JPH01305514A - Heat treatment furnace for semiconductor wafer - Google Patents

Abstract

PURPOSE:To prevent fine dust and air from entering a silica tube, by a structure wherein divided shutter plates are provided, and opening and closing of the shutter plates are controlled in accordance with the moving position of a fork. CONSTITUTION:During loading operation, after an upper shutter plate 5 and a lower shutter plate 7 are opened, a fork 12 is moved. When semiconductor wafers loaded on a boat 11 on the fork 12 are completely inserted into a silica tube 3, the shutter plate 5 is closed. In addition, when the head of the fork 12 is completely taken out from the silica tube 3, the shutter plate 7 is closed. During unloading operation, only the shutter plate 7 is opened, and the fork 12 is then inserted into the silica tube 3, and thereafter the wafers 10 are taken out from the silica tube 3. In this connection, when the wafers 10 are taken out to the head section of the silica tube 3, the shutter plate 5 is opened, and the fork 12 is then perfectly taken out from the silica tube 3, thereby completing the unloading operation. As a result, an opening area of the silica tube can be made a required minimum value during the loading and unloading operation, and therefore fine dust and air can be effectively prevented from entering the silica tube.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a semiconductor wafer heat treatment furnace, and particularly to a shutter plate structure of a semiconductor wafer insertion and removal section.

[Conventional technology]

Conventionally, the wafer processing procedure of this type of semiconductor wafer heat treatment furnace is as shown in FIG. The port and semiconductor wafer are placed in the heat treatment furnace, and the fork is pulled out of the heat treatment furnace. Loading into the furnace core tube is completed. Next, the semiconductor wafer is heat treated, and after the heat treatment is completed, the fork is used. The semiconductor wafer and ports were then taken out of the heat treatment furnace.

[Problem to be solved by the invention]

In the conventional semiconductor wafer heat treatment furnace described above, when loading and unloading semiconductor wafers, the shutter plate 15 shown in FIG. 5 cannot be closed due to the fork and the semiconductor wafer, and the open end of the quartz tube becomes open. However, due to the inflow and inflow of indoor air, fine dust and oxygen in the air enter the quartz tube. When fine dust adheres to the surface of a semiconductor wafer, it hinders the progress of diffusion and the growth of an oxide film in that area. Furthermore, since the surface of the semiconductor wafer is oxidized by oxygen in the air, it becomes difficult to control the oxide film thickness. Furthermore, there is a possibility that the surface of the semiconductor wafer may be oxidized even in heat treatment such as nitrogen treatment in which the surface of the semiconductor wafer is not desired to be oxidized.

[Differences between the invention and the prior art]

In contrast to the above-mentioned conventional semiconductor heat treatment furnace, the present invention provides a shutter plate divided to match the cross-sectional shape of the fork, and detects the movement position of the fork with a position sensor. The difference is that the opening and closing of the shutter plate is controlled accordingly.

[Means to solve the problem]

The semiconductor wafer heat treatment furnace of the present invention is provided with a shutter plate divided so as to match the cross-sectional shape of the fork supporting the port at the semiconductor wafer insertion/removal portion of the heat treatment furnace, and furthermore, the moving position of the fork is detected by a position sensor. This has the function of controlling the opening and closing of the shutter plate according to the moving position of the fork.

〔Example〕

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

FIG. 1 is a side view of one embodiment of the present invention, FIG. 2 is a front view with the upper shutter plate 5 and lower shutter plate 7 open, and FIG. 3 is a front view with the upper shutter plate 5 closed and the lower shutter plate 7 is a front view with the upper shutter plate 5 open, and FIG. 4 is a side sectional view with the upper shutter plate 5 closed.

In this embodiment, the semiconductor wafer heat treatment furnace is operated as follows.

During the heat treatment, the loading operation moves the fork 12 after opening the upper shutter plate 5 and the lower shutter plate 7. When the semiconductor wafer 10 loaded on the port 11 on the fork 12 completely enters the quartz tube 3, the upper shutter plate 5 is closed. Semiconductor wafer 10 is quartz tube 3
After being placed inside the quartz tube 3, the fork 12 is removed from the quartz tube 3. When the tip of the fork 12 completely comes out from inside the quartz tube 3, the lower shutter plate 7 is closed. In the unloading operation, only the lower shutter plate 7 is opened and the fork 12 is moved. The fork 12 is put into the quartz tube 3, and as the fork 12 rises, the semiconductor wafer 10 loaded on the port 11 in the quartz tube 3 is placed on the load portion of the fork 12 and pulled out from the quartz tube 3, and the semiconductor wafer 10 is placed in the quartz tube. When the tip of the tube 3 is reached, the upper shutter plate 5 is opened, and the fork 12 is then completely pulled out from the quartz tube 3 to complete unloading.

〔Effect of the invention〕

As explained above, the present invention provides a quartz tube during loading and unhooding by using a shutter plate that is divided to match the shape of the fork that supports the port, and controlling the opening and closing of the shutter plate according to the moving position of the fork. Since the opening area can be minimized, it prevents fine dust and air from entering from the open end of the quartz tube, and prevents fine dust from adhering to the surface of the semiconductor wafer, causing diffusion and oxidation in that area. Prevents film growth from being hindered. In addition, the oxidation of the surface of the semiconductor wafer due to oxygen in the air is suppressed, making it easier to control the oxide film thickness, and furthermore, it is possible to suppress the oxidation of the surface of the semiconductor wafer even when it is not desired to oxidize the surface of the semiconductor wafer, such as during nitrogen treatment. It has the effect of

[Brief explanation of the drawing]

FIG. 1 is a side view of one embodiment of the present invention, FIG. 2 is a front view with the upper shutter plate 5 and lower shutter plate 7 open, and FIG. 3 is a front view with the upper shutter plate 5 closed and the lower shutter plate 7 opened. Front view in open state, Figure 4 shows upper shutter plate 5
FIG. 5 is a side sectional view of the conventional configuration. 1...Gas inlet, 2...Heater,
3...Quartz tube, 4...Upper shutter plate drive device, 5...Upper shutter plate, 6...
...Lower shutter plate drive device, 7...Lower shutter plate, 8...Position sensor, 9...
... Guide rail, 10 ... Semiconductor wafer, 11 ... Port, 12 ... Fork, 13 ... Fork support part, 14 ...・・・
・Fork drive device, 15...Shutter plate,
16...Shutter plate drive device. Agent: Patent Attorney Shinsho Uchihara

Claims (1)

[Claims] A shutter plate that is divided to match the cross-sectional shape of the fork that supports the port is installed in the semiconductor wafer insertion and removal part of the semiconductor wafer heat treatment furnace, and the movement position of the fork is detected by a position sensor. A semiconductor wafer heat treatment furnace characterized by controlling the opening and closing of a shutter plate accordingly.