JPH08181082A - Vertical-type high-speed heat treatment device - Google Patents

Abstract

PURPOSE: To provide a vertical-type high-speed heat treatment device which is capable of thermally treating many substrates at a time at a high speed, restraining impurities contained in the treated substrate from diffusing, forming a shallow junction, and causing no oxidation to the surface of the substrates even if it is made to serve as a CVD device. CONSTITUTION: A semiconductor manufacturing vertical-type high-speed thermal treatment device is equipped with a resistance heater 4 which is provided with a heat insulator on its rear and provided to the outside of a reaction tube 10, wherein a treated substrate 1 placed inside the reaction tube 10 is thermally treated at high temperatures, another resistance heater 3 is provided between the reaction tube 10 and the resistance heater 4 separate from both of them, and the resistance heater's 3 and 4 are made to form thermal zones which are separately controlled in temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical rapid thermal processing apparatus for manufacturing semiconductors, and more specifically, it extremely shortens the time for processing a processed substrate at a high temperature, and moreover, allows a plurality of substrates to be processed once. The present invention relates to a vertical high-speed heat treatment apparatus capable of performing the above-mentioned processing.

[0002]

2. Description of the Related Art Conventionally, a vertical high-speed thermal processing apparatus for heat-treating a processed substrate at a high temperature makes the temperature of the substrate extremely fast by heating the lamp using an infrared lamp, and the single-wafer processing is performed. However, there is a problem in that the productivity cannot be increased due to the processing at 1, and the cost becomes high. Further, as shown in FIG. 6, a device in which a large number of substrates 1 are mounted on a boat 2 and heated by a resistance heating heater 19 from the outside of the reaction tube 10 has been known.

However, according to this method, even when the resistance heating heater 19 having an extremely high temperature raising / lowering characteristic is used, the temperature raising / lowering rate is at most about 100 ° C./min.
It cannot meet the demand for rapid thermal processing (RTP) for processing within a few minutes, and the time at high temperature becomes long, so that the diffusion of impurities in the processed substrate increases and the shallow junction even if annealing is performed. In addition to being impossible to form, there was a problem that slips (crystal defects) were generated on the processed substrate. Moreover, when this apparatus is applied to a CVD (Chemical Vapor Deposition) apparatus, the boat 2 on which the substrate 1 is mounted is attached to the reaction tube 1
There was a problem that the surface of the substrate 1 was oxidized when it was inserted into 0.

[0004]

SUMMARY OF THE INVENTION The present invention is intended to solve such a problem, in which a large number of substrates are heat-treated at a high speed at a time, diffusion of impurities in the processed substrates is reduced, and shallow bonding is performed. It is an object of the present invention to provide a vertical high-speed heat treatment apparatus which enables the formation of a substrate and does not oxidize the substrate surface even when the CVD apparatus is used.

[0005]

According to the structure of the present invention which meets the above object, a resistance heating heater having a heat insulating material on the back surface is provided outside the reaction tube, and the substrate to be processed in the reaction tube is heated at a high temperature. In a vertical high-speed heat treatment apparatus for manufacturing semiconductors for heat treatment, a resistance heating heater is disposed between the reaction tube and the resistance heating heater with a space between the resistance heating heater and the resistance heating heater. Is formed into a plurality of zones whose temperature can be controlled independently of each other.

[0006]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a vertical sectional view of a diffusion furnace showing an embodiment of the present invention, and FIG. 3 is a sectional view taken along the line AA ′ of FIG. Inside the reaction tube 10, a board on which a plurality of substrates (wafers) 1 are mounted is mounted.
To 2 is interior. An inner heater 3 and an outer heater 4 are cylindrically arranged on the outer periphery of the reaction tube 10. The inner heater 3 and the outer heater 4 use resistance heating heaters having a low heat capacity and excellent temperature rising / falling characteristics.
Reference numeral 20 in FIG. 4 indicates a cylindrical outer cylinder, but it is omitted in FIG.

The inner heater 3 is, as shown in FIG.
The heater wires 17 are wound around the pillar 14 formed of a heat-resistant material in the shape of a pipe at intervals and fixed at appropriate positions. By winding the heater wires 17 around the columns 14 at such intervals, it is possible to easily cool the heater wires 17 and avoid shortening the life of the heater wires 17. it can. FIG. 5 shows another example of the inner heater 3, in which a pipe-shaped support 14 is formed in a ring shape, and a large number of the support 14 are arranged in the up-down direction. An example is shown in which the heater wires 17 formed in a wave shape are fixed at intervals.

As described above, since the inner heater 3 is composed of the heater wire 17 and the support 14 and the heat insulating material is not fixed to the back surface thereof, the temperature raising / lowering characteristic is extremely good.
A large number of through holes 16 are bored in the pipe-like support 14, and cooling air is ejected from the through holes 16 so that the heater wire 17 can be rapidly cooled. As shown in FIGS. 1 and 4, the outer-heater 4 is formed in a cylindrical shape, and the heat insulating material 18 is fixed near the back surface. The inner heater 3 may be further interposed between the inner heater 3 and the outer heater 4, but this arrangement has no particular advantage. Inner Heater 3 and Outer Heater
The rotor 4 is divided into a plurality of zones that control the temperature independently, and thermocouple temperature sensors 5 and 6 are provided in each zone. An internal temperature measuring thermocouple sensor 7 is also arranged in the vicinity of the processing substrate 1 in the reaction tube 10.

