JP2762576B2 - Vapor phase growth equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] Vapor phase growth (CVD) used for forming epi layers or various coatings
The purpose of the equipment is to provide a structure with good film thickness distribution even if the wafer spacing is narrow, and to improve the throughput of the equipment. (1) A reaction chamber (1) and a plurality of substrates in the reaction chamber. A wafer carrier holder (6) for vertically holding a wafer carrier (2) on which a growth wafer is mounted, a gas introduction pipe (3) for introducing a reaction gas into the reaction chamber, and the wafer carrier in the reaction chamber. An inner pipe surrounding the wafer carrier and a plurality of holes opened inside the inner pipe; the exhaust pipe exhausting the reaction chamber from between the inner pipe and the reaction chamber; An inner tube (8), which is closed at the top and bottom,
It is configured such that the gas introduction pipe is provided outside thereof.

(2) The inner tube has an open top and a closed bottom,
The top and the bottom are closed between the inner end pipe and the inner pipe, and the gas inlet pipe is introduced.

[Industrial applications]

The present invention relates to a vapor phase epitaxy (CVD) apparatus used for forming an epilayer or various films.

The CVD apparatus of the present invention can be used for forming an epi layer, a conductive layer, an insulating layer, etc. on a substrate in a wafer process for manufacturing a semiconductor device.

In recent years, epi-CVD apparatuses (broadly-defined CVD apparatuses including epitaxial growth apparatuses) are required to have high throughput, large-diameter wafer processing, and uniformity of film quality and film thickness distribution.

Therefore, there is a demand for an apparatus which is large in size, has a high density of wafers to be processed in the apparatus, and has good uniformity.

[Conventional technology]

In a conventional epi-CVD system, the wafer is placed on a quartz carrier and rotated to make the film thickness distribution uniform.
In addition, the supply and exhaust of the reaction gas are performed as follows.

FIG. 5 is a schematic sectional view of a conventional epi-CVD apparatus.

In the figure, a quartz wafer carrier 2 holding a number of wafers W in a quartz reaction chamber 1 is placed vertically on a wafer carrier holding table 6, and a reaction gas is introduced into a growth chamber from a gas introduction pipe 3. The reaction chamber is maintained at a predetermined gas pressure by adjusting the gas flow rate and the exhaust speed after being exhausted from the exhaust pipe 4.

The wafer carrier 2 has a structure capable of rotating while maintaining hermetic sealing.

The wafer is heated by a heater 7 from outside the reaction chamber 1.

The wafer carrier 2 is surrounded by an inner tube 5 made of quartz in order to prevent the growth film from adhering to the tube wall of the reaction chamber 1 and to form a flow path for spreading the gas flow to all the wafers.

The gas introduction pipe 3 is introduced inside the inner pipe 5, and the exhaust pipe 4 is led out between the inner pipe 5 and the reaction chamber 1. Therefore, the reactant gas flows as shown by the arrows.

However, in this apparatus, when the distance between the wafers is reduced, a thin film thickness distribution is formed at the center, and it is necessary to maintain a certain distance.

[Problems to be solved by the invention]

Therefore, the number of wafers per growth cannot be increased, and the throughput of the apparatus has been reduced.

SUMMARY OF THE INVENTION An object of the present invention is to provide a structure having a good film thickness distribution even when a wafer interval is narrow, and to improve the throughput of the apparatus.

[Means for solving the problem]

The above problems can be solved by: 1. a reaction chamber (1), a wafer carrier holding table (6) for vertically holding a wafer carrier (2) on which a plurality of wafers to be grown are placed, and a reaction gas. A gas introduction pipe (3) for introducing into the reaction chamber, an inner pipe (5) surrounding the wafer carrier in the reaction chamber, and an exhaust pipe (4) for exhausting the reaction chamber from between the inner pipe and the reaction chamber. And an inner tube (8) surrounding the wafer carrier and having a plurality of holes opened inside the inner tube, wherein the inner and inner tubes are closed at the top and bottom, and the gas introduction tube is provided outside the inner tube. A vapor phase growth apparatus or 2. a reaction chamber (1) and a wafer carrier holding table (6) for vertically holding a wafer carrier (2) on which a plurality of wafers to be grown are placed in the reaction chamber. A gas introduction pipe (3) for introducing a reaction gas into the reaction chamber; and a wafer carrier in the reaction chamber. An exhaust pipe for exhausting the reaction chamber from between the inner pipe and the reaction chamber; and a plurality of holes surrounding the wafer carrier inside the inner pipe. And an inner end tube (8), the inner end tube is open at the top and closed at the bottom, and between the inner end tube and the inner tube, the top and the bottom are closed and the gas inlet tube is introduced. This is achieved by a vapor deposition apparatus.

[Action]

According to the present invention, an inner tube having a large number of holes is provided inside an inner tube, and a reaction gas is blown out of the inner tube to diffuse a gas flow from a plurality of openings of the inner tube into a space between wafers. To improve gas flow between wafers,
Alternatively, the top and bottom of the inner tube and the inner tube are closed, and the reaction gas is blown out between the inner tube and the inner tube so that the pressure in this portion is increased so that the gas is uniformly pushed between the wafers through the holes in the inner tube. It was done.

〔Example〕

FIG. 1 is a schematic sectional view of an epi-CVD apparatus according to a first embodiment of the present invention.

