JPH01253232A - Method of carrying wafer boat into and out of vertical type furnace - Google Patents

Abstract

PURPOSE:To improve a through-put by a method wherein both ends of a wafer boat are grasped by an almost a horizontal U-shaped clamp, the wafer boat is quickly carried into or carried out to and from a vertical type furnace by rotating the clamp in vertical and horizontal directions. CONSTITUTION:Both ends of a wafer boat 5 are grasped by a clamp 61, and the clamp 61 is raised to the prescribed position using a clamp elevating mechanism 64. ln this state, the clamp 61 is rotated at an angle of 180 deg. in the vertical direction using the first clamp rotating mechanism 62. The wafer boat 5 held by the clamp 61 is brought into the vertical state from the horizontal state. After the clamp 61 has been rotated by 180 deg. in the horizontal direction, the clamp 61 is shifted to the side of the entrance of a furnace, The wafer boat 5 held by the clamp 61 is carried into the main body of the furnace, and it is inserted vertically into a quartz reaction tube. As a result, the carrying-in and carrying out of the boat 5 can be performed quickly, and a through-put can also be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for loading and unloading a wafer boat into a vertical furnace.

[Conventional technology] In recent years, with the increase in the diameter of semiconductor wafers, vertical furnaces have become popular.
It is used for wafer diffusion, CVD, etc. Vertical furnaces usually have a structure in which a heater is placed around a quartz reaction tube with an opening with loading and unloading sections at the bottom. In this method, wafers are arranged vertically at regular intervals on a wafer boat made of quartz or the like so that their surfaces face each other, and the wafer boat is vertically inserted into a reaction tube to perform heat treatment.

By the way, various methods have been proposed for transporting a wafer boat into a vertical furnace or transporting a wafer boat from a vertical furnace. Place it vertically,
A method of horizontally rotating the boat handler in this upright position, moving it to the lower opening of the reaction chamber, and then transporting the wafer boat into the furnace (Japanese Patent Laid-Open No. 61-29133)
Publication No. 5).

[Problems to be Solved by the Invention] However, since the above method lacks stability, there is a problem in that the wafer boat cannot be moved at high speed. Furthermore, when transferring the wafers after heat treatment from the boat to the carrier, the wafers are lifted by a comb-shaped transfer device and taken out from the boat, so there is a possibility that the membrane may be damaged when the wafers are taken out from the boat.

The present invention was made in view of these problems, and
A vertical furnace that allows for rapid loading and unloading of wafer boats into and out of the vertical furnace, and that does not damage the film formed on the wafer surface when transferring wafers after heat treatment from the boat to the carrier. An object of the present invention is to provide a method for loading and unloading a wafer boat.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention grips both ends of a wafer boat with grips having a substantially U-shape, and rotates the grips in vertical and horizontal directions. The feature is that a wafer boat is carried in and out of a vertical furnace.

[Function] By employing the method described above, the present invention can move the wafer boat at high speed and also rotate the wafer boat from a vertically standing state to a horizontally standing state.

〔Example] Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a vertical furnace body (hereinafter abbreviated as the furnace body) with a rectangular envelope shape, and a furnace mouth 2 is provided at the lower front of the furnace body 1.

A wafer transfer table 3 is provided at the bottom of the reactor opening 2, and a carrier 4 for storing a plurality of wafers from the previous process and a wafer boat 5 to be inserted into the reactor are mounted on the wafer transfer table 3. Each is placed at a predetermined position.

The carrier 4 is made of synthetic resin, and 25 wafers W are mounted vertically on the inner surfaces of its opposing side walls at predetermined intervals, for example, at regular intervals, as shown in FIGS. 2(a) and 2(b). A groove 21 for holding is provided. In addition, an opening 22 is provided at the bottom of the carrier 4, and the 25 which is stored in the carrier 4 is passed through this opening 22.
Two wafers W are scooped up at the same time by a wafer transfer machine 6, which will be described later, and pushed upward. In this way, the carriers 4 are arranged in the front row, for example, four in a row. A wafer boat 5 is arranged parallel to this arrangement.

