JPS627685B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has a triple quartz bell gear, the inner surface of the outer quartz bell gear is uniformly coated with a metal film with high reflection efficiency, and the inner surface is heated by a heater attached to the inner side of the outer quartz bell gear. This invention relates to a vertical vapor phase growth apparatus that incorporates a mechanism for directly heating a semiconductor wafer placed on a heating plate in a bell gear, and indirectly by heating rays reflected by a metal film.

FIGS. 1a and 1b are a perspective view and an AA sectional view of an example of a conventional horizontal vapor phase growth apparatus equipped with a heater.

In FIGS. 1a and 1b, a plurality of quartz heaters 32 are arranged horizontally above and below the outside of a quartz reaction tube 31 placed in a horizontal position, and are placed diagonally inside the reaction tube 31. The plurality of semiconductor wafers 30 placed on the heating plate 33 are heated by the heater 3.
2 is heated to a high temperature by the energization, and contacts the high temperature reaction gas 18 flowing in from the wide opening of the reaction tube 31, and the reaction gas itself or a desired substance is produced by a chemical reaction between the reaction gas and the wafer. is grown on the wafer 30 in a vapor phase.

FIG. 2 is a cross-sectional view of an example of a conventional vertical vapor phase growth apparatus, in which a quartz bell gear 34 is placed through the center of a base plate 35, and a reaction gas introduction pipe 36 and the outside of the introduction pipe 36 are exposed. A surrounding heating plate rotating shaft 37 is provided, and a semiconductor wafer 30 is placed on a heating plate 38 supported by the heating plate rotating shaft 37. The wafer 30 rotates as the heating plate 38 rotates, and the wafer 30 rotates under the heating plate 38. The carbon heating plate is heated by energization of a spiral-shaped high-frequency coil 39 provided in the wafer 39 , which is introduced into the wafer 30 heated by the high-temperature heating plate 38 through the reaction gas introduction pipe 36 and exhausted through the exhaust pipe 40 . The reaction gas 18 comes into contact with the wafer 30, and a desired substance corresponding to the reaction gas 18 is vapor-phase grown on the wafer 30.

Among the conventional horizontal and vertical vapor phase growth apparatuses explained above, the resistance heater heating shown in Fig. 1 is due to variations in the resistance of each heater, heat generation failure of individual heating heaters, and the heating shown in Fig. 2. In high-frequency heating, it is difficult to make the temperature distribution on the heating plate uniform due to the internal diameter of the windings of the high-frequency coil, the winding spacing, and the mutual positional relationship with respect to the heating plate. Therefore, the temperature distribution of the semiconductor wafer also becomes uneven. However, it has been difficult to make the grown film thickness and resistivity uniform within a semiconductor wafer, between semiconductor wafers, and between vapor phase growth processes.

In addition, high-frequency heating requires a heating power of about 100 kilowatts, while heating with a heater requires only a few tens of kilowatts, but on the other hand, the heater has a large temperature capacity, so it is difficult to perform rapid heating and cooling. He was efficient.

An object of the present invention is to provide a vapor phase growth apparatus that consumes relatively little power, is capable of rapid heating and cooling, and performs vapor phase growth with less variation in film thickness and resistivity. be.

The vapor phase growth apparatus of the present invention comprises an inner bell gear, a central bell gear placed outside the inner bell gear, and a metal film placed outside the central bell gear and coated with a metal film with high reflection efficiency on the inner surface. A cooling plate is provided between an outer bell jar, a growth substrate mounting table having a heating plate function (hereinafter referred to as a wafer heating plate) provided in the inner bell gear, and the inner bell gear and the center bell gear. a heater provided between the central bell gear and the outer bell gear; a reaction gas introduction pipe for introducing a reaction gas into the inner bell gear; It has a configuration including an exhaust pipe for exhausting gas from inside the bell jar.

According to the present invention, the semiconductor wafer placed on the rotating heating plate in the inner bell gear is heated directly and heated to the inner surface of the outer bell gear by the heater provided between the central bell gear and the outer bell gear. Since the heat rays reflected by the deposited metal film are heated tangentially, the temperature rises quickly and has a uniform temperature distribution, making it possible to achieve efficient heating with low power consumption. A device is obtained.

Next, the present invention will be explained by examples.

FIG. 3 is a sectional view of one embodiment of the present invention. In FIG. 3, the inner bell gear 1 is placed on the base plate 6 via the rubber ring 8 for sealing, and the lower flange of the inner bell gear 1 is
It is locked by a fixing claw 7 and is completely airtightly fixed to the base plate 6. A flat ring 10 is attached to the upper side of the outer support cylinder 9 at the base of the inner bell gear 1.
An outer bell gear 3 is attached to the center bell gear 2 and the outside thereof via a heater 4, and a heater 4 is installed between the center bell gear 2 and the outer bell gear 3. is provided with a metal film with high reflection efficiency, for example, a gold coating 5. A cooling gas inlet 11 is provided at one location on the outer periphery of the support cylinder 9, and a discharge pipe 12 thereof is provided at the top of the central bell gear 2, and a part of the outer periphery of the discharge pipe is surrounded by a water cooling device 13. It is.

