JPS63136529A - Production device for semiconductor - Google Patents

Abstract

PURPOSE:To automate the setting and resetting of a wafer easily without damaging the uniformity of film thickness by manufacturing a cage covering a boat by a metal while fixing the cage to a reaction pipe and setting the boat into said reaction pipe under the state in which the boat is inserted into a cage- shaped cover when the wafer is mounted thereon. CONSTITUTION:A cage-shaped cover 15 made of SUS is fastened to a reaction pipe 11, on the periphery of which a heater 12 is desposed and which is made of quartz, through an annular flange 13 and four structs 14 respectively, and a plurality of slits 15a... in the same width are shaped in the longitudinal direction. A boat 16 made of quartz in which a plurality of wafers are set in a cross arrangement manner is inserted into the cover 15 in the reaction pipe 11 by an elevator 17 in said cover 15. A boat rolling mechanism 20 is mounted to a flange door 19, and a boat susceptor 21 supporting said boat 16 is rotated. Accordingly, the setting and resetting of the wafers are automated easily while reducing cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a semiconductor manufacturing apparatus, and particularly to a vertical reduced pressure CVD apparatus in which a cage-shaped cover is fixed inside a reaction tube.

(Prior art) Conventionally, when forming a film using low pressure CVD where the film formation reaction is rate-limiting, such as the formation of an SiO2 film using the S I H4-02 system, a cage was used to obtain good film thickness uniformity. A type of boat is used.

Conventionally, as a vertical reduced pressure CVD apparatus using such a boat, the one shown in FIG. 2 is known.

1 in the figure is a quartz reaction tube with an open bottom end.

This reaction tube 1 is placed on a flange door 3 via a flange 2. A boat support 4 is provided inside the reaction tube 1, and the support 4 is rotatable by a boat rotation mechanism 5 attached to the flange 3. A cage-shaped boat 6 shown in FIG. 4 is set on the support stand 4. As shown in FIG. As shown in FIG. 5, this boat 6 is comprised of a quartz boat body 6a that holds wafers, and a quartz cover 6b that can be freely fitted onto the quartz boat body 6a.

Further, the boat 6 is inserted into the reaction tube 1 by an elevator mechanism (not shown).

Incidentally, the automation of the setting of tools for general quartz boats is progressing, and automation is particularly easy for a single vertical low-pressure CVD system. However, the conventional device has the following problems.

■The work of fitting the cover 6b to the boat body 6a is essential and difficult to automate;
The contact area between the cover 6b and the cover 6b also increases. the result,
This leads to an increase in particles during the process and is prone to human error.

■Since the positional relationship between the wafer and the cage-shaped boat 6 is fixed, the thin film formed on the wafer has locally thicker parts 7 depending on the shape of the boat 6, as shown in FIG.
appears. Note that 8 in the figure indicates a wafer.

Also, a vertical low pressure CVD device is known that uses a metal boat instead of a quartz boat, but in such a device, the film that accumulates on the boat due to the difference in thermal expansion coefficient when the boat is taken in and out is Peeling off, resulting in particle contamination.

(Problems to be Solved by the Invention) The present invention has been made in view of the above circumstances, and it facilitates automation of wafer setting and resetting without impairing film thickness uniformity, and reduces boat costs. The purpose of the present invention is to provide a semiconductor manufacturing apparatus that can be used for manufacturing semiconductor devices.

[Structure of the Invention] (Means for Solving the Problems) The present invention consists of a reaction tube made of quartz around which a heating means is arranged, and a reaction tube made of gold A with one end opened and fixed in the reaction tube. It consists of a cage-shaped cover and a boat that is removably inserted into the cage-shaped cover, and the gist is that when loading wafers, the boat is inserted into the cage-shaped cover and set in the reaction tube.

(Function) The present invention is characterized in that the basket covering the boat is made of metal, and this basket is fixed to the reaction tube, so that the entire boat is inserted into the cover when loading wafers. Therefore, in the formation of films such as SiO2 films using the S i H4-02 system, where the film formation reaction is the rate-limiting supply, it is possible to easily automate the setting and resetting of wafers without impairing the uniformity of the film thickness, and to reduce the cost of the basket. can be reduced. In particular, when applied to a vertical low-pressure CVD apparatus, there is also the effect of reducing particles and improving the uniformity of film thickness, and as a result, significant effects such as improved yield and productivity can be expected.

