JP2997310B2 - Heat treatment equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a heat treatment apparatus, and more particularly to a heat treatment apparatus capable of producing a wafer with low contamination and high yield.

[Prior art] In recent years, in semiconductor manufacturing, as the degree of integration of IC chips increases, fine dust adheres to the chips during the manufacturing process, and the yield decreases, so dust prevention measures have become an important issue. I have. Therefore, the semiconductor manufacturing apparatus is arranged in a clean room in which air sent from an air blower is blown from a ceiling through a filter and exhausted from a floor to form a vertical flow of clean air.

Among the semiconductor manufacturing apparatuses arranged in such a clean room, a vertical heat treatment apparatus, in particular, uses a quartz boat 2 to store a wafer 1 stored in a carrier (not shown) as shown in FIG.
And a heat treatment furnace 4 for heat-treating the wafer 1 supported by the quartz boat 2. When such a vertical heat treatment apparatus is arranged in a clean room 5, a filter 6 provided on the ceiling is provided. From the ceiling to the floor, but the vertical transfer of the clean air flow 7 from the ceiling did not spread because the transfer device 3 of the wafer 2 was behind the heat treatment furnace 4.

Further, when the quartz boat 2 on which the processed wafer 1 is placed is taken out from the heat treatment furnace 4 to the transfer device 3 after the heat treatment, convection of air occurs due to high temperature, and particularly, the wafer 1 is contaminated. It was easy to be done.

Therefore, the filter 8 is also provided on the side of the transfer device 3,
A horizontal clean air flow was blown so that the clean air flow 9 reached the wafer 1. Further, a side surface on which the filter 8 is provided is a door 10 that can be opened and closed from the rear side for performing maintenance of the transfer device 3.

[Problems to be Solved by the Invention] However, when the number of processed wafers in the heat treatment furnace 4 increases and the diameter of the wafer increases, the transfer device 3 also increases in size, and the side surface of the transfer device 3 provided with the filter 8 is configured. The size of the door 10 naturally increases to, for example, 2 m or more. As shown in the cross-sectional view of FIG. 5, the single door 10 is divided into two pieces because it is impossible in terms of weight and opening / closing space. Was.

However, a hinge 11 having a strength corresponding to the weight of the door 10 is required, and further, when the processed wafer 1 is unloaded from the heat treatment furnace 4, the filter 8 does not deteriorate due to the heat when the processed wafer 1 is unloaded from the heat treatment furnace 4. A metal aperture plate 12 having a heat insulating effect is provided, and a large hinge 11 is used, for example. Therefore, for example, 13.7cm
No filter was provided over the width a, and the clean air flow 9 was not delivered from that portion. Therefore, the area where the clean air flow 9 does not reach is 3a, which is three times as large as the width a where the filter 8 is not provided, with respect to the flow direction of the normal clean air flow 9.
, Air stayed in the triangular area in FIG. 5, and dust was collected in this area. However, this portion corresponds to the transport path of the wafer 1 unloaded from the carrier 14 by the transport mechanism 13 to the quartz boat 2, and contamination of the wafer cannot be avoided. For this reason, a wall is provided here to prevent the accumulation of air. It was inevitable.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described drawback, and it is possible to blow a clean gas flow from the entire side surface of the transfer device, and the wafer is contaminated by dust free from air stagnation and condensed in stagnation. It is an object of the present invention to provide a heat treatment apparatus that does not require heat treatment.

Means for Solving the Problems To achieve this object, a heat treatment apparatus of the present invention performs a heat treatment furnace for heat treating a wafer supported by a boat, and transfers a wafer between a carrier for accommodating the wafer and the boat. In a heat treatment apparatus having a transfer space, a blower that blows a gas flow, a door having a filter for purifying a gas flow attached to at least one side of the transfer space and that can be opened and closed by a hinge, and a front surface of the door. A pressure equalizing plate having a larger area than a filter for generating a gas flow by diffusing the gas flow substantially uniformly in the transfer space, wherein the pressure equalizing plate is provided to extend to a hinge portion of the door.

[Operation] In this heat treatment apparatus, a quartz boat that supports a wafer in the heat treatment apparatus and a door that can be opened and closed by a hinge are provided on at least one side of a wafer transfer space where a wafer is placed between carriers that store the wafer. . The door is provided with an air purification filter, and a blower is connected to the filter.
By providing a pressure equalizing plate provided in front of the filter with a larger area than the filter and extending to the hinge portion of the door, a clean air flow can be blown from the portion where the filter is not provided, and the transfer space is provided. Clean air is supplied to the entire transfer space without causing air stagnation.
Therefore, the wafer can be transferred in a clean state, and the wafer is not contaminated in the transfer space.

Example An example in which the heat treatment apparatus of the present invention is applied to a vertical heat treatment apparatus will be described below with reference to the drawings.

The vertical heat treatment apparatus S shown in FIG. 1 mainly includes a wafer 1 between a carrier 14 for accommodating the wafer 1 before and after the heat treatment and a quartz boat 2 which is a boat supporting the wafer 1 during the heat treatment.
And a heat-treating furnace 4 for heat-treating the wafer 1.

