JP2705785B2 - Stage equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stage device for moving a movable stage along a guide, and more particularly to a semiconductor device such as a projection exposure apparatus, an electron beam drawing apparatus, or a wire bonder. The present invention relates to a stage device applied to a device. 2. Description of the Related Art Conventional stage devices include Al-based, Ti-based devices.
The movable stage portion and the transmission mechanism are formed by using a light alloy of Mg-based or Mg-based or other metal materials. [0003] However, these metallic materials have rigidity, deformation due to temperature change, abrasion resistance, and the like.
There is a problem in terms of rust prevention and the like. In particular, when the stage device is used in a vacuum atmosphere, the use of a lubricant is restricted, so that the wear resistance is further deteriorated. [0004] Maintaining the accuracy of a high-precision stage device used in the semiconductor manufacturing field is a very difficult problem in view of the aging of metal materials. The present invention has been made in view of the above circumstances, and has as its object to solve the above-mentioned problems of the prior art and to enable high-speed and high-precision movement of a movable stage. An object of the present invention is to provide a stage device that can be used without any problem even in a vacuum atmosphere. In order to solve this problem, a stage device according to the present invention comprises a base having a reference surface, a stage mounted on the base, and a stage mounted on the base. A guide section for moving in a predetermined direction in a plane parallel to a reference plane of the base, a driving source for generating a driving force for moving the stage along the guide section, An air pad for guiding the stage in a moving direction along the guide portion, and an air pad for supporting the stage in a direction perpendicular to the reference surface. And a pad, and the stage, the guide section, and the air pad are made of ceramics. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to an embodiment shown in the drawings. In FIG. 1, reference numeral 1 denotes a chuck made of alumina ceramics, which vacuum-adsorbs a silicon wafer or a sample placed thereon. Although not illustrated, the wafer chuck 1 is provided with an opening for vacuum suction and a duct connected to a vacuum pump. Reference numeral 2 denotes an alumina ceramic X stage for transferring the chuck 1 in the X direction. Numeral 3 is a sliding member made of alumina ceramics or further having a sliding surface coated with Teflon (registered trademark).
It is provided on the inner surface of the stage 2. Reference numeral 4 denotes a ceramic ball nut for applying a feeding force to the X stage 2, which is connected to the X stage 2 via a connecting member.
Built-in ceramic or non-metal ball such as ruby, sapphire. A feed ball screw 5 made of ceramics is screwed with the ball nut 4. Reference numeral 6 denotes a ceramic housing for holding the ball screw 5, in which a non-metallic bearing such as ruby or sapphire is accommodated for receiving the ball screw 5. Reference numeral 7 denotes a power transmission coupling made of ceramics. One of the couplings 7 is connected to the ball screw 5 and the other is connected to a drive shaft of a motor 8 for driving the X stage. Reference numeral 9 denotes a ceramic linear guide sliding guide for restricting the movement of the X stage 2. One surface of the sliding guide 9 contacts the rolling guide (see FIG. 2), and the other surface contacts the sliding member 3. . Reference numeral 10 denotes a ceramic Y stage, which supports the protruding portions 2 ', 2' of the X stage 2 and has an X-direction sliding guide 9 connected thereto. Reference numeral 11 denotes a sliding member made of ceramics or further coated with Teflon (registered trademark), and is provided inside the Y stage 10. Reference numeral 12 denotes a ceramic linear guide sliding guide for restricting the movement of the Y stage 10 and is coupled to a ceramic base 18. Reference numerals 13 and 14 denote ceramic housings made of ceramics for holding a ball screw 15 for feeding in the Y direction. Housings 13 and 14 accommodate bearings made of a ceramic material or a nonmetal material such as ruby or sapphire. Have been. Although not shown in the drawing, a ball nut is screwed into the ball screw 15 and fixed inside the Y stage 10. Reference numeral 16 denotes a power transmission coupling, which is made of ceramics and is coupled to a motor 17 for driving the Y stage 10. Reference numerals 10 to 22 denote ceramic sliding surfaces which are lapping and mirror-finished on a flat surface. The sliding surfaces 19 and 20 support the lower projecting portions 2 'and 2' of the X stage 2, and are provided with sliding surfaces. Reference numerals 21 and 22 support the lower projecting portions 10 'and 10' of the Y stage 10, respectively. FIGS. 2 and 3 show stages 2, 1 and 2, respectively.
