

In the figure of the stand 1, 2 is a metallic heater base that supports the vertical tubular heater 1, and 3 is a quartz reaction tube having a flange-shaped lower portion, which is provided inside the tubular heater 1. Reference numeral 4 denotes a metal receiving flange that holds the reaction tube 3, and is fixed to the heater base 2. Reference numeral 5 denotes a quartz pedestal on which a wafer boat (not shown) is mounted, and has a structure in which a corrosion-resistant elastic gas-tight packing 11 for preventing gas leakage can be attached to the lower part. Reference numeral 6 denotes a water-cooled receiving plate that holds the receiving table 5, and is held by the elevator arm 9. 14 is
A pressing ring having a water cooling structure for pressing the flange portion of the reaction tube 3 against the receiving flange 4, and is fixed to the receiving flange 4.

Reference numeral 11 denotes a corrosion-resistant elastic gas-tight packing for preventing gas leakage, which is interposed between the reaction tube 3 and the receiving table 5, and is held on the receiving table 5. Reference numerals 12 and 13 denote cooling water passages provided in the holding ring 14 and the receiving plate 6, respectively, and the cooling water flows through the passages 12 and 13.

The material of the packing 11 is required to be elastic such as rubber, and the shape of the packing is square in this example, but it is not necessary to be square and may be circular.

In the above configuration, the pedestal 5 and the receiving plate 6 holding the gas leak preventing elastic hermetic packing 11 are moved upward by the elevator (driving unit), and the wafer boat on the pedestal 5 is set in the reaction tube 3. In the illustrated state, the reaction gas is introduced from above the reaction tube 3 and the exhaust boat 10 below the reaction tube 3
The wafers further evacuated and placed on the wafer boat on the pedestal 5 are heat-treated by the reaction gas and the tubular heater 1.

In this case, since the reaction tube 3 and the packing 11 and the pedestal 5 and the packing 11 are in close contact with each other due to the elasticity of the packing 11, corrosive exhaust gas does not leak to the outside of the furnace port.

Further, the temperature around the packing 11 becomes extremely high, but the packing 11 is cooled by the holding ring 14 of the water cooling structure and the cooling water flowing through the cooling water passages 12 and 13 of the receiving plate 6, so that the normal sealing can be achieved. It will serve to retain the action.

Further, by making the members contacting the corrosive exhaust gas, that is, the reaction tube 3, the pedestal 5 and the packing 11 made of corrosive resistant quartz and corrosive resistant packing, these do not corrode.

As described above, according to the present embodiment, since the corrosion-resistant elastic gas-tight packing 11 for preventing gas leakage, which is interposed between the quartz reaction tube 3 and the pedestal 5, is held on the pedestal 5, the packing 11 Due to the elasticity, the reaction tube 3 and the packing 11 and the pedestal 5 and the packing 11 are in close contact with each other, so that corrosive exhaust gas does not leak to the outside of the furnace opening, and it is safe and corrodes surrounding parts. There is no fear.

Further, since the packing 11 can be cooled by the pressing ring 14 having the water cooling structure and the cooling water passages 12 and 13 of the receiving plate 6, the heat resistance of the packing 11 does not become a problem and the normal sealing action is maintained. Cooling water passage
12 and 13 need not be installed on existing parts, which is not only economical, but the parts that come into contact with corrosive exhaust gas, that is, the reaction tube 3, pedestal 5 and packing 11 are made of corrosion-resistant quartz and corrosion-resistant. These are not corroded by using the packing having the property of heat resistance.

Therefore, the corrosive gas is the reaction tube 3, the pedestal 5, and the packing.
Since it does not corrode 11 and leaks to the outside of the furnace opening, it is possible to secure safety for a long period of time and avoid corroding surrounding parts including the receiving plate 6.

[Effect of device]

As can be understood from the above description, according to the present invention, a corrosion-resistant elastic airtight packing is provided between the flange portion of the quartz reaction tube 3 and the flange portion of the quartz pedestal 5 that holds the boat.
Since 11 is interposed, corrosive exhaust gas does not leak outside the furnace mouth, it is safe, there is no risk of corroding surrounding parts, and the airtight packing 11 is installed in the cooling water passage 1
Since it is cooled by 2, 13, the durability of the packing 11 is significantly improved and the sealing property can be maintained, and the cooling water passages 12, 13 are respectively the existing parts, that is, the retainer 14 and the retainer 14. Only the plate 6 needs to be provided, and it is economical because it is not necessary to provide a cooling section having a separate cooling water passage.

[Brief description of drawings]

FIG. 1 is a sectional view showing the constitution of an embodiment of the device of the present invention, and FIG. 2 is a sectional view showing the constitution of an example of a conventional device. 1 ... Vertical tubular heater, 2 ... Heater base, 3 ... Quartz reaction tube, 4 ... Receiving flange, 5 ... Quartz pedestal, 6 ...
… Receiving plate, 9 …… elevator arm, 10 …… exhaust boat, 11 …… corrosion-resistant elastic airtight packing for preventing gas leakage, 12 …… cooling water passage, 13 …… cooling water passage, 14 …… pressing ring (Ingredients).

Claims (1)

[Scope of utility model registration request] 1. A quartz reaction tube for forming a processing region for heat-treating a wafer, a heater supported by a heater base for heating the wafer to a predetermined temperature, and a wafer boat for holding a plurality of the wafers. A vertical diffusion device that holds the wafer boat and is supported by a receiving plate and has a quartz pedestal of the boat, in which corrosion resistance is provided between the flange portion of the reaction tube and the flange portion of the pedestal. The elastic tube is held on the pedestal with the elastic airtight packing interposed therebetween, and the flange portion of the reaction tube is pressed from above by a holding member fixed to the heater base, and cooling water passages are provided in the holding member and the receiving plate, respectively. A vertical diffusion device characterized by being provided.