JPH01199445A - Supporting device - Google Patents

Abstract

PURPOSE:To make possible an accurate positioning of a body to be supported and to make possible the automatization of a transferring operation of the body to be supported in a device, which makes a force act in the direction opposite relatively to a plurality of supporting mechanisms and supports the body to be supported, by a method wherein at least one supporting mechanism is provided with an expansion and contraction means. CONSTITUTION:In a device 11, which makes a force act in the direction opposite relatively to a plurality of supporting mechanisms 36 and supports a body 9 to be supported, at least above one mechanism 36 is provided with an expansion and contraction means 45. For example, driving bodies 38a and 38b for driving slidingly supporting mechanisms 36a and 36b for grasping both end parts of the semiconductor wafer boat 9 from both sides are respectively constituted of an air cylinder and the coiled spring 45, which is used as an expansion and contraction means, is mounted to the driving body 38b on one side of the driving bodies. Thereby, even the body to be supported having a dimensional error at the time of manufacture of the body to be supported and so on conducts a self-fine adjustment by the expansion and contraction means and can be always supported at a constant position when the body to be supported is supported by the supporting mechanisms. Therefore, a positioning accuracy is improved and it becomes possible to support accurately the body to be supported.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a support device.

(Conventional Technique vfI) When manufacturing a semiconductor device, various thin films are formed on a semiconductor wafer (hereinafter referred to as a wafer).

This thin film is formed by mounting a large number of wafers on a wafer boat and installing this wafer boat inside a reactor or the like. For example, 100 to 150 wafers are loaded on the wafer boat at predetermined intervals.

These wafers are transferred onto a wafer boat from a wafer cassette used for transportation between semiconductor device manufacturing processes. The shape of the boat is set to be suitable for a film forming apparatus such as a reactor.

For example, after forming a thin film on a wafer in one reactor, the boat is taken out of the reactor. Next, the wafer on which the thin film has been formed is transferred from the boat to the original cassette again. The above-mentioned reactors include horizontal furnaces with a horizontal furnace axis and vertical furnaces with a vertical furnace axis. The above cassettes are transferred to the next process, and these operations are performed by automated equipment. The boat is supported by a support device between the wafer transfer position and the boat transfer position. Move back and forth. The wafer transfer position is a position where wafers are transferred from a cassette to a boat or from a boat to a cassette.

A boat receiving station is provided at one transfer point, such as an elevator for carrying boats into and out of a reactor.

The boat is supported on a support device and moved back and forth.

Due to the following reasons. That is, when transporting a boat, transferring wafers, or transferring a boat.

This is to set the boat's position correctly.

FIG. 7 is an explanatory diagram showing a schematic configuration of a conventional boat support device. In FIG. The reason why it is made of quartz glass is to exhibit sufficient heat resistance. A large number of grooves are formed on both sides of the boat (2) at predetermined intervals along its longitudinal direction. The peripheral edge of the wafer (2) is fitted and accommodated in these grooves.

The boat (2) is placed on a boat support stand (2) that constitutes the boat transport mechanism 0. Both ends of the boat α) are held in a state of being pressed from the outside by a support member 0 constituting a boat support device (2).

The surface support member 0 releases its grip on the boat (2) by retreating from both ends of the boat (2). The boat 1 to the support stand (2) are provided on the boat transport mechanism (2) via a movable plate (0). The boat transport mechanism (2) reciprocates on a rail (2) installed between the wafer transfer position and the transfer position of the boat (a). When the boat transport mechanism (2) moves, the boat (2) is supported by the boat support stand (2), and both ends of the boat (2) are held between the supporting members (0).

Then, boat transportation +! & The positioning of the boat (1) on the structure 0 is carried out by controlling the drive of a cylinder (not shown) that raises and lowers the boat support platform 2, a cylinder (not shown) that reciprocates the support member 0, etc. ing.

(Problems to be Solved by the Invention) However, due to errors during boat manufacturing, not all boats (2) necessarily have the same shape.

That is, there are variations in the shape of each boat supported and transported by the boat support device. For this reason, the boat transport mechanism
Even if each cylinder is driven by a predetermined stroke in order to correctly position the boat (■) on the top, the support member 0, etc. may not come into contact with the boat (■), or the support member 0 may come into strong contact with the boat (1). A situation such as too much occurs. As a result, the boat (υ) may not be positioned correctly,
Alternatively, there were problems such as destroying the boat (2).

