JPH025518A - Vapor growth device - Google Patents

Abstract

PURPOSE:To enhance the substantial rate of operation as well as the high quality production of the device by a method wherein an automatic control system of the whole operations of a temperature measurement means capable of measuring two or more positions in a high-frequency induction heating coil susceptor with an airtight vessel, a susceptor material gas feed system and an exhaust system, an automatic coil position adjustment mechanism. CONSTITUTION:The temperature distribution in a susceptor 3 is measured by six radiation thermometers 7 located in the diameter direction of the susceptor 3 from the gaps between high-frequency induction coils 5 through a quartz made coil cover 10 below the susceptor 3 subjected to less dirt and blur due to the reaction from material gas etc. One of the six radiation thermometers 7 is for measuring the reference temperature of the susceptor 3 as well as to control the output from a high-frequency oscillator so that the coil 5 immediately below the susceptor 3 detected to be at lower temperature by the reference thermometer 7 may be shifted nearer to the susceptor 3 in proper value by an automatic lifting mechanism 4. Furthermore, the coil 5 detected to be at higher temperature can be shifted farther to the susceptor 3 in proper value so that the susceptor reacting region may be evenly controlled at specified temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a semiconductor wafer vapor phase growth apparatus, and more particularly to a silicon epitaxial growth apparatus.

[Conventional technology]

Conventionally, this type of vapor phase growth apparatus has a rotatable susceptor installed in a stainless steel bell jar or quartz bell jar, as shown in Figure 3, on which a semiconductor wafer is placed and heated by a high-frequency induction heating coil. The structure is such that a desired thin film is grown in a vapor phase on a semiconductor wafer by supplying a raw material gas to the reaction region in the bell jar from a raw material gas supply system, and the gas in the bell jar is exhausted from an exhaust system. In order to deposit a highly uniform thin film with few crystal defects on each semiconductor wafer, it is important to minimize temperature variations in the reaction area within the susceptor, so that workers can safely and easily touch the high-frequency induction heating coil when adjusting the temperature. The equipment had to be shut down, shut down, and dismantled to ensure that it could be carried out.

Generally, the positional relationship between the coil and susceptor was adjusted by moving the coil closer to the susceptor in areas where the temperature was low, and moving the coil closer to the susceptor in areas where the temperature was high, thereby achieving temperature uniformity in the reaction area within the susceptor.

[Problem to be solved by the invention]

In order to deposit a thin film with good uniformity without crystal defects on all of the multiple semiconductor wafers placed on the susceptor,
Temperature uniformity of the reaction area within the susceptor is important. In the conventional vapor phase growth apparatus mentioned above, the temperature distribution can be measured by an operator looking at the film thickness variation and crystallinity of the semiconductor wafer after film formation, or by using a radiation thermometer through the bell jar viewing window. The temperature inside the susceptor was measured by changing the slope of the susceptor. Then, when adjusting the temperature, stop and dismantle the device so that the high-frequency induction heating coil can be accessed safely and easily, and remove the fixing jig of the coil support plate. After cleaning the quartz, or replacing the susceptor, adjust the positional relationship between the coil and the susceptor to separate it from the susceptor.
The process was continued until the film quality of all semiconductor wafers on the susceptor became uniform. Therefore, even if temperature distribution variations occur in the reaction region within the susceptor during operation of the apparatus, there is no quick and accurate means for measuring and correcting them, and product defects are often detected after they have occurred. Another drawback is that the actual operating time of the equipment is significantly reduced due to temperature adjustment work, which poses a serious problem in terms of long-term stable operation of the equipment and improvement of product quality.

[Differences between the invention and the prior art]

In contrast to the above-mentioned conventional vapor phase growth apparatus, the present invention uses a susceptor at two or more locations, and when measuring temperature through quartz using a radiation thermometer, for example, a stable method with less clouding due to reactions of raw material gases is provided. It measures the temperature distribution variation in the reaction area within the susceptor. Then, based on this information, the automatic high-frequency induction heating coil position adjustment mechanism automatically adjusts the position of the susceptor and coil by moving the coil closer to the susceptor in low-temperature areas and moving it away from high-temperature areas. The huge amount of time and effort that was previously spent on setting temperature conditions is no longer necessary, and it becomes possible to quickly and accurately adjust the temperature. Therefore, the present invention has the difference that the temperature uniformity in the reaction region is improved and it is possible to form a high-quality film with less crystal defects and less variation in film quality.

[Means to solve the problem]

The vapor phase growth apparatus of the present invention automatically controls the entire operation of the airtight container, the susceptor raw material gas supply system, the exhaust system, the high-frequency induction heating coil with an automatic coil position adjustment mechanism, and the temperature measurement means capable of measuring two or more locations inside the susceptor. We have a system.

