JPS597913B2 - heat treatment furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat treatment furnace for performing treatments such as impurity diffusion, vapor phase chemical growth, and thermal oxidation on semiconductor substrates and the like.

Heat treatment furnaces such as diffusion furnaces used to manufacture semiconductor devices such as ICs (integrated circuit devices) and transistors are processing chambers that hold semiconductor wafers (substrates) to be processed inside the processing furnace made of oblong quartz tubes. Furnaces that have a structure in which the opening at one end of the furnace has a lid (cap) for closing the opening were widely adopted.

Inserting and pulling out semiconductor wafers into and out of the furnace during q heat treatment such as diffusion requires removing the lid at one end and inserting a jig operating rod into the furnace from the outside to support the semiconductor wafer. This is done by taking the jig in and out.

Furthermore, the treatment temperature during heat treatment is also measured by removing the lid and inserting a thermocouple into the furnace.

As described above, the lid of the heat treatment furnace must be removed every time the above-mentioned work is required, and operations inside the furnace such as insertion and withdrawal of semiconductor wafers and measurement of processing temperature are extremely complicated.

Also, during heat treatment, the inside of the furnace can reach a high temperature of over 1000°C, and the lid at one end of the furnace is also heated to about 60°C, so operations such as loading and unloading semiconductor wafers and measuring the processing temperature are performed using the lid. It was quite dangerous as it involved removing the

Furthermore, since transparent quartz material is generally used for the lid, the heat inside the furnace passes through the transparent quartz lid and is radiated to the outside of the furnace due to the effect of radiation, resulting in a large heat loss. . The present invention has been made to eliminate the above-mentioned drawbacks, and its purpose is to simplify operations inside the furnace, such as inserting and withdrawing objects to be processed such as semiconductor wafers into a heat treatment furnace, and measuring the temperature inside the furnace. Other objectives are to reduce the risks of heat treatment operations, to reduce heat loss in the furnace, and to enable heat treatment to be carried out under appropriate treatment conditions.

In order to achieve the above object, the gist of the present invention is to provide a furnace body, a jig support part and a lid part movable simultaneously with the jig support part,
The heat treatment furnace is characterized in that it has a pressure relief tube attached to the lid for exhausting expanding air within the lid. An embodiment of the present invention will be specifically described below with reference to the drawings. Example I FIG. 1 shows a heat treatment furnace of the present invention.

In the figure, reference numeral 1 denotes the furnace body, which is composed of a length of quartz tube. 2 is a cap for closing an opening provided at one end of the furnace body 1; a hollow tube body 3 made of quartz;
Quartz wool or alumina wool filled inside,
It is composed of a heat insulating material 4 made of SiC, Si, etc.

Reference numeral 5 represents a jig operating rod for inserting and removing a processing jig 6 placed in the furnace, and 7 represents a thermocouple for measuring the temperature within the furnace.

The jig operating rod 5 is composed of a main shaft 8 made of SiC or SiO2, a foot portion 9 that supports the main shaft, and an L-shaped (or F-shaped key-shaped) hook 10 that is hooked onto the processing jig 6. has been done. The thermocouple 7 is made of platinum wire or alumel chromel, and its conducting wire 11 is led outside through the inside of the lid. Note that a thermocouple made of alumelchromel is used in the case of relatively low heat treatment. The above lid (cap)
2 has a handle 12 on the outside to facilitate its removal.
At the same time, a pressure relief tube 13 is attached to reduce the air pressure inside the hollow tube lid.

A jig operating rod 5 for inserting and removing the processing jig 6 and a thermocouple 7 for measuring temperature are attached to the inside of the lid portion 2. That is, the jig operating rod 5 and the thermocouple 7 are attached to the lid part 2 having the handle 8 and the pressure relief tube 9, and the three parts consisting of the lid part 2, the jig operating rod 5, and the thermocouple 7 are integrated. ing. Therefore, by removing the lid part 2 from one end of the furnace, the jig operating rod 5 and the thermocouple 7 can be pulled out from inside the furnace at the same time, and by attaching the lid part 2 to the opening at one end of the furnace, the jig operating rod 5 and the thermocouple 7 can be pulled out at the same time. A jig operating rod 5 and a thermocouple 7 can be inserted into the furnace. During heat treatment such as diffusion, a large number of semiconductor wafers 14 are supported by the processing jig 6, and the processing jig 6 supports the semiconductor wafers 14 by the jig operating rod 5, which is integrated with the lid part 2. Insert into the furnace.

When the jig operating rod 5 is inserted deep into the furnace, the processing jig 6 reaches a predetermined position within the furnace, and at the same time, one end opening of the furnace is closed by the lid 2. Note that since the thermocouple r is integrally attached to the lid portion 2, the thermocouple 7 is installed inside the furnace at the same time as the furnace is shut down. Then, a heating coil (not shown) installed outside the furnace raises the processing temperature inside the furnace to 30°C.
Heat treatment such as diffusion is performed at 0°C to 1200°C. At this time, the processing temperature is measured from the outside using a thermocouple 7 installed inside the furnace, and heat processing such as diffusion is performed under appropriate processing conditions. In the above heat treatment, the semiconductor wafer 14 is inserted into and pulled out of the furnace while the furnace is heated. The air thermally expands and a pressure of about 5 Kv is applied, but the pressurized air passes through the pressure relief tube 1 provided in the lid part 2.
Since it is designed to be able to penetrate the atmosphere through 3, dangers due to thermal expansion can be prevented.