If the boat (2) is not positioned correctly, it will be difficult to automatically transfer a plurality of wafers (2) from the cassette to each wafer storage groove of the boat (2). As a result, it becomes difficult to automate the manufacturing process of semiconductor devices. Additionally, there was a problem of decreasing throughput.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a support device that enables accurate positioning of a supported object and automates the operation of transferring the supported object.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides an apparatus for supporting a supported body by applying forces in relatively opposite directions to a plurality of support mechanisms, in which at least one of the support mechanisms is provided with an expansion/contraction means. The present invention provides a support device characterized by the following.

(Operation and Effect) According to this support device, at least one of the plurality of support mechanisms that support the supported object is provided with an expansion and contraction means. Therefore, even when a supported object has a dimensional error during the manufacture of the supported object, when it is supported by the support mechanism, it can be self-finely adjusted by the expansion and contraction means and always supported at a constant position. Therefore, the positioning accuracy is high, and it is possible to accurately support the supported object.

Furthermore, since it is possible to support the supported object with high positioning accuracy, it is possible to prevent destruction of the supported object due to inaccurate support.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory diagram showing a schematic configuration of a boat support device according to an embodiment of the present invention. This example uses a semiconductor wafer (
The boat support mechanism for wafers is shown. 0) in the figure is
The wafer boat is made of a heat-resistant material, such as SIC or quartz glass. A large number of grooves (not shown) are formed at predetermined intervals along the longitudinal direction of both ends of the boat 0). These grooves are located on the wafer (1
0) is fitted and housed. For example, there are 10 wafers (10) in this wafer board h (9).
It is designed to accommodate 0 to 150 sheets.

The boat (9) containing the wafers (10) is supported by a boat support device (dan) having the structure shown below, and the wafer (10) transfer position and the boat (10) support are reciprocated between the transfer position. It is supposed to be done.

This boat support device (11) includes, for example, four mounting tables (12a) (12b) (13a) on which the boat (1) is placed.
(L3b). These mounting tables (12a)
(12b), (13a), and (13b) form a pair. That is, the mounting table (12a) (12b)
Each pair of (13a) and (13b) supports boat 0.

FIG. 2 is an explanatory diagram showing the configuration of a pair of mounting tables (12a) and (12b). This a stand (12a) (12b
) is a movable plate (1) that reciprocates along a rail (not shown).
7). The movable plate (17)l has a support (18
) has been established. The top of the strut (18) is provided with a second fitting (19). The second attachment is on the base (19) via a sliding movable part (20) made of, for example, a linear bearing, and the first attachment is on the base (16).
) are laminated. In the first attachment, a quartz glass plate (14) is provided on the base (16). The top surface of the quartz glass plate (14) is the surface that comes into contact with the bottom surface of the boat (9).6 The quartz glass plate (14) is clamped and fixed to the base (16) by a clamping tool (15). There is.

Inside the slide movable part (20), a first slide movable piece and a second slide movable piece (not shown) are provided. 1st
The first attachment of the sliding movable piece is fixed to the base (16). The second sliding movable piece is attached to the base (
The first sliding movable piece fixed to 19) is configured to freely slide along the direction in which the wafers (10) are arranged.

The first attachment is a hook (22a) on the bottom surface of the base (16).
) is screwed on. In the second attachment, a hook (22b) is screwed onto the upper surface of the base (19). A biasing member 1, such as a tension coil spring (21), is stretched between these hooks (22a) and (22b). By this tension coil spring (2I), the base (16) is always biased toward one end in the wafer (lO) arrangement direction in the first attachment. Here, the biasing member may be composed of a slide cylinder or the like.

The mounting table (12a) (12b) has a boat detection mechanism (
23) is installed horizontally. The boat detection Ia structure (23) is for detecting the presence or absence of a boat.

The boat detection mechanism (23) has two shafts (24a) and (24b) vertically arranged at a predetermined interval.

A ball bearing (25) is interposed between both shafts h (24a) (24b). Due to the action of this ball bearing (25), both shafts (24a)
(24b) is.

It is designed to move up and down freely. Both shafts (24
The top of a), (24b) is connected to the base (26). In other words, both shafts (24a) (24b) move up and down as one. base(
26).