FIG. 2 shows a structure of a reference example in comparison with the present invention, and FIG. 3 shows a structure according to the present invention. In FIG. 2 of the reference example, reference numeral 24 denotes a roller or needle bearing made of ceramics or a nonmetallic material. On the other hand, in FIG. 3 showing the structure of the present invention, 2
Reference numeral 5 denotes a ceramic air pad for using an air bearing. The air pad guides the X stage 2 in the moving direction (X direction) along the guide portion, and the X stage 2 moves in the vertical direction (Z direction). The air pads 25 are connected to a pneumatic duct (not shown). It should be noted that, among these members, a conventional alloy member can be used in a portion excluding the sliding surface and the rolling portion, depending on the application. In the above configuration, when the motor 8 fixed to the Y stage 10 is driven, the ball screw 5 rotates via the coupling 7 and the ball nut 4 screwed with the ball screw 5 is sent back and forth. The X stage 2 fixed thereto can be moved back and forth in the X direction. X stage 2 is flat 19
20 and 20, it is displaced in the horizontal plane without slight movement in the Z direction, and the fluctuation in the Y direction is regulated by the guide 9. On the other hand, if the motor 17 fixed to the base 18 is driven, the ball screw 15 rotates via the coupling 16 and the Y stage 10 can be moved back and forth in the Y direction. The Y stage 10 moves on planes 21 and 22 and is precisely displaced in the Y direction by being regulated by the guide 12. In this embodiment, coupling couplings 7, 1
The reason why ceramics is used as 6 is that vibration transmission from the feeder can be reduced with high rigidity and low inertia. If the entire stage is made of a ceramic material, the ceramic itself is a non-magnetic material, so that it can be used in an electron beam lithography apparatus requiring a non-magnetic stage, and there is a possibility that chemicals and the like may adhere to the stage. It is also possible to apply to a precision feeding device and a precision measuring device in a certain other field. In addition, since it can be used in a chemical solution or can be used in a vacuum, taking advantage of the advantage of no rust, it can be applied to space development. In addition, since the chuck that holds the wafer by suction is made of ceramics, the heat absorbed by the wafer during exposure is less likely to be transmitted to the stage, and the stage can be prevented from being deformed due to thermal distortion. According to the present invention, the weight of the movable portion of the stage device can be reduced without lowering its rigidity, and at the same time, the change in the ambient temperature due to the low thermal conductivity and low thermal expansion coefficient of the ceramic material. Thus, it is possible to provide a high-precision stage device that does not easily change. In addition, by adopting a non-contact air bearing and making the entire stage ceramics including the material of this air pad, the moving body is lightweight and the contact resistance at the bearing is small, resulting in a synergistic effect of two points. A small driving force and high control responsiveness can be obtained. In addition, since the moving body is lightweight, the air supply to the air bearing can be floated at a small flow rate on the stage, and the size of the air bearing can be reduced. Furthermore, since both the air pad and the guide are made of ceramics having a low coefficient of thermal expansion and a small change with time, a minute gap between the two, which is a key of the air bearing, can be maintained with extremely high precision. According to the second aspect of the present invention, in addition to the above-mentioned effects, since the chuck for holding the transferred object such as a wafer is made of ceramics, the heat absorbed by the transferred object due to exposure or the like is transmitted to the stage. It is difficult to prevent the stage from being deformed due to thermal distortion. According to the third aspect of the present invention, in addition to the above-described effects, since the base is made of ceramics, there is no relative displacement due to a difference in thermal expansion coefficient between the guide portion, the stage, and the base. A stage device with higher accuracy can be provided. According to the fourth aspect of the present invention, a two-dimensional stage device having the above effects can be provided. According to the fifth aspect of the present invention, since a semiconductor wafer can be exposed using the stage device having the above-described effects, semiconductor production with high productivity and accuracy can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing the overall configuration of a stage device according to the present invention. FIG. 2 is a sectional view showing a structure of a roller or a needle bearing as a reference example for comparison with the present invention. FIG. 3 is a sectional view showing a structure of an air bearing according to the present invention. [Description of Signs] 1 chuck 2 X stage 3 sliding member 4 ball nut 5 ball screw 6 housing 7 coupling 8 X motor 9 X guide 10 Y stage 11 sliding member 12 Y guide 13, 14 housing 15 ball screw 16 coupling 17 Y motor 18 Foundation

Claims (1)

(57) [Claims] A base having a reference surface, a stage mounted on the base, a guide portion for moving the stage in a predetermined direction in a plane parallel to the reference surface of the base, and the stage; A drive source for generating a driving force for moving the guide along the guide portion; and an air bearing for supporting and guiding the stage with air. The air bearing guides the stage in a moving direction along the guide portion. And an air pad for supporting the stage in a direction perpendicular to the reference plane, and the material of the stage, the guide portion, and the air pad is made of ceramics. Stage equipment. 2. 2. The stage device according to claim 1, wherein a chuck for holding the transferred object is provided on the stage, and the material of the chuck is ceramics. 3. 2. The stage device according to claim 1, wherein a material of said base is ceramics. 4. 2. The stage device according to claim 1, wherein the stage moves two-dimensionally in a plane parallel to the reference plane. 5. 3. The stage device according to claim 2, wherein the transferred object is a semiconductor wafer.