In a heat treatment furnace with such a structure, by attaching the lid 2 to the opening at one end of the furnace, the jig operating rod 8 and thermocouple 7, which are integrated with the lid 2, can be inserted into the furnace at the same time. The installation of the lid 2, the insertion of the processing jig 6 into the furnace, and the measurement of the processing temperature can be performed simultaneously in one operation.On the other hand, if the lid 2 is removed from one end of the furnace, the processing jig 6 can be removed at the same time. 6 and thermocouple 7 can be drawn out, making heat treatment operations easier.

Embodiment FIG. 2 shows another embodiment of the present invention, in which the lid, the jig operating rod, and the thermocouple are integrated so that the thermocouple is inside the jig operating rod. be.

5 is SiC or SiO for loading and unloading the processing jig 6;
This jig operating rod consists of two parts, and a thermocouple 7 for measuring the temperature inside the furnace is built inside this rod.

In this case, since the jig operating rod 5 is mechanically reinforced by the thermocouple 7 contained therein, deformation of the jig operating rod 8 due to heat can be avoided. In addition, in this embodiment, the jig operating rod 5
has a universal joint structure in which the L-shaped hanging tool 10 at the tip can be bent at any angle with respect to its axis, and when the processing jig 6 is inserted or removed,
Even if the inner wall of the furnace is slightly deformed, an L-shaped hanger 10 is attached to it.
is now able to follow.

Therefore, the processing jig 6 will not come off the L-shaped hanging fixture 10. Embodiment 1 FIG. 3 shows another embodiment of the present invention, in which a thermocouple is integrated with a lid that closes one end of an open furnace.

Reference numeral 7 denotes a thermocouple for measuring the temperature inside the furnace, and is attached to the inside of the lid part 2 at approximately the center.

In this case, since the thermocouple 7 is attached to the center of the lid, the lid can be closed from any angle without determining the vertical position of the lid.

In this case, a jig operating rod 5 for loading and unloading the processing jig 6 is provided separately. In a heat treatment furnace in which the lid part 2 and thermocouple 7 are integrated, the treatment temperature can usually be measured at any time without having to open the lid each time, and can be measured as needed. When removing the lid part 2, the thermocouple 7 can be pulled out from the furnace at the same time, and the processing jig 6
It does not get in the way of loading and unloading operations.

Embodiment FIGS. 4 and 5 show another embodiment of the present invention, in which a lid for closing an opening at one end of a furnace and a jig operating rod are integrated.

The jig operating rod 5 is attached to a lid 2 that closes one end opening of the furnace, and the jig operating rod 5 and the lid 2 are integrated.

A jig operating rod 5 that is integrated with the lid 2 has a universal joint structure near the lid, and an F-key shaped hook 10 is attached to its tip. The hook 10, which is supported by the hook 15 and has an F-shaped key shape at its tip, can move in large increments.

In this case, even if the lower surface of the furnace inner wall is uneven, the jig operating rod 5
Since the tip of the handle moves in a large circular motion, the processing jig 6 will not come off the F-key shaped hook 10, and since the jig operating rod 5 and the lid part 2 are integrated, The operation of putting in and taking out the processing jig 6 and the operation of opening and closing the furnace can be performed simultaneously, and the operation of putting in and taking out the processing jig 6 becomes extremely simple.

Note that FIG. 4 shows a device in which a foot portion 9 is provided on the lower side of the jig operating rod 5 with a universal joint structure to support it auxiliarily, and FIG. Shown is one that is directly attached with a universal joint structure.

The present invention is not limited to the above embodiments, and its structure can be changed as necessary, and can be applied to a wide range of applications, including not only diffusion furnaces but also vapor phase chemical growth furnaces, thermal oxidation furnaces, and other heat treatment furnaces. It is available.

According to the present invention as described in the embodiments above, the lid and other operating tools can be connected to each other, such as the lid, the jig operating rod and the thermocouple, the lid and the thermocouple, and the lid and the jig operating rod. Because it is integrated, loading and unloading the processing jig and measuring the processing temperature can be done at the same time as the lid attachment operation, making it extremely easy to perform operations inside the furnace such as loading and unloading the processing jig and measuring the processing temperature. It is something that can be done. In the case of Examples, . . . , a thermocouple is usually provided in the furnace, so that the treatment temperature can be measured at any time, and the heat treatment can be performed under appropriate conditions. According to the present invention, since the inside of the lid of the hollow tube body is filled with a heat insulating material such as quartz wool or alumina wool, heat is not transmitted to the outside of the furnace and there is extremely little risk of opening or closing the lid. Heat loss from the furnace is also extremely low because the insulation blocks secondary radiation.

Further, according to the present invention, various remarkable effects such as a reduction in the number of times the lid is opened and closed due to the internal operation of the furnace being performed at the same time as the closing and closing of the furnace, and a reduction in heat loss due to this are achieved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one embodiment of the invention, and FIGS. 2 to 5 are sectional views showing essential parts of other embodiments of the invention. 1. Furnace body, 2. Lid, 3. Hollow tube body, 4.
...Insulating material, 5.Jig operating rod, 6.Processing jig,
7... Thermocouple, 8... Main shaft, 9... Foot, 10
... Hanging fixture, 11... Conductor, 12... Handle, 13.
...Pressure relief tube, 14...Semiconductor wafer...15...
・Guide support part.

Claims (1)

[Claims] 1. A furnace body, a jig support, a lid movable at the same time as the jig support, and a
A heat treatment furnace characterized by having a pressure relief pipe for exhausting expanding air.