JPH04177830A - Horizontal low pressure vapor growth device - Google Patents

Abstract

PURPOSE:To prevent the oxidation of a contact hole in the case of making a polycrystalline silicon film for electrode wiring formation so as to reduce contact resistance by providing a means for putting the inside of a carry part in inert gas atmosphere. CONSTITUTION:The carry part 11A at the front of a reactor 1 is composed of a cover 12, which is provided with a hatch 12 for carrying in and carrying out the boat 5 carrying a wafer, nitride pipes 3, which have nozzles 3A-3H for introducing nitride gas into this, and lower exhaust pipes 4A-4F. Accordingly, it becomes possible to lower the concentration of oxygen in the vicinity of the silicon wafer carried in the furnace. Hereby, in the case of using a polycrystalline silicon film for electrode wiring, the oxidation of the contact hole is prevented, and the contact resistance is reduced.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a horizontal reduced pressure vapor phase growth apparatus.

[Conventional technology]

The conventional horizontal reduced pressure vapor phase growth apparatus, as shown in Fig. 3,
The reactor 1 has a structure in which a pack hatch nitrogen pipe 6 and a vacuum exhaust pipe 7 are provided at one end, and a conveying section 11 having a hatch 12 and an exhaust pipe 8 is provided at the other end. A boat carrying semiconductor substrates (hereinafter referred to as wafers) is transported into the reactor 1 from this transport section 11.

[Problem to be solved by the invention]

The transfer section 11 in front of the reactor in the conventional horizontal reduced pressure vapor phase growth apparatus described above has a structure in which only the exhaust pipe 8 is provided, so when the hatch 12 is opened and the wafer is carried in,
The atmosphere at the mouth of the reactor 1 has a high oxygen concentration.

Therefore, oxygen remains between the wafers. In this state, when the wafer is carried into a furnace at 600 to 650°C and a polycrystalline silicon film for forming electrode wiring is formed over the contact hole formed in the wafer, the contact hole portion is oxidized, and this oxide film Therefore, there was a drawback that the contact resistance of the electrode wiring became high.

[Means to solve the problem]

The horizontal reduced pressure vapor phase growth apparatus of the present invention is a horizontal reduced pressure vapor phase growth apparatus in which a semiconductor substrate is transferred from a transfer section provided at one end of a reactor, and a method for creating an inert gas atmosphere in the transfer section. This means that a means has been established.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a cross-sectional view of a first embodiment of the invention.

In FIG. 1, a conveyance section 11A on the front side of the reactor 1 includes a hatch 1 for taking in and taking out a boat 5 carrying wafers.
2, a nitrogen pipe 3 having nozzles 3A to 3H for introducing nitrogen gas into the cover 12, and four lower exhaust pipes 4A to 4F. Note that 2 is a heater, 6 is a pack hatch nitrogen pipe, and 7 is a vacuum exhaust pipe.

Next, in order to confirm the effect of this example, an n" diffusion layer was partially formed on a silicon semiconductor substrate, a phosphosilicate glass film was deposited, and only the n+ diffusion layer region was formed by photolithography. A contact hole is formed, and in this state, a polycrystalline silicon film with a thickness of 500 to
After 1000 layers were grown, aluminum was deposited by sputtering, an aluminum electrode wiring pattern was formed by photolithography, and the contact resistance was measured.

The contact size on the mask is 0.8μm2゜1.0μ
The number of contacts is 500 in three types of m2 and 1.4 μm2. Also, the growth conditions for the polycrystalline silicon film are a growth temperature of 6
00~650°C Monosilane flow rate 1.0~2. Off/
min, product input speed is 100-200cm/
m1n - 50~ to reduce the oxygen concentration in the furnace when entering the furnace
] 00 e/min nitrogen was flowed from the back batch nitrogen pipe 6. Further, the nitrogen flow rate of the conveying section 11A in this embodiment is 6 kg in pressure.

The test was carried out under conditions of 0 m2 and 30 ff/min per nozzle.

As a result, as shown in FIG. 4, the contact resistance of this embodiment could be made extremely low compared to the conventional device.

FIG. 2 is a cross-sectional view of a second embodiment of the present invention.

In the first embodiment described above, the oxygen concentration is lowered by replacing the conveying section with nitrogen, but in this second embodiment,
In this embodiment, the cover 12 is provided with a sealing hatch 12A and a front hatch 9 to make it airtight, and before the boat 5 enters the furnace, the transfer section 11A is evacuated with the rotary pump 10, and then the nitrogen pipe 3 is removed. The system uses nitrogen to reach atmospheric pressure. The second embodiment also provides the same effects as the first embodiment.

〔Effect of the invention〕

As explained above, the present invention makes it possible to lower the oxygen concentration near the silicon wafers carried into the reactor by providing a means for creating an inert gas atmosphere in the transport section before the reactor. When a polycrystalline silicon film is used for electrode wiring, oxidation of the contact hole portion can be prevented and contact resistance can be reduced.

[Brief explanation of the drawing]

1 and 2 are sectional views of the first and second embodiments of the present invention, FIG. 3 is a sectional view of the conventional example, and FIG. 4 is the area and contact resistance of the contact hole according to the embodiment and the conventional example. FIG. 1... Reaction furnace, 2... Heater, 3... Nitrogen piping,
3A to 3D... Nozzle, 4A to 4F... Lower exhaust pipe, 5... Boat, 6... Pack hatch nitrogen piping, 7.
・Vacuum exhaust pipe, 8,8A...Exhaust pipe, 9...Front hatch, 10...Rotary pump, 11. IIA
...Conveyance section, 12...Hatch, 12A...Sealing hatch 9 Agent Patent attorney Uchihara Sound Publication number N ＼ 0.8 1.0 1.4 Contact F
Hole surface R (Am2) Fig. 4

Claims (1)

[Claims] A horizontal reduced pressure vapor phase growth apparatus for transporting a semiconductor substrate from a transport section provided at one end of a reactor, characterized in that a means for creating an inert gas atmosphere in the transport section is provided. Vapor phase growth equipment.