(Example) An embodiment of the present invention will be described below with reference to FIG.

However, FIG. 1 shows a state in which the boat part, cover, and quartz tube part are separated.

11 in the figure is a quartz reaction tube around which a heater 12 is arranged. This reaction tube 11 has an annular flange 13.
．． A cage-shaped cover 15 of 5 usi is fixed via four pillars 14, respectively.

This cover 15 is provided with a plurality of slits 15a having the same width in the vertical direction. Inside the cover 15 is a quartz boat 1 in which a plurality of wafers are set side by side.
6 is the cover 15 inside the reaction tube 11 by the elevator 17.
inserted within. An elevator support 18 is erected on the elevator 17, and a flange door 19 is fixed thereto. This flange door 19 has a boat rotation I (
#! 20 is attached, and this rotation mechanism 20 rotates a boat support stand 21 that supports the boat 16.

According to the above embodiment, the effects listed below are obtained.

- Since the cage-shaped cover 15 and the quartz boat 16 are not in contact with each other, generation of particles can be suppressed.

(2) Since the cage-shaped cover 15 and the boat 16 have independent structures, only the boat 16 can be rotated by the boat rotation mechanism 17 while the process is in progress. Therefore, basket 15
The relative position of the wafer is not fixed, and local variations in film thickness can be suppressed.

(2) Since the cover 15 is fixed in the furnace during the cleaning cycle of the reaction tube 11, the temperature does not drop. Therefore,
There is no need to consider the generation of particles due to film peeling due to differences in thermal expansion coefficients as in the conventional method.

- Since the cover 15 is made of SUS, it is easy to process, and the manufacturing cost can be significantly reduced compared to conventional covers (made of quartz).

In the above embodiment, SUS is used as the material of the cover, but the material is not limited to this, and a material having a small difference in expansion coefficient from quartz, such as Inconel, may also be used.

Further, in the above embodiment, a cover having vertical slits of the same width is used, but the cover is not limited to this. For example, as shown in FIG. 6, there is a basket-shaped cover 22 made of gold II with a slit 21 whose width gradually increases from the bottom to the top, or an opening 23 whose diameter gradually increases from the bottom to the top as shown in FIG. A metal cage-shaped cover 24 having a diameter may be used. If a film is formed using a cover having such a structure, the reaction gas is uniformly supplied to a plurality of wafers, and the film thickness of the wafers can be formed more uniformly.

Further, in the above embodiments, the case where the present invention is applied to a vertical reduced pressure CVD apparatus has been described, but the present invention is not limited to this, but can be similarly applied to a general reduced pressure CVD apparatus in which the furnace body is arranged horizontally.

[Effects of the Invention] As detailed above, according to the present invention, it is possible to easily automate the setting and resetting of wafers without impairing the uniformity of film thickness, and to reduce costs, and it is particularly suitable for vertical low pressure CVD equipment. If applied, it is possible to provide a semiconductor manufacturing 5A device that can reduce particles and improve uniformity of film thickness.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a vertical reduced pressure CVD apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of a conventional vertical reduced pressure CVD apparatus,
Fig. 3 is an explanatory diagram of problems caused by the same device, Fig. 4 is a perspective view of a basket related to the same device, Fig. 5 is a perspective view showing the divided state of this cage, and Figs. 6 and 7 are respectively FIG. 7 is a perspective view showing another embodiment of the cage according to the device of the present invention. DESCRIPTION OF SYMBOLS 11... Quartz reaction tube, 12... Heater (heating means), 13... Flange, 14... Support column, 15.2
2゜24...Cover, 16...Quartz board, 1
7...Elevator, 1...Flanged door, 20...
- Boat rotation mechanism, 21... boat support stand. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 Figure 4 Figure 5 Figure 6 Figure 7

Claims (2)

[Claims] (1) A reaction tube made of quartz with heating means arranged around it, a metal cage-shaped cover with one end open fixed inside the reaction tube, and a cage-shaped cover inserted into the cage-shaped cover so as to be freely removable. 1. A semiconductor manufacturing apparatus comprising: a boat; the boat is inserted into a cage-like cover and set in the reaction tube during wafer loading. (2) The semiconductor manufacturing apparatus according to claim 1, wherein the boat is made of quartz or ceramic.