JPH0362515A - Vacuum heating processor - Google Patents

Abstract

PURPOSE:To increase the capacity of the elements to be processed while enhancing vacuum exhausting efficiency and heating efficiency by a method wherein multiple heating plates arranged at intervals in the vertical direction in a vacuum chamber are lifted and lowered. CONSTITUTION:In order to deliver substrates 30 into a vacuum chamber 1, the inside of the vacuum chamber 1 is made in a state of atmospheric pressure and a gate 3 is opened and then the levels of respective heating plates 7a-7d are equalized with the level of an arm 26 of an unloading means 24. After finishing the delivery of the substrates 30 to the heating plates 7a-7d, the gate 3 is closed; reducing gas is led-in from a gas leading-in port 6 and exhausted from an exhaust port 5 to vacuumize the vacuum chamber 1 in specific vacuum state again with the reducing atmosphere. At this time, the vacuum chamber 1 in relatively less volume in comparison with the capacity of the substrates 30 can be vacuumized in the specific vacuum state within relatively short time so that the vacuum exhaustion efficiency, heating efficiency and processing capacity may be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a vacuum heat treatment apparatus, and in particular to a CvD (CvD)
chemical vapor
The present invention relates to a vacuum heat treatment apparatus that can be suitably applied to a preheating chamber or the like in a vacuum reaction apparatus such as a vacuum reaction apparatus such as a vacuum heat treatment apparatus.

Conventional technology For example, a thin film is formed on the surface of the workpiece by heating and holding the workpiece in an evacuated reaction chamber and supplying a compound gas containing the constituent elements of the thin film to be formed into the reaction chamber. CVD equipment usually has a preliminary chamber called a load-lock chamber that can be evacuated so that objects to be processed can be brought in and taken out while maintaining the reaction chamber in a vacuum state. After the workpiece is transferred between the chamber and the outside, the workpiece is placed in a vacuum state, and after the processing in the reaction chamber is completed, the workpiece is transferred between the reaction chamber and the preliminary chamber. It is configured so that processing can be resumed immediately. Furthermore, there is also known a device in which a heating means is disposed in the load lock chamber to preheat the object to be processed in the load lock chamber, thereby reducing the heating time in the reaction chamber.

For example, as shown in FIG. 3, a load-lock chamber equipped with such a heating means is configured such that a mounting table 32 on which a substrate 30 as an object to be processed is placed is installed in a load-lock chamber 31, and A sheathed heater 33 is built into this mounting table 32, and the substrate 30 is heated by heat transfer on the heated mounting table 32. In FIG. 3, 34 is a reaction chamber 35, 36 is a gate provided between the reaction chamber 34 and the load lock chamber 31, and between the load rotor chamber 31 and the outside, and 37 is a gate provided from the outside to the load lock chamber 31. A means (not shown) for transferring the substrate 30 from the load lock chamber 31 to the reaction chamber 34 is also provided. Also, instead of the sheathed heater 33, there is also a heating device that uses radiation heating means such as a heating lamp.

On the other hand, as shown in FIG. 4, in order to reduce the number of times the load lock chamber 31 is evacuated and returned to atmospheric pressure, a tray 38 on which a plurality of substrates 30 are placed is placed between the load lock chamber 31 and the outside. Loading and unloading is possible, and there is a loading room 3
There is one in which the substrate 30 carried into the device 1 is heated by radiation using a heating means 39 disposed above the substrate 30.

As this radiation heating means, a sheathed heater built-in, a heating lamp, etc. are used.

Problem to be Solved by the Invention However, with the configuration shown in FIG. There is a problem of inefficiency due to the need to perform recovery. Furthermore, if an attempt is made to increase the number of substrates 30 that can be accommodated in the load rotor chamber 31, the area of the i-Dlock chamber 31 will increase, requiring a large space, and the volume will increase approximately in proportion to the number of substrates. The problem is that it takes a lot of time and cannot be a solution to the essential problem. Further, when a radiation heating method is adopted, there is a problem that thermal efficiency is also poor.

Further, even in the configuration shown in FIG. 4, the area of the load rotor chamber 31 becomes large, resulting in the same problem, and a conveying means for the tray 38 is required as a means for transferring the substrate 30, but this is a conveying means that can be applied to a vacuum heating chamber. Since it is necessary to take into account the thermal deformation of the tray 38 during heating, the configuration becomes very complicated.
There was a problem in that the reliability of transportation decreased. Furthermore, since a radiation type heating means has to be adopted, there is a problem of poor thermal efficiency.

