JPH0763059B2 - Semiconductor manufacturing equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat treatment furnace for thermal oxidation, thermal diffusion, annealing, etc., in which a gas must be introduced from the outside in a semiconductor manufacturing process to maintain a uniform temperature region. It is a thing.

[Prior Art] Conventionally, as shown in FIG. 2, a gas is introduced from a gas introduction port of a thermal diffusion furnace, and a semiconductor substrate holder 4 is inserted into a uniform temperature region to perform various heat treatments such as thermal oxidation, thermal diffusion and annealing. Has been carried out.

[Problems to be Solved by the Invention] However, in the conventional thermal diffusion furnace, before inserting the semiconductor substrate 5 to obtain a uniform temperature region, the same gas (5 to 20 liters / minute) as the heat treatment of the semiconductor substrate is used. ) Was introduced into the furnace core tube 2 from the gas inlet 1 to measure the temperature, and a uniform temperature region was secured. Therefore, when the semiconductor substrate 5 is inserted after that, the semiconductor substrate closest to the gas inlet has a uniform temperature. There is a problem that the gas that has not reached the temperature of the region is dammed up, the temperature distribution that should be a uniform temperature region in the subsequent furnace core tube is not constant, and uniform heat treatment for each semiconductor substrate is hindered.

Therefore, in order to solve such a conventional problem, the present invention secures a uniform temperature region without inserting the semiconductor substrate, and then the temperature of the uniform temperature region changes even if the semiconductor substrate is inserted and heat treatment is performed. It is an object of the present invention to provide a thermal diffusion furnace in which a semiconductor substrate can be uniformly heat-treated.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention has a heater as a heating source arranged outside the furnace core tube, and introduces gas into the furnace core tube at a predetermined temperature. In a semiconductor manufacturing apparatus for heat-treating a semiconductor substrate, there is a preheating region for preheating the introduced gas before a treatment region of a predetermined temperature, and the preheating region is arranged so as to be entirely covered by the heater, and gas is introduced. And the furnace core tube are provided independently of each other, and the preheating region has an outer diameter larger than the diameter of the semiconductor substrate and smaller than the furnace core tube inner diameter, and opens toward the gas introduction port side. A bottomed portion having a cylindrical portion is arranged, and the gas is introduced into the processing region by passing the gas through a gap between the furnace core tube and the bottomed material.

Embodiments Embodiments of the present invention will be described below with reference to the drawings. First, FIGS. 1, 3, and 4 which are reference diagrams for supplementarily explaining the embodiment of the present invention will be described. FIG. 1 is a sectional view of an example thereof. As shown in FIG. 1, the gas introduced from the gas introduction port 1 from the outside of the thermal diffusion furnace reaches the uniform temperature region where the semiconductor substrate 5 standing on the semiconductor holder 4 is inserted and reaches the uniform temperature region. Since it reaches 6 and the straight path is blocked, it takes time to reach the semiconductor substrate, during which the gas is warmed. The gas interference plate is welded to and integrated with the furnace core tube 2. 3 is a heater for creating a uniform temperature region.

FIG. 3 is a sectional view of another example for explaining the present invention.
FIG. 3 is an improved version of FIG. 1, in which an auxiliary gas interference plate 7 is provided in front of the gas interference plate in order to further increase the heat transfer efficiency. FIG. 4 is a sectional view of still another example for explaining the present invention. In this example, the pipe from the gas inlet is extended to the inside of the furnace core tube, and in order to efficiently obtain the temperature rise of the introduced gas, the length is made into a spiral shape, and the gas inlet is not directed to the semiconductor substrate. It is more efficient.

In the examples described above with reference to FIGS. 1, 3, and 4, it is possible to hold the semiconductor substrate to be heat-treated in a predetermined temperature region. However, it is still insufficient in terms of handleability.

Here, FIG. 6 is also a reference example for explaining the present invention. FIG. 6 shows a semiconductor holder 4 which is a holding member on which the semiconductor substrate 5 is mounted, and a gas interference plate 6 which is gas flow path control means.
Can also be held or directly welded. Although it was improved in handleability, it is not sufficient in heating gas.

The present invention is a further improvement of these, in which the workability of maintenance such as repair and cleaning is improved while maintaining the uniformity of temperature distribution.

FIG. 5 is a sectional view of an embodiment of the present invention. In this example,
A gas interference part, which is a gas flow path control means, is provided on the gas introduction part side of the processing region of the semiconductor substrate independently without being integrated with the gas introduction part or the furnace core tube 2 where the semiconductor substrate 5 is heat-treated. It was formed.

This interference part is provided on the gas interference part side, which is a gas flow path control plate, and on the gas introduction part side of the gas interference plate.
And a preheating region that serves as a gas introduction chamber for temporarily retaining the gas introduced from.

