JPH06196408A - Vertical lpcvd device and thin film glowth method - Google Patents

Abstract

PURPOSE:To cut down the time for purging and loading of the wafers of the next lot by a method wherein the second hatch different from the first hatch fitted to a wafer loading boat is provided to vaccumize a growth chamber for sealing by the second hatch. CONSTITUTION:As soon as the growing step is finished; a hatch 5 is lowered to discharge a boat 3 and wafers out of a growth chamber, the growth chamber is kept airtight by the second hatch 6 to evacuate the growth chamber for starting the purging step. During such steps, the wafers are cooled down and collected from the boat 3 and then the wafers of the next lot are loaded onto the boat 3. Through these procedures, such steps as the evacuation of the growth chamber after the wafers re taken out of the growth chamber, purging and the collection of wafers out of the boat and the loading of the wafers of the next lot onto the boat 3 can be performed simultaneously.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a vertical LPCVD apparatus which is widely used for forming wirings and insulating films in a semiconductor manufacturing process.

[0002]

2. Description of the Related Art The structure of a conventional vertical LPCVD apparatus is shown in FIG.
Shown in.

The growth chamber is composed of an outer tube 1, an inner tube 2 and a hatch 5. Airtightness is maintained by the outer tube 1 and the hatch 5, and a vacuum pump (not shown) exhausts air from the exhaust port 4 to create a vacuum state. Further, a boat 3 for loading wafers is arranged on the hatch 5 and moves slowly vertically in the downward direction when loading and unloading the wafer and upwards in other times.

[0004]

In the vertical LPCVD apparatus, in order to remove the residual gas after the film forming process, evacuation of the growth chamber and N ₂ purge are repeated. This evacuation, N
₂ Sufficient purging will prevent the generation of particles. Therefore, after the wafer is in the growth chamber, vacuuming and purging are performed, and then the wafer is taken out of the growth chamber and then vacuuming and purging are performed again.

However, in the conventional vertical LPCVD apparatus, since the boat on which the wafer is mounted is arranged on the hatch for maintaining the vacuum, the wafer is taken out of the growth chamber and then the growth chamber is evacuated again. This requires a lot of time in the steps of descending the boat, cooling the wafer, recovering the wafer, raising the hatch, vacuuming the growth chamber, purging, lowering the hatch, and loading the next lot of wafers.

[0006]

A vertical LPCV according to the present invention
The device D has a second hatch separately from the hatch in which the wafer loading boat is installed, and the growth chamber can also be vacuum-sealed by this second hatch.

[0007]

As described above, if the second hatch is provided,
After the growth process is completed, when the hatch in which the boat is arranged is completely lowered, the growth chamber can be kept airtight by the second hatch, and vacuuming and N ₂ purging can be performed immediately.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a vertical LPC according to an embodiment of the present invention.
It is sectional drawing of a VD apparatus. In the figure, 1 is an outer tube, 2
Is an inner pipe, 3 is a wafer loading boat, 4 is an exhaust port, 5
Is a hatch for raising and lowering the boat and for vacuum sealing during growth, and 6 is a second hatch.

Next, the operation of the above vertical LPCVD apparatus will be described.

According to this embodiment, when the growth is completed, the hatch 5 descends, and the boat 3 and the wafer come out of the growth chamber, the second hatch 6 immediately keeps the growth chamber airtight, and the vacuum in the growth chamber is maintained. Pull and purge. During this time, the wafers are cooled, the wafers are collected from the boat, and the next lot of wafers is loaded into the boat.

According to this embodiment, there is an advantage that the growth chamber can be evacuated after taking out the wafer from the growth chamber, purge and recovery of the wafer from the boat, and mounting of the next lot of wafers on the boat can be performed at the same time. is there.

[0013]

As described above, according to the present invention, since the second hatch is provided, the evacuation of the growth chamber after the wafer is taken out from the growth chamber, the purging and the recovery and mounting of the wafer are performed simultaneously. Therefore, there is an effect that the time from the completion of the processing of the previous lot to the start of the processing of the next lot can be shortened.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a growth chamber constituting portion of a vertical LPCVD apparatus of the present invention.

FIG. 2 is a vertical cross-sectional view of a growth chamber constituting portion of a conventional vertical LPCVD apparatus.

[Explanation of symbols]

 1 outer pipe 2 inner pipe 3 boat 4 exhaust port 5 hatch 6 second hatch

Claims (2)

[Claims] 1. A vertical LPCVD apparatus having a second hatch for vacuum-sealing a growth chamber in addition to a hatch on which a boat for mounting a wafer is set. 2. A method of growing a thin film, characterized in that after the completion of the thin film growth process, when the hatch on which the boat is installed is completely lowered, the second hatch keeps the growth chamber airtight and vacuum N ₂ purge is performed. .