The shafts (24a) and (24b) are fixed, and a switch (27) made of quartz is provided at the top of the base (26). A ring-shaped stopper (28) is attached to one of the shafts (24a) where the ball bearing (25) is attached. Stopper (28
) may be attached to the other shaft (24b).The shaft (24a) may be attached to the lower side of the stop bar (2g).
) is inserted into the spring (29). The lower end of the spring (29) is supported by a spring plate (30). Both shafts (24a) (24b) are connected by springs (29).
is biased upward. At the lower end of the other shaft (24b).

A magnet (31) is provided. Magnet (3
A magnet sensor (33) is provided so as to face the sensor 1). The magnetic sensor (33) is first attached to a mount (32) attached to the base (16). By the magnet sensor (33),
It is designed to detect whether the switch (27) is in either a raised state or a lowered state. Note that the magnet (31) may be attached to one shaft (24a) side.

The boat detector fl (23) configured in this way has a pair of mounting tables (12a) (12b) (13a) (1
3b), or one each for each mounting table (12a), (12b), (13a), and (13b).

Two sets of mounting tables (12a) (12b) (13a) (
Pair 13b) has a similar configuration as described above. The other mounting table (13a) (13b) is an arm (35).
It is connected to the cylinder (34) via. By driving this cylinder (34), the other mounting table (13a)
(13b) The pair is designed to move up and down. The cylinder (34) is attached to the lower surface of the movable plate (17).

These mounting tables (12a) (12b) (13a)
(13b) is arranged substantially linearly along the longitudinal direction of the boat (13b) so that its top abuts the bottom surface of the boat (0).

Note that fixed mounting tables (12a, 12b) and vertically movable mounting tables (13a, 13b) are alternately arranged. The reason is that the a placement stand (12a) (12b) (1
3a) This is to place the boat υ on (13b) as stably as possible.

This boat support device (U,) has support mechanisms (36a) (36b) that grip both ends of the boat υ) from both sides. As shown in FIG. 3, the support mechanisms (36a) and (36b) include support members (37) that abut against both longitudinal end surfaces of the boat 0). Support member (37)
are slidably driven by driving bodies (38a) and (38b). The support member (37) also serves as a guide during movement of the support mechanisms (36a) (36b). The support mechanism (36a) (36b) includes a support member (
A cam follower (39) that moves together with the cam follower (37) is provided. A force A, (40) that drives the cam follower (39) is arranged in the support mechanism (36a) (36b).

The support member (37) has an abutment portion conversion mechanism on its upper portion. The contact part conversion mechanism is 1, for example, a rotary solenoid (
41). The support member (37) has, for example, two quartz contact parts (42a) and (42b).

It is installed with an opening angle of 90°. The reason why the contact parts (42a) and (42b) are made of quartz is to exhibit sufficient heat resistance. Rotary solenoid (41
), the positions of the abutting portions (42a) and (42b) can be rotated and exchanged.

Support member (37) that constitutes one support mechanism (36a)
is provided with two contact parts (42a) and (42b).

The support member (37) of the other support mechanism (36b) has two
(43a) (43a) (43b) (4
3b) are provided (see Fig. 4). In other words,
Any one contact portion (4) of one support mechanism (36a)
2a) (42b) and the other support mechanism (36b) of any one pair of contact portions (43a) (43a) (43b)
(43b) comes into contact with both ends of the boat 0) and grips the boat 0 by three-point support.

Contact portion (42a) (42b) (43a) (43b
), the boat 0 may be supported at four points; however, in reality, both end surfaces of the boat 0 may not be parallel to each other. Boat 0 in such cases)
It is extremely difficult to hold it in the correct position with four-point support. In extreme cases, the boat 0 cannot be correctly positioned and gripped due to the four-point support, and the boat 0 will be gripped by the support members (37) (37) in a wobbly state. As a result, it becomes impossible to smoothly transfer the wafers (10) between the cassette and the boat 0. Therefore, the abutting parts (42a) (42b) supported at one point are in contact with approximately the center of the - end face of the boat 0]), and the abutting parts (42a) (42b) are in contact with two points equidistantly apart from the approximate center of the other end face. 43
a) (43a) (43b) (43b) are brought into contact. As a result, the support mechanism (36a) (36b) ensures that the boat
It is something to be grasped by.