The gas interference portion is configured to be movable with respect to the furnace core tube 2 and prevents the furnace core tube 2 from being inadvertently contacted.
Since it is formed smaller than the inner diameter of, it has the advantage of being easy to repair and clean. Further, as shown in FIG. 6, since a bottomed material having a cylindrical portion is installed as a preheating region to serve as a gas introduction chamber in which the gas is temporarily retained, the introduced gas can be sufficiently heated, and the temperature distribution can be made uniform. It is possible to maintain the sex.

As described above, the invention described in the present embodiment has a structure in which a narrow gap is provided between the furnace core tube to be the furnace body and the flow path control means, so that the furnace core tube heated by the heater and the flow The gas gradually flows through the narrow gap between the passage control means and the heater, the heated furnace core tube, and the flow passage control means to efficiently perform heat conversion to the gas. When the heater is heated from the outer peripheral portion of the furnace core tube, the temperature tends to be higher in the peripheral portion near the heater than in the central portion of the furnace core tube. Therefore, as in the embodiment, by introducing a gas having a relatively low temperature through the narrow gap between the furnace body close to the heater and the flow path control means, the introduced gas is warmed and the temperature distribution in the furnace core tube is improved. It can be made uniform.

Further, since the diameter of the introduced gas is larger than that of the semiconductor substrate mounted on the holding member, the introduced gas does not directly contact the semiconductor substrate. By adopting such a configuration, even if the introduced gas is introduced into the furnace core tube without being heated to the temperature inside the furnace core tube, the temperature distribution in the peripheral portion of the semiconductor substrate is reduced because it does not directly contact the semiconductor substrate. There is nothing to find out.

[Effects of the Invention] As described above, the present invention provides a semiconductor device for heat-treating a semiconductor substrate with a simple structure including a means for warming the introduced gas between a uniform temperature region and a gas inlet from the outside. This has the effect of maintaining a uniform temperature region regardless of the presence or absence of a semiconductor substrate. Therefore, the temperature uniformity of the heat treatment of the semiconductor substrate can be maintained, the electric characteristics of the integrated circuit can be stabilized, the yield can be improved, and the semiconductor substrate can be processed in a large amount, which leads to the cost reduction of the integrated circuit device. .

Further, as shown in FIG. 5 and FIG. 6, since the gas flow path control means constituting the means for warming the introduced gas is formed independently of the gas introduction part and the furnace core tube, it is possible to repair or clean the gas. Maintenance work can be performed easily.

Further, since the gas flow path control means is formed smaller than the inner diameter of the furnace core tube, when the gas flow path control means is taken in and out during maintenance, there is little risk of scratches, chips, cracks, etc., and the maintainability is excellent. A highly reliable semiconductor device can be obtained.

Further, as shown in FIG. 5, by configuring the gas flow path control means with the gas flow path control plate and the gas introduction chamber, the above effects can be brought about with an extremely simple structure.

Further, according to the present invention, since the semiconductor substrate is formed larger than the semiconductor substrate mounted on the holding member, the introduced gas does not directly contact the semiconductor substrate. By adopting such a configuration, even if the introduced gas is introduced into the furnace body without being sufficiently heated to the temperature inside the furnace core tube, it is gradually supplied from the inner peripheral portion of the furnace core tube. Since the temperature distribution is not disturbed around the substrate, a particularly reliable semiconductor device can be provided.

[Brief description of drawings]

1, FIG. 3, FIG. 4 and FIG. 6 are reference views for supplementarily explaining the embodiment of the present invention, and FIG. 2 is a cross-sectional view of a thermal diffusion furnace which is a conventional semiconductor manufacturing apparatus. FIG. 5 is a sectional view showing an embodiment of means for warming the introduced gas according to the present invention. 1 ... Gas inlet 2 ... Furnace core tube 3 ... Thermal diffusion furnace heater 4 ... Semiconductor substrate holder 5 ... Semiconductor substrate 6 ... Gas interference plate 7 ... Auxiliary gas interference plate 8 ... Heater

Claims (1)

[Claims] 1. A semiconductor manufacturing apparatus in which a heater, which is a heating source, is arranged outside a furnace core tube, and a gas is introduced into the furnace core tube to heat-treat a semiconductor substrate at a predetermined temperature. Has a preheating region that is preheated before the treatment region, the preheating region is arranged so as to be entirely covered by the heater, and is provided independently of the gas introduction unit and the furnace core tube, and the preheating region is also provided. A bottomed object having an outer diameter larger than the diameter of the semiconductor substrate and smaller than the inner diameter of the furnace core tube, and having a cylindrical portion opening to the gas introduction port side is arranged. A semiconductor manufacturing apparatus, wherein the gas is introduced into the processing region by passing the gas through a gap between the bottomed material.