JPS6333814A - Normal pressure continuous vapor growth apparatus - Google Patents

Abstract

PURPOSE:To reduce the number of steps of cleaning a tray thereby to improve the operability by surrounding the moving path of the tray to be heated with a heat-insulating member to form a heat insulating chamber therein. CONSTITUTION:A heater 4 is disposed as heating means inside the moving path 3 of a tray, the outside is surrounded by a heat-insulating member (heat insulating material) 5 to form a heat insulating chamber 10 therein, thereby keeping a tray temperature constant. A wafer 6 is placed from an inlet 7 formed on the way of the member 5 of the tray 1, a vapor-deposited film (CVD film) is formed with reaction gas diffused from a gas nozzle 8 while passing under the nozzle 8, and conveyed out from an outlet 9 formed on the way of the member 5. Thus, since the tray 1 is held substantially at a constant speed during the operation, the CVD film deposited on the tray 1 is stabilized, the tray 1 is not simply separated, and the number of separating the whole surface can be remarkably omitted.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention relates to an atmospheric continuous vapor phase growth method in which vapor phase growth is performed while continuously moving a plurality of trays on which wafers are placed. This invention relates to improvement of a growth apparatus (normal pressure continuous CVD apparatus).

(Prior Art) A conventional normal pressure continuous vapor phase growth apparatus has a basic configuration as shown in FIG. That is, the structure is such that the trays b connected in a caterpillar manner move continuously as the sprockets rotate.

Here, a heater e for heating the tray b and the wafer d placed on the tray b is installed near the bottom of the gas nozzle C. Tray b has a vapor growth temperature of about 450
The cycle is such that the temperature is heated to 450°C, then the temperature is lowered to about room temperature, and then heated to 450°C again.

(Problems to be Solved by the Invention) However, in such a conventional normal pressure continuous CVD apparatus, the wafer d is placed on the tray b and passed under the gas nozzle 13 from which the reaction gas is emitted to form a film continuously. Because of the structure in which wafers d are not present on tray b, a film of a sl compound is deposited over time, and due to the difference in thermal expansion coefficient between tray b and the sl compound film, The cracks peel off from the redo layer b and become dust, which causes wafer defects.

For this reason, it becomes necessary to completely peel off the 81 compound film from tray b periodically, which is not only quite troublesome but also
There is a problem in that a considerably long time of 4 to 8 hours is required, and the operating efficiency of the apparatus is reduced.

The present invention has been made based on the above-mentioned circumstances, and its purpose is to reduce the number of times the tray is cleaned to prevent defects caused by dust during wafer coating processing, and to reduce the number of times the tray is cleaned in order to prevent defects caused by dust during wafer coating processing. The purpose is to provide an atmospheric pressure continuous vapor phase growth apparatus that makes it possible to increase the temperature.

[Configuration of the Invention (Means for Solving the Problems) In order to solve the above problems, the present invention performs vapor phase growth while continuously moving a plurality of trays for placing wafers. An atmospheric pressure continuous vapor phase growth apparatus, comprising a heating means for heating the tray, and a heat insulating means for surrounding a moving path of the tray heated by the heating means with a heat insulating member to form an insulating chamber inside. It is structured as follows.

(Function) That is, with the above configuration, the present invention can maintain the temperature of the tray constant so that the S1 compound attached to the tray does not peel off, thereby reducing the number of times the tray is cleaned. This makes it possible to improve operability.

(Example) FIG. 1 shows an example of the present invention. In the figure, 1... is a tray connected in a caterpillar style, and these trays...
runs endlessly in the direction of arrow A as the sprockets 2, 2 rotate. In addition, the movement path 3 of tray 1
A heater 4 as a heating means is disposed inside the tray, and the outside is surrounded by a heat insulating material 5 to form an insulating chamber 10 to keep the tray temperature constant. composition. The wafer 6 is placed on the tray 1 from a loading lower installed in the middle of the heat insulating member 5, and while passing under the gas nozzle 8, a CVD film is formed by the reaction gas blown out from the gas nozzle 8, and the wafer 6 is heat insulated. Part 5
It is carried out from an outlet 9 provided in the middle.

According to this apparatus, since the tray 1 is kept at a constant temperature during operation, the CVD film attached to the surface of the tray 1 is stable and does not easily peel off from the tray 1.

When the thickness of the CVD film on the tray 1 reaches its limit, the loading of wafers 6 to the tray 1 is stopped, the heater 4 is turned off after waiting for the processing of the loaded wafers 6 to be completed, and preferably, the loading of the wafers 6 is stopped. Lower, unloading port 9. Cool air is sent from the gas nozzle 8 or between the heater 4 and the heat insulating member 5 to rapidly cool the CVD film attached to the surface of the tray 1 and generate cracks.
It is preferable to facilitate the peeling off of the CVD film and to cool the tray 1 in a short time. Peeling of the CVD film from the tray 1 is carried out outside the machine by taking out the tray 1 from the loading or unloading lower 9 and replacing it with a clean one.

[Effects of the Invention] As explained above, in the present invention, in the conventional device, the 81 compound film has many cracks when the film thickness on the tray is about 10 μm.
Whereas it was necessary to peel off the entire surface, the apparatus of the present invention reduced the total surface peeling to 30μ, making it possible to greatly reduce the number of times the entire surface was peeled off.

[Brief explanation of the drawing]

FIG. 1 is a front view of the atmospheric continuous vapor phase growth apparatus of the present invention, and FIG.
The figure is a front view of a conventional atmospheric pressure continuous vapor phase growth apparatus. DESCRIPTION OF SYMBOLS 1... Tray, 3... Tray movement path, 4... Heater (heating means), 5... Heat insulating member (heat retaining material), 6...
...Wafer, 10...Insulation room.

Claims (2)

[Claims] (1) In an atmospheric continuous vapor phase growth apparatus that performs vapor phase growth while continuously moving a plurality of trays for placing wafers, a heating means for heating the trays and a heating means for heating the trays are provided. 1. An atmospheric continuous vapor phase growth apparatus characterized by comprising a heat insulating means for surrounding a movement path of the tray with a heat insulating member and forming an insulating chamber therein. (2) The atmospheric pressure continuous gas phase according to claim 1, wherein the insulating room is configured to introduce nitrogen gas and expose a part or the entire tray to a nitrogen gas atmosphere. growth equipment.