The other support member (37) to which the two sets of abutting portions (43a) and (43b) and the rotary solenoid are attached is attached to a rotating shaft (not shown) provided upright on the movable plate (17). The support member (37) is configured to rotate around this rotation axis. A leaf spring is provided through the rotating shaft.

In this way, one end surface of the boat ■ is connected to one point of contact (42a
) (42b), and the other end surface is pressed by two rotatable contact parts (43a) and (43b). As a result, boats (b) of various shapes can be correctly positioned in a stable state.

The support member (37) is slidably driven by driving bodies (38a) (38b). Drive body (3
8a) (38b) is constituted by, for example, an air cylinder. The driving bodies (38a) (38b) are attached to the lower surface of the movable plate (17), for example, in parallel with the support member (37). Drive body (38a) (38
In b), the support mechanisms (36a) (36b) are slid by guides (44a) (44b).

As shown in FIG. 5, at least one driving body (38a)
(38b), the longitudinal direction of the boat (9) and the expansion/contraction direction are the same, and the support mechanism (36a) (36b
) is attached so as to apply forces in relatively opposite directions. The expansion/contraction means is composed of, for example, a coil spring (45). The coil spring (45) is attached to, for example, a piston rod portion of an air cylinder that constitutes the drive body (38b). The mounting position of the expansion/contraction means is the support member (37) (37)
(7) Adjust the mutual facing distance between the driving bodies (38a) (38b)
) Any place that can be freely adjusted by controlling the movement is fine.

Next, conditions for selecting the coil spring (45) will be explained. The selection conditions for the coil spring (45) provided in the piston rod portion are determined by the force with which the cam follower (39) climbs the cam (40).

First, let f be the spring force of a coil spring (not shown) provided inside the support mechanism (36b) to urge the support member (37) downward. Next, the component force in the slope direction due to the angle θ between this spring force f and the force F of the cylinder that is the driving body (38b) is less than the component force in the slope direction of the tension force T of the coil spring (45). do. In this case, the coil spring (45) can move along the slope without stretching.

Here, the resultant force W acting along the slope is determined. As shown in Figure 6A, the force exerted by the air cylinder is PcosO...
・■, If the friction coefficient is μ, the rolling friction due to the air cylinder is μFsinθ...■, and as shown in Figure 6B, the force due to the spring is fsinθ...■.

The rolling friction caused by the coil spring is μfcos 0
... becomes ■. These forces are as shown in FIG. 6C. Therefore, the force W acting along the slope is W=Fcosθ−μ
Fsin O-fsinθ-p fcos O=F
(c08θ-p sin O)-f(sino ten μco
sθ).

Further, the force acting on the slope of the coil spring (45) is Tcosθ. Further, in order for the coil spring (45) to expand when supporting the boat (9), the tensile force T must be less than the cylinder force F.

Therefore, W<TeasθgateT<F This is the conditional expression.

At this time, if the cylinder diameter is d, the air pressure is P, the spring constant of the coil spring (not shown) provided inside the support mechanism (36b) is 2, and the elongation at this time is χ, then F: 2P, f= 2, □χ (if two springs are used in parallel),', W=:'d”PcosO-2, ZsinO
−μd”PsinO−2μKtZcosθ=(Kingd”P
-2μKt Z) cost) - (2K, Z+/j d
2P) sin θ, and the above coil spring (45)
From the conditional expression, T>-7-d"P-2μ, Z-(2K
z Z+μmj-d2P)tanθT<h21, and the coil spring (4
Since a coil spring (45) is provided to select 5), the abutting portions (42a) that come into contact with both end surfaces of the boat 0)
(43a) (42b) (4: lb) The interval between them can be set to the optimum value corresponding to the shape of the boat (9) (7). That is, the contact portions (42a) (43a) (42b
) (43b) is set short in advance. The coil spring (45) can expand and absorb the stroke of the cylinders of the driving bodies (38a) (38b) that is longer than necessary with respect to the boat (9).

Further, the cam follower (39) is connected to the support member (37) via a cam follower support section. The cam follower (39) moves along the cam (40) and the support member (
When the cam follower (39) is moved diagonally upward and grips the 6 boat ■ that supports the boat ■.

It moves diagonally downward along the angle θ.