The above base plate 6, inner bell gear 1, center bell gear 2, outer bell gear 3,
The bell gear assembly 14, which is integral with the supporting cylinder 9 and the like, is airtightly placed on the main body base plate 20 via a sealing rubber ring 19, and is separated from the main body base plate 20 by a drive device 15. It is said that it is possible to ascend. A rotating shaft 22 directly connected to the wafer heating plate 21 passes through a substantially central position of the main body base plate 20 , and the rotating shaft is rotationally driven by a motor 23 .

Next, a procedure for attaching the semiconductor wafer 30 will be described. The bell gear assembly 14 described above,
The heating plate 21 is raised by the quartz reaction tube base plate vertical drive device 15 attached to the main body base plate 20, and the reaction chamber in the inner bell jar 1 is opened to the atmosphere, and the heating plate 21 is directly connected to the heating plate rotation shaft 22.
A semiconductor wafer 30 is placed on top. Subsequently, a rubber ring 19 for sealing between the bell gear assembly 14 and the main body base plate is attached to a rubber ring groove cut in the main body base plate 20, and the bell gear assembly 14 is lowered to completely seal tightly with the main body base plate 20.

Next, in order to perform vapor phase growth on the semiconductor wafer 30, the heating plate rotation shaft 22 is continuously rotated by the motor 23, and the reaction gas 18 is passed through the reaction gas inlet 16.
is collected from the reaction gas outlet 17. At the same time, a gas such as air or nitrogen is pressurized through the cooling gas inlet 11 and discharged to the outside through the cooling gas outlet 12 which is cooled by the water cooling device 13.
A heating heater 4 connected to a separately installed heater heating power source generates heat and heats the semiconductor wafer 30.
A substance that responds quickly to the reaction gas is grown in a vapor phase on top.

An automatic temperature controller is attached to the heater heating power source, and the temperature information measured at the temperature measurement terminal 24 protruding inside the inner bell jar 1 is fed back, and the temperature is automatically controlled to a preset temperature. It has a structure that allows for When using air or nitrogen as the cooling gas, if you use the gas that has been cooled to a temperature lower than room temperature by passing it through a refrigerator or heat exchanger in advance, it is possible to cool the heater and the inner, central, and outer quartz bell jars. can be cooled more effectively, and the amount of vapor-grown film deposited on the inner surface of the upper inner bell gear 1 can be reduced as much as possible.

As explained above, according to the present invention, semiconductor wafers can be raised to a predetermined vapor phase growth temperature efficiently and uniformly in a short time with less power, and continuous automatic temperature control can be performed. It is possible to continuously obtain semiconductor wafers having vapor-phase grown films with uniform distribution of various properties such as film thickness and resistivity within the wafer and with good reproducibility.
Significant efficiency gains can be achieved.

[Brief explanation of the drawing]

Figures 1a and b are a perspective view and a sectional view taken along the line A-A of a conventional horizontal vapor growth apparatus, Figure 2 is a sectional view of an example of a conventional vertical vapor growth apparatus, and Figure 3 is the invention of the present invention. FIG. 2 is a cross-sectional view of one embodiment of the invention. 1...Inner bell gear, 2...Center bell gear, 3...Outer bell gear, 4...Heating heater,
5...Metal reflective film, 6...Base plate, 7...
... Locking claw, 8, 19 ... Rubber ring for sealing, 9
...Support cylinder, 10...Flat plate ring, 11...Cooling gas inlet, 12...Cooling gas discharge pipe, 13...
...Water cooling device, 14...Belgear assembly, 15...
Drive device, 16...Reaction gas introduction pipe, 17...Gas discharge pipe, 18...Reaction gas, 20...Main body base plate, 21...Wafer heating plate, 22...
Rotating shaft, 23...Motor, 24...Temperature measurement terminal, 30...Semiconductor wafer.

Claims (1)

[Claims] 1. an inner bell gear, a central bell gear located outside the inner bell gear, an outer bell gear located outside the central bell gear and having a metal film with high reflection efficiency coated on the inner surface; A growth substrate mounting table provided in the inner bell gear, a cooling means for flowing cooling gas between the inner bell gear and the center bell gear, and a cooling means provided between the center bell gear and the outer bell gear. A vapor phase growth method characterized in that the vapor phase growth method includes a heating heater, a reaction gas introduction pipe for introducing a reaction gas into the inner bell gear, and an exhaust pipe for discharging the gas from the inner bell gear. Device.