In view of the above-mentioned conventional problems, an object of the present invention is to provide a vacuum heat treatment apparatus that can increase the number of objects to be treated without significantly increasing the installation space and volume, and has good vacuum evacuation efficiency and thermal efficiency. shall be.

Means for Solving the Problems In order to achieve the above objects, the present invention provides a vacuum chamber that can be evacuated to a predetermined vacuum state, and a plurality of heating stages arranged vertically spaced apart from each other within this vacuum chamber. The heating plate is characterized by comprising: plates and means for driving the heating plates up and down.

Preferably, each heating plate has a built-in sheathed heater as a heating means, and a conduit that is connected to the outer tube in a vacuum-sealed state and led out to the outside of the vacuum chamber, and a heater inserted into the conduit. It is equipped with a supply line.

Function According to the present invention, since the heating plates on which the objects to be processed are placed in the vacuum chamber are arranged in multiple stages in the vertical direction, the number of objects to be processed can be increased, and the installation space is not increased. Since the volume of the vacuum chamber does not need to increase much, the vacuum evacuation efficiency is high, and since these heating plates are moved up and down, a simple means for transferring the workpiece can be used, and the Heating efficiency is also good because objects are heated using a heat transfer method using a heating plate.

In addition, the outer tube of the sheathed heater serving as a heating means is connected to a conduit led out to the outside of the vacuum chamber, and power is supplied through this conduit, so that the interior of the sheathed heater is communicated with the atmosphere even in the vacuum chamber. Therefore, accurate heating control is possible by using a sheathed heater as a heating means without causing discharge.

EXAMPLE Hereinafter, an example in which the present invention is applied to a load lock chamber of a CVD apparatus will be described with reference to FIGS. 1 and 2.

1 is a vacuum chamber serving as a load lock chamber for loading and unloading substrates into and out of the reaction chamber 2;
Openings for passing the substrate 30 are formed on both side walls between the opening for passing the substrate 30 and the reaction chamber, and each is provided with a sealable gate 3.4 so as to maintain a vacuum state. This vacuum chamber 1 has an exhaust port 5, H! connected to an evacuation means (not shown). A gas inlet 6 for introducing a reducing gas such as the like is provided.

Inside the vacuum chamber 1, a plurality of heating plates 7a to 7d are arranged vertically at intervals from each other. Reference numeral 8 denotes a connecting member that connects and holds the heating plates 7a to 7d together. A support shaft 9 that supports these heating plates 7a to 7d is suspended downward from the lowest heating plate 7a, passes through a through hole 10 formed in the bottom of the vacuum chamber 1, and is connected to the lower movable plate 1.
It is fixed at 1. This lower support plate 11 supports the motor 1
It is configured such that it can be driven up and down by an up/down drive means 15 which is controlled by an up/down body 14 screwed onto a feed screw shaft 13 which is rotationally driven by a feed screw shaft 13. The lower movable plate 11 and the peripheral edge of the through hole 10 in the bottom wall of the vacuum chamber 1 are connected by a bellows tube 16, and the vacuum chamber 1
A vacuum state is maintained.

Each heating plate) 7a to 7d has a built-in sheathed heater 17, and as shown in FIG. is connected. The conduit 19 extends upward through a through hole 20 formed in the earthen wall of the vacuum chamber 1, is fixed to an upper movable plate 21, and is opened to the outside atmosphere through the upper movable plate 21. . The lead wire 22 inserted through this conduit 19 connects to the sheathed heater 17.
is connected to the heating wire inside the outer tube. The upper movable plate 21 and the periphery of the through hole 20 in the upper wall of the vacuum chamber 1 are the bellows pipe 23.
The vacuum state of the vacuum chamber 1 is maintained.

Reference numeral 24 denotes a transfer means for receiving and transferring the substrate 30 between the outside and the vacuum chamber 1, and is composed of an arm 26 that can be reciprocated by a feed mechanism 25 or the like.

Next, the effect will be explained.