The heat treatment furnace 4 is provided with heaters (not shown) divided into several zones so that the wafer 1 can be uniformly heated in a plane, and further connected to a reaction gas supply system and an exhaust system (not shown) to be heated to a desired temperature. The wafer 1 can be processed, for example, formed into a film, by using a reaction gas.

A transfer device 30 is provided in a transfer space K for transferring the wafer 1 between the carrier 14 and the quartz boat 2, and includes a carrier mounting table 16 on which the carrier 14 is mounted and a transfer mechanism 13 for unloading the wafer 1. Is provided. The transfer mechanism 13 is connected to a fork (not shown) that supports a part of the wafer, has a horizontal movement mechanism, and includes a transfer arm 18. The transfer arm 18 is connected to a vertical movement mechanism and a rotation movement mechanism 19, and when the transfer arm 18 inserted into the carrier 14 by the horizontal movement mechanism rises by the vertical movement mechanism to support the wafer 1, the carrier is moved by the horizontal mechanism. The wafer is returned 180 degrees, rotated by 180 ° by a rotating mechanism, and the horizontal and vertical mechanisms are operated to sequentially transfer wafers to the empty stage of the quartz boat 2.

As shown in FIG. 2, two doors 10 are provided on the side surface of such a transfer device 30 by hinges 11 which are hinge portions.
The door 10 is provided with an air cleaning filter 8 such as a ULPA filter. A pressure equalizing plate 22 having an area approximately 20% wider than the filter 8 is provided on the front surface of the filter 8 via the region b. The pressure equalizing plate 22 is made of, for example, a steel plate having a thickness of 1.0 mm provided with a large number of holes having a diameter of 5 mm at intervals of 8 mm, and makes the pressure of the gas flow sent from the filter 8 uniform to clean the front surface of the pressure equalizing plate 22. It has the effect of pushing out air. Such a pressure equalizing plate 22 is provided to extend to a portion 24 of the hinge 11 of the door 10.

Further, as shown in FIG. 4, the filter 8 is connected to the blower 26 through the door 10. Blower 26 is a blower fan
25, and the airflow that is the gas flow from the blower fan 25
It is configured to lead to 10.

Next, the operation of the vertical heat treatment apparatus S configured as described above will be described.

Before the carrier 14 is set on the carrier mounting table 16 and the transport mechanism 13 starts operating, the blower fan 25 is continuously operated. The blower fan 25 operates and the pressure is, for example, 13 mmH ₂ O
As described above, the clean air flow flows out through the filter 8. The equalizing plate 22 provided on the front surface of the filter 8 equalizes the air pressure in the region b surrounded by the filter 8 and the equalizing plate 22, and a clean air flow C is generated in the transfer space K from the hole of the equalizing plate 22. The clean air flow C is also uniformly generated by the pressure equalizing plate 22 in the hinge portion 11 of the door 10 where the filter 8 is not provided.
Therefore, the transfer space K is filled with the clean air flow C over the entire area, and the air does not stay. Therefore, the wafer 1 can be transferred to the quartz boat 2 without contamination.

After the transfer of the wafer 1 to the quartz boat 2, the quartz boat 2 is lifted by the vertical drive mechanism 21 and inserted into the heat treatment furnace 4 to perform heat treatment.

After the heat treatment, the wafer 1 is transferred from the quartz boat 2 to the carrier 14 by reversing the above operation. Also at this time, the wafer 1 is transferred in the clean air flow C.

Also, when the maintenance of the transfer device 30 is performed, the maintenance can be performed easily by opening the door 10, and it can be performed very efficiently.

The present invention is not limited to the above-described embodiment, and can be applied to a transfer device of another device.

[Effects of the Invention] As is clear from the above description, according to the heat treatment apparatus of the present invention, a clean gas flow can be generated over the entire transfer space, so that the wafer is less contaminated and the yield is good. Can be produced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a heat treatment apparatus of the present invention,
FIG. 2 is a view showing a main part of the embodiment shown in FIG. 1, FIG. 4 is a sectional view taken along line AA 'of FIG. 2, and FIGS. 3 and 5 are views showing a conventional example. . 1 Wafer 2 Quartz boat (boat) 4 Heat treatment furnace 8 Filter 10 Door 11 Hinge 14 Carrier 22 Equalizing plate 24 Hinge part of door 26 Air blow Apparatus 30 Transfer equipment C Clean gas flow K Transfer space

Claims (1)

(57) [Claims] 1. A heat treatment apparatus comprising: a heat treatment furnace for heat treating a wafer supported by a boat; a carrier for accommodating the wafer; and a transfer space for transferring the wafer between the boats. An air blower, a door having a filter for purifying the gas flow attached to at least one side surface of the transfer space and openable and closable by a hinge, and a gas flow substantially uniform in the transfer space on a front surface of the door. A pressure equalizing plate having an area larger than that of the filter that is generated by diffusing the pressure into the filter, wherein the pressure equalizing plate is provided to extend to the hinge portion of the door.