〔Example〕

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

A plurality of semiconductor wafers 6 are placed on a rotatable disk-shaped carbon susceptor 3 provided in a stainless steel bell jar 1 and a quartz bell jar 2, and a high frequency induction heating coil 5 with an automatic vertical movement mechanism 4 at the bottom of the susceptor 3 is installed. to the desired temperature. Then, the raw material gas is supplied from the raw material gas supply nozzle 8 to the reaction area in the bell jar 1, 2, and the semiconductor wafer 6 is
A desired thin film is grown in a vapor phase thereon, and the gas in the bell jars 1 and 2 is exhausted from the exhaust system. The temperature distribution inside the susceptor 3 is measured by six radiation thermometers 7 at six points in the diametrical direction of the susceptor 3 from the gap between the high-frequency induction heating coil 5 through the quartz coil cover 10 at the bottom of the susceptor 3, which is less contaminated and cloudy due to reactions of raw material gases, etc. Measure. One of the six radiation thermometers 7 is used for standard measurement of the temperature of the susceptor 3 and for adjusting the output of the high frequency oscillator. coil 5
is moved closer to the appropriate value susceptor 3 by the automatic vertical movement mechanism 4. In addition, by separating the portions where the temperature is determined to be high by an appropriate value, the reaction region of the susceptor 3 can be controlled to a desired temperature with good uniformity. Therefore, according to this embodiment, the device can be stopped and
It is possible to quickly and accurately uniformize the temperature in the reaction area within the susceptor 3 without disassembling it, and it eliminates the need to manually adjust the positional relationship between the coil 5 and susceptor 3, thereby increasing product production. Can be allocated to time. Further, since the temperature variation in the reaction region within the susceptor is extremely reduced, it is possible to form a high quality film with few crystal defects and good film quality uniformity on all the semiconductor wafers 6 on the susceptor 3.

FIG. 2 is a longitudinal sectional view of Example 2 of the present invention.

The raw material gas is supplied from the raw material gas supply system to the semiconductor wafer 6 placed on the barrel-shaped susceptor 11 in the quartz bell jar 2' and heated by the high-frequency induction heating coil 5', and a desired thin film is grown in the vapor phase. The gas within ' is exhausted from the exhaust system. The temperature distribution inside the barrel-shaped susceptor 11 is precisely measured by a plurality of radiation thermometers 7 installed inside, and the automatic coil spacing mechanism 4' moves the coil 5' spacing to an appropriate value, so that generally low temperature areas are The distance between the coils 5' is narrowed and the high-temperature areas are widened to keep the temperature distribution inside the susceptor 11 in a uniform state at all times. In this embodiment, since the temperature uniformity of the plurality of semiconductor wafers 6 is improved, there is an advantage that it is possible to form a film with fewer crystal defects and film quality variations.

〔Effect of the invention〕

As explained above, in the present invention, when a susceptor is used to measure temperature at two or more locations, such as a radiation thermometer, when measuring through quartz, the susceptor is attached to a stable location where there is less clouding due to reaction of raw material gas, etc. Measure the temperature distribution in the reaction area within the susceptor. Then, based on this information, the high-frequency induction heating coil position automatic adjustment mechanism quickly and accurately adjusts the coil and susceptor positions, thereby achieving temperature uniformity in the reaction region within the susceptor. Therefore, in the past, workers had to stop and disassemble the equipment to safely and easily access the coil, remove the coil fixing jig, and adjust the positional relationship between the coil and susceptor. This eliminates the need for a huge amount of labor and time, and has the effect of increasing the actual operating rate of the equipment and producing high-quality products.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a vapor phase growth apparatus of the present invention, FIG. 2 is a longitudinal sectional view of a second embodiment, and FIG. 3 is a sectional view of a conventional vapor growth apparatus. 1... Stainless steel bell jar, 2...
・Quartz bell jar, 3...susceptor, 4.4'・
...Automatic coil vertical (interval) movement mechanism, 5...
...High frequency induction heating coil, 6...Semiconductor wafer, 7,7'...Radiation thermometer, 8...
... Raw material gas supply nozzle, 9 ... Coil support plate, 10 ... Coil cover 11 ... Barrel type susceptor, 12 ... Susceptor rotation mechanism,
13... Peep window

Claims (1)

[Claims] an airtight container, a susceptor installed in the airtight container on which a workpiece can be placed, a high-frequency induction heating coil serving as heating means for the susceptor, and a source gas supply for supplying the source gas into the airtight container. A vapor phase growth apparatus comprising a system and an exhaust system for exhausting gas in the airtight container, which has a means capable of measuring temperature at at least two points on the susceptor, and uses high-frequency A vapor phase growth apparatus characterized by having a mechanism that can automatically adjust the positional relationship between an induction heating coil and a susceptor.