When transferring the substrate 30 between the vacuum chamber l and the outside,
With the gate 4 closed, the inside of the vacuum chamber 1 is returned to atmospheric pressure, the gate 3 is opened, and each heating plate is heated by the elevating drive means 15).
Adjusting the height position of a to 7d, the arm 2 of the transfer means 24
6, and transfer each heating plate using the transfer means 24)? The substrate 30 is transferred between the terminals a to 7d (heating play)? Since a to 7d are stacked vertically in multiple stages, a large number of substrates 30 can be accommodated in a relatively small vacuum chamber l.

In addition, the height positions of heating plates 7a to 7d are transferred to the transfer means 2.
4, the transfer means 24 can be of a simple configuration.

heating play)? When the transfer of the substrate 30 to a to 7d is completed, the gate 3 is closed, and reducing gas is introduced from the gas inlet 6 and exhausted from the exhaust port 5 to maintain the vacuum chamber 1 in a predetermined reducing atmosphere. Create a vacuum. At this time, since the volume of the vacuum chamber 1 is not large compared to the number of accommodated substrates 30, a predetermined vacuum state can be achieved in a relatively short time, and the evacuation efficiency is high. In addition, lead wires 22 are connected to the sheathed heaters 17 of the heating plates 7a to 7d.
The substrate 30 on each of the heating plates 1-7a to 7d is preheated by applying electricity through the heating plates 1-7a to 7d. At that time, the substrate 30 is heated)
Since heating is performed using a heat transfer method on 7a to 7d, efficient heating can be achieved. Moreover, since the sheathed heater 17 can be used to heat with good controllability, and the inside of the sheathed heater 17 is communicated with the atmosphere, no discharge occurs between the heating wire and the outer tube.

Thereafter, when the thin film forming process in the reaction chamber 2 is completed, the gate 4 is opened and the processed substrate 3o in the reaction chamber 2 is taken out by a transfer means (not shown), and the heated substrate 7a~
The substrate on 7d is inserted into the reaction chamber 2. At this time, the height positions of the corresponding heating plates 7a to 7d are adjusted by the lifting/lowering drive means 15 in accordance with the transfer means. In this way, when the loading and unloading of the substrate 30 between the reaction chamber 2 and the vacuum chamber 1 is completed, the thin film forming process can be immediately restarted in the reaction chamber 2 by closing the gate 4. Furthermore, when all the substrates 30 in the vacuum chamber 1 have been processed by repeating the above operations, the substrates 30 are transferred at one time between the vacuum chamber 1 and the outside as described above.

Effects of the Invention According to the present invention, since the heating plates for placing the objects to be processed are arranged in multiple stages in the vertical direction in the vacuum chamber, the number of objects to be processed can be increased and the installation space is not increased. In addition, since the increase in volume is small, the evacuation efficiency is high, and since these heating plates are moved up and down, a simple structure can be used for transferring the workpiece, and the workpiece can be transferred easily. Heating efficiency is also good because it is heated using a heat transfer method using a heating plate.

In addition, the outer tube of the sheathed heater is connected to a conduit led out of the vacuum chamber, and power is supplied through this conduit, so even in the vacuum chamber, the inside of the sheathed heater is communicated with the atmosphere, so electrical discharge can occur. First, by using a sheathed heater as a heating means, it is possible to control heating with high precision.
It has a great effect.

[Brief explanation of drawings]

1 and 2 show an embodiment in which the present invention is applied to a load lock chamber of a CVD device, and FIG. 1 is a longitudinal sectional view, and FIG.
The figure is a perspective view of a main part, and FIGS. 3 and 4 are schematic configuration diagrams of a conventional example. 1... Vacuum chamber, 7a-7d... Heating plate, 15... Lifting drive means, 17...
... Sheathed heater, 19 ... Conduit, 22 ...
... Lead wire, 24 ... Transfer means.

Claims (2)

[Claims] (1) Equipped with a vacuum chamber that can be evacuated to a predetermined vacuum state, a plurality of heating plates arranged at intervals in the vertical direction within this vacuum chamber, and means for driving the heating plates up and down. A vacuum heat treatment device featuring: (2) A conduit that is connected in a vacuum sealed state to the outer tube of the sheathed heater built into each heating plate and led out of the vacuum chamber, and a power supply line to the sheathed heater that is inserted into the conduit. The vacuum heat treatment apparatus according to claim 1, further comprising a vacuum heat treatment apparatus.