On the other hand, the wafer boat 5 is made of a heat-resistant material such as quartz or SiC, and as shown in FIGS. , holding grooves (not shown) for vertically holding the wafer W are provided in each of these pillars 33 at regular intervals. Gripping projections 34.35 are provided on the outer surfaces of the side plates 31.32, respectively, and these gripping projections 34.3
5 is gripped by a wafer boat transfer device 7, which will be described later.

The wafer transfer machine 6 includes a wafer push-up mechanism 41 that pushes up the wafer W inside the carrier 4, as shown in FIG.
The wafer W pushed up by this wafer push-up mechanism 41
a pair of wafer chucks 42, 43 that sandwich the wafer chucks 42, 43, a wafer chuck opening/closing mechanism 44 that opens and closes the pair of wafer chucks 42, 43, and a wafer chuck that rotates the wafer chucks 42, 43 in the horizontal direction and raises and lowers them in the vertical direction. It is comprised of a rotation and lifting mechanism 45, and a moving table 46 that moves the wafer chucks 42, 43 and wafer push-up mechanism 41 in the arrangement direction of the carriers 4.

As shown in FIG. 5, the moving table 46 is slidably provided on a pair of guide rails 47 and 48 that are arranged parallel to each other, and is moved between the guide rails by rotation of a ball screw 50 connected to a pulse motor 49. 47
, 48. The pulse motor 49 is connected to the control circuit 5 via a motor drive circuit 51.
It is designed to be driven by a signal from 2.

The wafer boat transfer device 7 includes a U-shaped grip 61 that grips both ends of the wafer boat 5, as shown in FIG.
A first grip rotation mechanism 62 that rotates the grip 61 in the vertical direction, a second grip rotation mechanism 63 that rotates the grip 61 in the horizontal direction, and a second grip rotation mechanism 63 that raises and lowers the grip 61 in the vertical direction. The gripping tool elevating mechanism 64 and the gripping tool 61
and a gripper moving mechanism 65 that moves the gripper in the front and back direction.

The first grip rotation mechanism 62 is composed of a motor 66 and bevel gears 67 and 68 that transmit the rotational force of the motor 66 to six rotating shafts projecting horizontally from the back surface of the grip 61. The second grip rotation mechanism 63 includes a motor 70 and bevel gears 71 and 72 that transmit the rotational force of the motor 70 to a rotating shaft 73 vertically installed on the lower surface of the first grip rotation mechanism 62.
It is composed of. Then, the gripping tool elevating mechanism 6
Reference numeral 4 includes a ball screw 74 that vertically raises and lowers the second grip rotation mechanism 63, and a rotational force transmission belt 75 that transmits the rotational force of a motor 76 to the ball screw 74. is a ball screw 77 that moves the gripper lifting mechanism 64 in the front and back direction;
and bevel gears 78 and 79 that transmit the rotational force of the motor 80 to the ball screw 77.

7 to 14 are diagrams showing the operations of the wafer transfer machine 6 and the wafer transfer device 7. Hereinafter, with reference to these diagrams, a method of loading and unloading a wafer boat into a vertical furnace according to the present invention will be explained. explain.

When transferring the wafer W from the carrier 4 to the wafer boat 5, first transfer the wafer W in the carrier 4 as shown in FIG.
is pushed upward by the wafer push-up mechanism 41, and the pushed-up wafer W is placed between a pair of wafer chucks 4 as shown in FIG.
2. Clamp with 43.