When the reaction tube 10 is heated by the inner heater 3 and the outer heater 4, the internal temperature measuring thermocouple sensor 7 is used.
The output balance of each zone of the inner heater 3 and the outer heater 4 is made by using the thermocouple temperature sensors 5 and 6 so that the areas to be soaked at the same temperature increase rate. Is configured so that it can be controlled. As shown in FIG. 1, cooling air-introducing pipes 11 and 11 'are arranged at the lower ends of the inner heater 3 and the outer heater 4, and the cooling air is connected to the reaction pipe 10. The air is exhausted to the outside through the exhaust ducts 8 and 8'provided at the upper end through the inner heater 3 and the inner heater 3 and the outer heater 4.

[0010]

Next, the operation of the present invention constructed as above will be described. If necessary, an inert gas or the like is introduced from above as shown by the arrow in FIG. 1, and the boat 2 having the plurality of substrates 1 mounted thereon is raised at a relatively low temperature of 600 to 700 ° C. When it is introduced into the reaction tube 10 and reaches the processing position shown in FIG. 1, the inner heater 3 and the outer heater 4 are set to full power, and the temperature is raised at a temperature of 200 ° C./min for 90 minutes at a stroke.
The processing temperature is raised to 0 ° C. or higher (usually 900 to 1200 ° C. at the temperature measured by the thermocouple sensor for measuring internal temperature). At this time, each of the inner heater 3 and the outer heater 4 is controlled by the inner temperature measuring thermocouple sensor 7 installed near the processing substrate 1 so that the regions to be soaked have the same temperature rising rate. The output balance of each zone of the inner heater 3 and the outer heater 4 is controlled by the signals of the thermocouple sensors 5 and 6 arranged in the zone.

After the heat treatment is completed, the outputs of the inner heater 3 and the outer heater 4 are cut off, and the air is introduced from the air introduction pipes 11 and 11 'arranged at the lower ends of the heaters 3 and 4, respectively. The cooling air is introduced from the holes of the support 14 of the inner heater 3 at the same time, the cooling air is raised as shown by the arrow in FIG. 1, and the hot air is exhausted at the upper end. Duct 8,8 '
To the outside. By cooling in this manner, the processed substrate is cooled at a temperature lowering rate of, for example, about 100 ° C./min.
The temperature can be lowered to a low temperature of 600 to 700 ° C at a stroke. Then, the boat 2 is lowered to the outside of the reaction tube 10 and cooled to room temperature, and the treatment is completed.

By performing the above-mentioned treatment, the time when the substrate is kept at 900 ° C. or higher can be set to several minutes, so that the productivity can be improved and at the same time,
It is possible to obtain a product in which the diffusion of impurities in the processed substrate is reduced and the required characteristics of the semiconductor to be manufactured are sufficiently satisfied. Figure 2
It is a longitudinal section showing an example of the present invention in the case of a low pressure CVD apparatus. In the case of a low pressure CVD apparatus, the boat 2 is raised at a temperature of about 500 ° C. at which a natural oxide film is not formed, is inserted into the reaction tube 10, the hatch 13 is closed, and an inert gas or the like is drawn from below by an arrow. It can be carried out in the same manner as described above, except for introducing and vacuuming as shown. In this way, the film formation process can be performed in a similar manner in a short time, and since the film formation is performed in a high temperature state after evacuation, a film formation process in which a natural oxide film is not formed can be performed. .

[0013]

[Effects] According to the present invention, since the temperature rising / falling time of the resistance heating heater can be extremely shortened, the time for which the processing substrate is kept in a high temperature state can be shortened, so that the diffusion of impurities in the processing substrate can be reduced, Even if annealing is performed, a shallow junction can be formed, and a large number of substrates can be processed in a short time as compared with a conventional apparatus such as a lamp annealing apparatus, so that the productivity is dramatically increased. improves. Moreover, since the temperature rise and fall is not as rapid as in the lamp anneal device, the substrate (wafer)
It is possible to prevent the occurrence of (c) slip. Furthermore,
Even when the low pressure CVD apparatus is used, the boat can be inserted into the reaction tube without growing the natural oxide film and the film forming process can be performed, which is particularly useful for forming the polysilicon or the nitride film.

[0014]

[Brief description of drawings]

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

FIG. 2 is a vertical sectional view showing another embodiment of the present invention.

FIG. 3 is a sectional view taken along the line AA ′ in FIG.

FIG. 4 is an enlarged detailed front view of the heater used in the present invention.

FIG. 5 is an enlarged detailed front view of another heater used in the present invention.

FIG. 6 is a vertical sectional view of a conventional diffusion furnace.

[Explanation of symbols]

1 substrate (wafer) 2 boat 3 inner resistance heating heater (inner)
Heater 4 Outside resistance heating heater (outer)
Heater) 5, 6, 7 Thermocouple temperature sensor 10 Reaction tube

Claims (5)

[Claims] 1. A vertical high-speed heat treatment apparatus for semiconductor manufacturing, wherein a resistance heating heater having a heat insulating material on its back surface is provided outside a reaction tube, and a processed substrate in the reaction tube is heat-treated at a high temperature. A resistance heating heater is arranged with a space between the reaction tube and the resistance heating heater, and both resistance heating heaters are:
A vertical high-speed heat treatment apparatus, characterized in that it is formed into a plurality of zones whose temperatures can be controlled independently. 2. The vertical high-speed heat treatment apparatus according to claim 1, wherein the resistance heating heater on the inner side is formed by fixing heat-resistant support columns with heater element wires at intervals. 3. The vertical rapid thermal processing apparatus according to claim 2, wherein a large number of holes for ejecting cooling air are formed in the support column. 4. In order to exhaust heat between the reaction tube and the resistance heating heater, cooling air is introduced from the lower part and exhausted from an upper exhaust duct. Vertical high-speed heat treatment equipment. 5. A thermocouple temperature sensor is arranged in each zone of the reaction tube and a plurality of zones of the resistance heating heater which can be independently temperature controlled. Vertical high-speed heat treatment apparatus described in.