In the figure, a quartz wafer carrier 2 holding a number of wafers W in a quartz reaction chamber 1 is placed vertically on a wafer carrier holding table 6, and a reaction gas is introduced into a growth chamber from a gas introduction pipe 3. The reaction chamber is maintained at a predetermined gas pressure by adjusting the gas flow rate and the exhaust speed after being exhausted from the exhaust pipe 4.

The wafer carrier 2 has a structure capable of rotating while maintaining hermetic sealing.

The wafer is heated by a heater 7 from outside the reaction chamber 1.

The wafer carrier 2 is surrounded by an inner tube 5 made of quartz in order to prevent the growth film from adhering to the tube wall of the reaction chamber 1 and to form a flow path for spreading the gas flow to all the wafers.

The above is the same as the conventional example, but different points are as follows.

A closed inner tube 8 at the top is covered on the wafer carrier 2, and a gas introducing tube 3 is introduced outside the inner tube 8.

The inner end tube 8 is made of quartz, and has a large number of holes or slits in its cylindrical surface.

FIG. 2 is a schematic sectional view of an epi-CVD apparatus according to a second embodiment of the present invention.

In this example, the inner tube 8 having an open top is placed around the wafer carrier 2, the tops of the inner tube 8 and the inner tube 5 are closed, and the gas introduction tube 3 is introduced between the inner tube 8 and the inner tube 5. Have been.

 FIGS. 3 (1) and (2) are structural diagrams of the inner tube.

FIG. 3 (1) is a front view, and FIG. 3 (2) is a sectional view.

Holes 81 having a diameter of 5 mm are formed in the cylindrical surface of the inner end tube 8 at a pitch of 20 mm.

 FIGS. 4 (1) and (2) are structural diagrams of another inner tube.

FIG. 4 (1) is a front view, and FIG. 4 (2) is a sectional view.

A long hole (slit) 82 having a width of 5 mm is formed in the cylindrical surface of the inner end tube 8 in eight directions.

 Next, a growth example using this apparatus will be described.

Growth conditions Wafer: 6 inch φ Si wafer Number of processed wafers: 50 Deposition material: SiO ₂ layer Growth gas: SiH ₄ + N ₂ O Growth gas pressure: 0.5 Torr Growth gas flow rate: SiH ₄ 100 SCCM, N ₂ O 1000 SCCM Substrate temperature: 800 ° C In addition to this growth example, in the case of SiN growth, SiHCl ₃
And NH ₃ , and SiH ₄ as a reaction gas in the case of poly-Si growth.

Numerical examples showing the effects of the embodiment are shown below in comparison with the conventional example.

Film pressure distribution Wafer spacing Example ± 5% 1/2 inch Conventional example ± 5% 1 inch From this result, about twice as many wafers can be processed at one time.

〔The invention's effect〕

As described above, according to the present invention, the vertical epi-CV
In the D apparatus, a structure with a good film thickness distribution was obtained and the throughput of the apparatus could be improved even if the wafer interval was narrow.

In addition, the inner tube is sufficiently heated similarly to the wafer, and since the distance between the inner tube and the wafer is narrow, the heat retention effect is higher than when only the inner tube with a large distance is used, preventing heat from being taken away by gas. Therefore, the heat distribution of the wafer is improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an epi-CVD apparatus according to a first embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of an epi-CVD apparatus according to a second embodiment of the present invention, FIGS. 3 (1) and (2) are structural diagrams of an inner tube, and FIGS. 4 (1) and (2) are FIG. 5 is a schematic sectional view of an epi-CVD apparatus according to a conventional example. In the figure, 1 is a reaction chamber, 2 is a wafer carrier, 3 is a gas introduction pipe, 4 is an exhaust pipe, 5 is an inner pipe, 6 is a wafer carrier holder, 7 is a heater, and 8 is an inner pipe.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akio Yamaguchi 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Inside Fujitsu Limited (56) References JP-A-2-138473 (JP, A) JP-A-63-69794 (JP, A) JP-A-63-8624 (JP, A) JP-A-64-7517 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 21/205 H01L 21 / 31 H01L 21/365 H01L 21/469 H01L 21/86

Claims (2)

(57) [Claims] A reaction chamber; a wafer carrier holding table for vertically holding a wafer carrier on which a plurality of wafers to be grown are placed in the reaction chamber; a gas introducing pipe for introducing a reaction gas into the reaction chamber; An inner pipe surrounding the wafer carrier in the chamber; an exhaust pipe for exhausting the reaction chamber from between the inner pipe and the reaction chamber; and a plurality of holes surrounding the wafer carrier inside the inner pipe. A gas phase growth apparatus, comprising: an inner end tube; a top end and a bottom portion of the inner end tube being closed, and the gas introduction tube disposed outside the inner end tube. 2. A reaction chamber, a wafer carrier holding table for vertically holding a wafer carrier on which a plurality of wafers to be grown are placed in the reaction chamber, a gas introduction pipe for introducing a reaction gas into the reaction chamber, An inner pipe surrounding the wafer carrier in the chamber; an exhaust pipe for exhausting the reaction chamber from between the inner pipe and the reaction chamber; and a plurality of holes surrounding the wafer carrier inside the inner pipe. An inner tube having a top opened and a bottom closed, and a top and a bottom closed between the inner tube and the inner tube, and the gas introduction tube being introduced. Vapor phase growth equipment.