In order to ensure contact between the cam follower (39) and the cam (40), the support member (37) is always urged vertically downward by a biasing member (not shown).

Next, a method of supporting the boat 0 using the support part rn (11) configured as described above will be explained.

First, the boat support device (11) is installed at the transfer position of the boat (2). The movement of the boat support device (tan) is performed by a movable plate (17) that moves along a rail (not shown). An elevator (not shown) is provided at the transfer position of the boat 0 for transporting the boat h (9) into and out of, for example, a reactor. For example, an elevator has a pair of loading tables (
12a) Lower and place boat 0 on (12b).

Here, when the boat 0 is handed over, the support mechanism (36a
) (36b) is not activated. Therefore, the mounting table (12
a) (12b) is a tension coil spring (21)
It is in a state where it is biased towards one end side in the arrangement direction due to the free length of. Therefore, when the movable plate (17) is stopped at a predetermined position on the rail, the mounting table (12a) (12b)
The boat mounting surface is uniquely determined by the biasing force of the spring (21). Therefore, the boat 0 can always be received on the boat mounting surface at the same position. When boat 0 is placed on the mounting bases (12a) (12b),
The switch (27) of the boat detection mechanism (23) is a boat ■
It descends when placed. In conjunction with this, a magnet (
31) descends. Next, magnet 1-sensor (3
3) detects the placement of boat ■. This boat (9)
When the placement of the support mechanism (36a) (36b) is detected,
is actuated to operate the driving bodies (38a) (38b).

Then, the contact parts (42a) (43a) corresponding to the mounting tables (12a) (12b) move so as to contact both longitudinal end surfaces of the boat 0, respectively. Then, the contact part (42a
) (43a), the cam follower (39
) is driven by a cam (40) inclined diagonally downward at an angle θ. The pressure at the contact parts (42a) (43a) is as follows:
Because not only the pressing force in the direction of the boat (9) but also the resultant force acts diagonally downward, a component force directed vertically downward is generated.

Here, the frictional force acting between the boat 0 and the mounting bases (12a) (12b) is the product of the force perpendicular to the angle θ acting perpendicularly to the friction surface and the friction coefficient.

Therefore, the component force acts vertically downward, increasing the frictional force.

Positioning support forces act on boat 0 in the manner described above. The boat will then move in that direction. At this time, the boat (9) and the mounting table (12a) (1
2b), a considerable frictional force is generated between the two.

No slippage occurs during this time. Therefore, the sliding movable part (11) slides against the biasing force of the tension coil spring (21), and the boat
) is positioned and supported.

In this way, when positioning and supporting the boat (9), the mounting table (
12a) No slipping occurs between the quartz glass plate (14) of (12b) and the quartz glass of the boat ■. Therefore, it is possible to prevent the generation of dust that would deteriorate the yield of wafers (10). Also, damage can be prevented.

Further, when positioning and supporting the boat 0), the spring (45) acts to accurately position the ball 1--) by finely adjusting the dimensional error in the longitudinal direction by expansion and contraction.

After this, move along the rail and install the boat support device (Dan).
is set at the transfer position for transferring wafers between the boat ■ and the wafer cassette. Then, at this position, the wafer (10) in boat 0 is transferred.

At this time, if the stop position of the movable plate (17) is accurately controlled, the boat (1) is positioned on the mounting table (12a) (12b), so the wafer (1) in the boat (9) is
0) can be reliably transferred by an automatic machine.

After the above operations are completed, the wafer cassette containing the new wafer (10) is then set at the transfer position. Similarly, this wafer (lO) is transferred to the boat (9).

Thereafter, the boat 0 is moved to the transfer position and the suppressing force for positioning and support is released.

Next, Uke hands boat 0 to the elevator and takes boat ■)
The operation is carried out to carry the material into the above-mentioned furnace.

At this time, the processing conditions performed in the furnace for the wafer (10) carried out and transferred from the furnace may be different from the processing conditions for the next wafer. At this time, a certain reaction gas is of course used. If the same boat is used for such different processes, the reactive gas adhering to the boat from the previous process will react with the reactive gas used in the next process, adversely affecting the wafers being processed. For this reason, the processed wafers are transferred to the wafer cassette at the transfer position. Then, replace it with a boat that corresponds to the first process or a new boat.