Next, the wafer chucks 42 and 43 holding the wafer W are moved to the wafer chuck rotating and elevating mechanism 45 as shown in FIG.
Rotate it 180 degrees horizontally. In this state, the wafer chucks 42-43 are lowered to a predetermined position by the wafer chuck rotating and lifting mechanism 45, and then the wafer chucks 42-43 are opened by the wafer chuck opening/closing mechanism 44 as shown in FIG. As a result, the wafers W held by the wafer chucks 42 and 43 are transferred from the carrier 4 to the wafer boat 5, and are vertically arranged on the wafer boat 5 facing each other at regular intervals.

Next, when carrying the wafer boat 5 into the furnace main body 1,
First, grip both ends of the wafer boat 5 with the gripping tools 61, and
As shown in FIG. 1, the gripping tool 61 is raised to a predetermined position by the gripping tool elevating mechanism 64. Then, in this state, the gripping tool 61 is rotated by 180 degrees in the vertical direction by the first gripping tool rotation mechanism 62 as shown in FIG. As a result, the wafer boat 5 gripped by the gripper 61 changes from a horizontal state to a vertical state. Thereafter, the grip 61 is rotated horizontally by 180 degrees by the second grip rotation mechanism 63 as shown in FIG. Move it to the 2nd side.

As a result, the wafer boat 5 gripped by the gripper 61 is carried into the furnace main body 1, and vertically inserted into the quartz reaction tube by a lifting mechanism (not shown). Note that when the wafer boat 5 is to be taken out of the furnace, the above procedure is reversed.

In this way, both ends of the wafer boat 5 are held by the substantially U-shaped gripping tools 61, and the gripping tools 61 are rotated in the vertical and horizontal directions to carry the wafer boat 5 into and out of the vertical furnace. Since the wafer boat 5 can be moved at high speed, the wafer boat can be quickly carried out and carried out. Furthermore, since the wafer boat 5 can be rotated vertically and the wafers can be transferred with the wafer boat 5 placed horizontally, the film formed on the surface of the wafer can be removed by the wafer transfer machine. It won't cause any damage.

[Effects of the Invention] As explained above, according to the present invention, both ends of the wafer boat are gripped by gripping tools having a substantially U-shape, and the gripping tools are rotated vertically and horizontally to load the wafer boat into a vertical furnace. Since the wafer boat is carried in and out, the wafer boat can be carried in and out of the vertical furnace quickly, and the throughput can be improved.

[Brief explanation of the drawing]

Figures 1 to 14 are diagrams for explaining the method of loading and unloading a wafer boat into a vertical furnace according to the present invention. Figure 1 is a perspective view of the vertical furnace, and Figure 2 (a) is a diagram of the carrier. A plan view, FIG. 3(b) is a front view of the wafer boat, FIG. 3(a) is a front view of the wafer boat, FIG. 4(b) is a side view of the wafer boat, and FIGS. 4 and 5 are the configuration of the wafer transfer machine. FIG. 6 is a diagram showing the configuration of the boat transfer device, and FIGS. 7 to 14 are diagrams showing the operation of the wafer transfer machine and the boat transfer device. DESCRIPTION OF SYMBOLS 1...Furnace main body, 4...Carrier, 5...Wafer boat, 6...Wafer transfer machine, 7...Boat transfer device, 41...Wafer push-up mechanism, 42.43...・Wafer chuck, 44...Wafer chuck opening/closing mechanism, 45
... Wafer chuck rotation and lifting mechanism, 46... Moving table, 61... Gripping tool, 62... First gripping tool rotation mechanism, 63... Second gripping tool rotation mechanism, 64.
...Gripper lifting mechanism, 65...Gripper moving mechanism, W.
...Wafer. Applicant's agent Patent attorney Takehiko Suzue (a) Figure 2 Figure 1 Figure 4 Figure 12 Figure 13

Claims (1)

[Claims] A vertical furnace characterized in that both ends of the wafer boat are gripped by gripping tools having a substantially U-shape, and the gripping tools are rotated vertically and horizontally to carry the wafer boat into and out of the vertical furnace. How to load and unload a wafer boat.