JPS5926598Y2 - semiconductor manufacturing equipment - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a semiconductor manufacturing apparatus suitable for forming an epitaxial growth layer on a semiconductor wafer.

In semiconductor devices such as epitaxial transistors and integrated circuit devices, there is a process of forming an epitaxial growth layer on a semiconductor wafer. Conventionally, when forming this epitaxial growth layer, an apparatus such as the one shown in Figure 1 is used. .

In the figure, reference numeral 1 denotes a cylindrical transparent quartz furnace core tube, which has a semiconductor wafer inlet/outlet 2 at one end, a gas inlet 3 for introducing a carrier gas, a silicon compound gas, and a dopant gas in the vicinity thereof; It has a gas outlet 4 at the end.

A high-frequency heating coil 5 as a heating means is arranged around the furnace core tube 1, and the entrance/exit 2 is closed with a lid 6 made of stainless steel.

A wafer support means 8 on which a number of semiconductor wafers 7 are placed is inserted into the furnace core tube 1 .

This wafer support means 8 is composed of a support stand 9 made of quartz and a susceptor 10 placed thereon so that its upper surface is inclined with respect to the gas flow direction. is placed.

The susceptor 10 is a graphite plate C whose entire surface is coated with silicon carbide (SiC), and the high frequency heating coil 7
The graphite plate is heated by high frequency induction, thereby heating the semiconductor wafer 7 on the susceptor 10 to a predetermined temperature.

In this configuration, while introducing nitrogen gas etc. from the gas inlet 3, the high frequency heating coil 6 is energized to heat the semiconductor wafer 7 to a predetermined temperature, and then silicon compound gas and dopant gas are introduced to perform thermal decomposition or reduction. Then, an epitaxial growth layer having a predetermined resistivity is formed on the semiconductor wafer 7.

Here, since the properties and growth rate of the epitaxially grown layer change depending on the temperature of the semiconductor wafer 7, it is necessary to control the temperature of the semiconductor wafer 7.

Conventionally, as shown in FIG. 1, the temperature control method has generally been to measure the temperature from the pitch portion of the high-frequency heating coil 5 through the tube wall of the reactor core tube 1 using an optical pyrometer 11.

However, with this method, as the epitaxial growth progresses, silicon also adheres to the inner wall surface of the reactor core tube 1, and since the temperature is measured through this silicon film, there is a problem in that the measurement accuracy decreases. .

Therefore, the main purpose of this invention is to provide a semiconductor manufacturing apparatus that can measure temperature with high accuracy.

To summarize, this invention is characterized in that a protrusion for temperature measurement is provided on the side surface of the susceptor of the wafer support means, and at least a portion of the lid is formed of a transparent member.

The above objects and other objects and features of the present invention will become more apparent from the following detailed description with reference to the drawings.

FIG. 2 shows a longitudinal cross-sectional view of a manufacturing apparatus according to an embodiment of the invention, FIG. 3 shows a cross-sectional view thereof, and FIG. 4 shows a front view of the lid body.

As is clear from FIGS. 2 to 4, in FIGS. 2 and 3, only the lid body is shown in FIG. The figure shows a cross-sectional view taken along line Ill-III in FIG.

Since most parts in the figure are the same as those in FIG. 1, the same reference numerals are given to the same or corresponding parts as in FIG. 1, and the explanation thereof will be omitted.

The difference from FIG. 1 is that the susceptor 10 has protrusions 10a for temperature measurement at asymmetric positions on both side surfaces.

10b, and transparent glass windows 6a and 6b are hermetically sealed at positions corresponding to the protrusions 10a and 10b of the susceptor 10 on the stainless steel lid 6. .

Even in such a configuration, since it is basically the same as that shown in FIG. 1, an epitaxial growth layer can be formed on the semiconductor wafer 7 in exactly the same manner as the conventional apparatus shown in FIG.

Next, to explain how to measure the temperature, as shown in FIGS. 2 and 3, the transparent glass window 6 is
The temperature of the protrusions 10a, 10b of the susceptor 10 inside the core tube 1 is measured by optical pyrometers 11a, 11 through a, 6b.
1b.

Next, by the temperature measurement method using the conventional device and the device of this invention, the output of the high-frequency heating coil 5, the amount of gas introduced, etc. are adjusted so that the initial measurement temperature is 1200°C, and the state is maintained. When epitaxial growth was performed continuously, the results shown in FIG. 5 were obtained.

In other words, when measuring using the method described above using the manufacturing device of this invention, there is almost no change in the measured value even after 300 hours, whereas with the conventional device, the measured value decreases after about 20 hours. However, after 300 hours, the temperature reached about 1160°C.

The reason why good results can be obtained by using the manufacturing apparatus of this invention is that when the susceptor 10 and the semiconductor wafer 7 are heated by the high-frequency heating coil 5 near the longitudinal center of the furnace tube 1, the susceptor 10 and the semiconductor wafer 7 are As the gas temperature rises, the temperature of the tube wall of the furnace tube 1 also rises to several hundreds of degrees Celsius, making it easy for thermally decomposed or reduced silicon to adhere, whereas the lid body 6 is heated by high-frequency heating. This is because it is further away than the coil 5 and located above the gas inlet 3, so that the temperature rise is extremely small, and therefore there is no adhesion of silicon.

In the above embodiment, a case has been described in which the lid 6 is made of stainless steel and the transparent glass windows 6 a and 6 b are hermetically sealed in a part thereof, but the entire lid 6 may be made of transparent quartz.

Moreover, the number of protrusions for temperature measurement provided on the susceptor may be other than two.

As described above, this invention provides a protrusion for temperature measurement on the side surface of the susceptor, and at least a part of the lid is made of a transparent material. This has the effect that layers can be formed with high precision.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view of a conventional semiconductor manufacturing device, Fig. 2 is a longitudinal cross-sectional view of a semiconductor manufacturing device according to an embodiment of the present invention, Fig. 3 is a cross-sectional view thereof, and Fig. 4 is a front view of a lid body. 5A and 5B show temperature characteristic diagrams when temperatures are measured by a conventional method using a conventional device and a method using the device of this invention. 1...Furnace tube, 3...Gas inlet, 5
...Heating means (high frequency heating coil), 6...
...Lid body, 6a, 6b...Transparent glass window, 7
... Semiconductor wafer, 8 ... Wafer support means, 10 ... Susceptor, 10 a, 1
0 b...Protrusion, lla, llb...
- Optical pyrometer.

Claims (1)

[Scope of utility model registration request] A reactor core tube having a wafer inlet/outlet and a gas inlet at one end and a gas outlet at the other end, a lid body for closing the wafer inlet/outlet of the reactor core tube, a heating means surrounding the reactor core tube, and an interior of the reactor core tube. A semiconductor manufacturing apparatus comprising a susceptor placed on a susceptor for mounting a semiconductor wafer, wherein a protrusion for temperature measurement is provided on a side surface of the susceptor, and at least a portion of the lid is formed of a transparent member. Features of semiconductor manufacturing equipment.