At the time of this boat exchange, the boat support device (Dan) that was positioning and supporting the previous boat (■), the boat (9), the a mount (12a) (12b) that is the contact part, and the contact part (42a)
(43a) also has reactive gas attached to it due to contact with the boat (9). The mounting tables (12a) (12b) and the contact portions (42a) (43a) are switched. In this switching operation, switching of the mounting table is performed by moving the mounting table (13a) (13b) relative to the cylinder (34).
is raised by the drive of the mounting table (12a) and set at a position higher than the height of the mounting table (12b).

Furthermore, switching of the abutting part is possible by rotating the rotary solenoid (41) described above, for example, to switch the abutting part to (42b) (
43b). At this time, place the mounting table (12a)
When switching from (12b) to (13a) (13b), it is set at a higher position than usual. The abutting portions (42b) and (43b) are also nitric acidized so as to abut at a higher position corresponding to this increased distance. It becomes possible to position and support the next boat under apparent conditions.

Using the mounting tables (13a) (13b) and contact parts (42b) (43b) switched in this way, the next boat is positioned and supported in the same manner as above. Next, the wafer to be processed is loaded and carried into the furnace.

After that, repeat the same process. The same process is performed for wafers with different processing conditions.

When fixing the boat (9) with the support (37) in this way, accurate positioning is required, so the lψ drive body 38 is equipped with a coil spring (45) having a desired spring force.
a) That is, supply air, for example, to the cylinder, and press the support (
37) in the direction of the boat ■. At this time, the boat
The supports (37) at both ends are positioned so that the distance between the abutting portions (42a) and (43a) or (4zb) and (43b) is slightly narrower than the distance in the longitudinal direction of the boat 0 to be positioned and supported. Set the cylinder stroke in advance. In this state, the support body (37) is driven in the direction of the boat (2). And the contact parts (42a) and (43a)
Alternatively, (42b) and (43b) are in contact with the end surface of boat 0) and sandwich the boat (2), but the above-mentioned coil The spring (45) absorbs this by stretching.

In this way, the stroke end of the cylinder is set in advance to be shorter than the longitudinal width of the boat ■. Therefore, even if the width of the boat is not constant due to boat manufacturing errors, it is possible to accurately position and support even an oddly shaped boat just by the difference in the absorption or expansion of the coil spring (45). - In the above embodiment, a cylinder was used as the driving body. However, the mechanism is not limited to the above mechanism, and similar effects can be obtained by using a solenoid, a motor, or the like.

Further, in the above embodiment, a coil spring was used as the expansion/contraction means. However, the present invention is not limited to this as long as the end of the machine is extendable and retractable.

Furthermore, in the above embodiments, support for a semiconductor wafer boat used in a semiconductor manufacturing process was explained.

However, any type of support, such as support of the supported object by a robot, can be performed in the same manner. Furthermore, the explanation has been made regarding supporting the semiconductor wafer boat from both ends in the longitudinal direction.

However, support from four directions or support from other supported bodies from multiple directions may be used. Further, the shape of the support may be either circular or spherical.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the schematic configuration of a boat support device according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the configuration of the mounting table in FIG. 1, and FIG. Explanatory diagram showing, No. 4
The figure is an explanatory diagram showing the abutting part of the other support mechanism in Figure 1, Figure 5 is an explanatory diagram showing the installation state of the expansion and contraction means in Figure 1,
The figure is an explanatory diagram for explaining the spring force of the coil spring shown in FIG. 5, and FIG. 7 is a schematic explanatory diagram of a conventional boat support device. 9...Boat, 10...Wafer, 36.
...Support mechanism, 38...Driver, 45...Coil spring.

Claims (4)

[Claims] (1) A device for supporting a supported body by applying forces in relatively opposite directions to a plurality of support mechanisms, characterized in that at least one of the support mechanisms is provided with an extensible means. (2) The support mechanism consists of a support that comes into contact with the supported object and a driver that drives this support in the supporting direction of the supported object. 2. The support device according to claim 1, further comprising an extensible means arranged in series or in parallel, and extending and contracting means parallel to the support direction between the disposed supports and the drive body. (3) The support device according to claim 1, wherein the expansion and contraction means is a coil spring. (4) The support device according to claim 1, wherein the supported object is a semiconductor wafer boat.