KR100430494B1 - Positioning apparatus having an object table without the influence of vibration and lithographic apparatus provided with the positioning apparatus - Google Patents

Abstract

Positioning device (21,31) with drive unit (147,149,151; 69,71) with an object table (1,5) movable on guides (141,65) fixed to first frame (45). The reaction force of the object tables 1, 5 on the drive units 147, 149, 151; 69, 71 generated from the driving force applied by the drive units 147, 149, 151; 69, 71 on the object tables 1, 5 is the second frame ( While exclusively transmitted to 41, the fixing parts 153, 73 of the drive units 147, 149, 151; 69, 71 are moved away from the second frame of the positioning device 21, 31 dynamically falling from the first frame 45. 41). In a particular embodiment of the positioning device 21, 31, the object table 1, 5 is a Lorentz force of the electric coil system 147, 69 of the drive units 147, 149, 151; 69, 71 and the magnet system. ) Are exclusively connected to the fixing parts 153,73 of the driving units 147, 149, 151; 69, 71. Since the reaction force is transmitted exclusively to the second frame 41, the reaction force or elastic deformation is not generated. The accuracy of the object tables 1, 5, which are located in relation to the guides 141, 65 by the drive units 147, 149, 151; 69, 71, are therefore not adversely affected by the vibrations or deformations described above. Positioning devices 21 and 31 are used in lithographic apparatus for manufacturing integrated semiconductor circuits. The lithographic apparatus has a first positioning device 21 having a substrate holder 1 movable relative to the focusing system 3 and a second positioning having a mask holder 5 movable relative to the focusing system 3. Device 31.

Description

Positioning apparatus having an object table without the influence of vibration and lithographic apparatus provided with the positioning apparatus

The present invention relates to a positioning device provided with an object table and a drive unit, and in particular, while the fixing portion of the drive unit is fixed to a second frame of the positioning device that is dynamically separated from the first frame. And at least in parallel in the X direction on a guide fixed to the first frame of the positioning device.

The present invention also provides a focusing system having a radiation source, a mask holder, a principal axis parallel to the Z direction, and a machine frame that in turn supports a substrate holder that is movable perpendicular to the Z direction by a positioning device. A lithographic apparatus provided.

The present invention also relates to a radiation source parallel to the vertical Z direction and movable by the positioning device perpendicular to the Z direction, a focusing system having a major axis parallel to the Z direction, and a further positioning device in the Z direction. A lithographic apparatus is provided with a machine frame which in turn supports a vertically movable substrate holder.

US Pat. No. 5,260,580 discloses a positioning device of the type described herein. The known positioning device comprises an object table which is guided and supported on a fixed base whose rotation is made by the first frame. The known positioning device includes a drive unit for moving the object table onto the fixed base. The drive unit includes a first linear motor in which the fixed part is supported by the fixed base and a second linear motor in which the fixed part is supported by the second frame. Since the second frame is dynamically insulated from the first frame, mechanical forces and vibrations generated in the second frame are not transmitted to the first frame. The object table of the known positioning device can be moved to a desired end position by the first linear motor since the object table can be moved to a position close to the desired end position during operation by the second linear motor. The movement of the object table by the second linear motor is usually a relatively large and speed controlled movement, during which the second linear motor exhibits a relatively large driving force on the object table. The movement of the object table by the first linear motor is a relatively small and position controlled movement, during which the first linear motor exhibits a relatively small driving force on the object table. Since the fixing part of the second linear motor is supported by the second frame which is dynamically insulated from the first frame, it is generated by the second linear motor on the object table and the relatively large reaction force generated by the object table on the second linear motor. In addition to the increased driving force, mechanical vibrations generated by the reaction force in the second frame and transmitted to the first frame, the fixed base, and the object table can be prevented. Thus, the fact that the stationary base and the object table of the known positioning device are not affected by the relatively strong vibrations generated by the second linear motor make it possible to move the object table in a fast and precise manner to the desired end position by the first linear motor. It means possible.

A disadvantage of the known positioning device is that the fixing part of the first linear motor is supported by the fixing base on which the object table is guided. As a result, the reaction force generated by the object table on the first linear motor and the increased driving force generated by the first linear motor on the object table are transmitted to the fixed base and the first frame. Since the movement of the object table by the first linear motor is relatively small, the value of the reaction force becomes relatively small, but has a relatively large frequency. In particular, if the movement of the object table to the desired end position occurs in a relatively short time, the frequency of the reaction force can be compared with the natural frequency of an ordinary frame such as the first frame of the known positioning device. Thus, the reaction force of the first linear motor causes resonance in the first frame, so that a relatively strong mechanical vibration is generated in the first frame, the fixed base, and the object table, resulting in poor positioning accuracy of the first linear motor and the desired end. Extend the time to reach the location.

The invention will be described in detail below with reference to the accompanying drawings.

1 is a perspective view of a lithographic apparatus according to the present invention.

2 is a diagram of the lithographic apparatus of FIG. 1.

3 is a perspective view of a base and a substrate holder of the lithographic apparatus of FIG.

4 is a plan view of the base and the substrate holder of FIG.

5 is a plan view of the mask holder of the device of FIG.

6 is a cross-sectional view taken along the line VI-VI of FIG. 5;

7 is a cross-sectional view of the dynamic insulator of the device of FIG. 1.

8 is a cross-sectional view taken along the line VIII-VIII in FIG. 7.

9 is a schematic representation of the force actuation system of the lithographic apparatus of FIG. 1.

It is an object of the present invention to provide a positioning device which supplements as much as possible the disadvantages described above with respect to known positioning devices. The present invention is characterized in that, in order to achieve the above object, the reaction force exerted by the object table on the drive unit during operation and generated from the driving force exerted by the drive unit on the object table is transferred exclusively to the second frame. Since the reaction force is transmitted exclusively to the second frame, mechanical vibration is generated in the second frame only by the reaction force. Since the second frame is dynamically insulated from the first frame, and mechanical vibrations generated in the second frame by the reaction force are not transmitted to the first frame, the first frame, the guide, and the object table are applied to the reaction force. It is not affected by mechanical vibrations caused by it. Thus, the first frame does not cause resonance by the relatively high frequency component of the reaction force, which occurs when the object table is precisely moved by the drive unit to the desired end position. The fact that the first frame is not affected by the mechanical vibration generated by the reaction force is improved not only by the positioning precision and the time required for positioning due to the absence of mechanical vibration in the first frame, but also by the desired end position. The required time can be further reduced due to the relatively high frequency of allowable driving force during positioning of the object table.

A particular embodiment of the positioning device according to the invention is exclusively connected to the fixture of the drive unit by the Lorentz force of the electric coil system and the magnet system of the drive unit during operation of the object table. Since the object table is exclusively connected to the fixing unit of the drive unit by the Lorentz force, the object table is physically insulated from the fixing unit of the driving unit, that is, the physical contact or connection between the object table and the fixing unit of the driving unit is Does not happen. In the present embodiment, the Lorentz force includes the driving force generated by the driving unit on the object table. Since the object table is physically insulated from the fixed part of the drive unit, the mechanical vibration generated in the fixed part of the drive unit is transmitted to the object table and the first frame via the drive unit by the reaction force generated by the Lorentz force. Is prevented.

In another embodiment of the positioning device according to the invention, the magnet system and the electric coil system are provided with a second linear motor having a fixed part fixed to the second frame and a movable part moving parallel to the X direction on the guide of the fixed part. Belonging to the first linear motor of the drive unit, wherein the magnet system of the first linear motor is fixed to the object table, and the electrical coil system of the first linear motor is fixed to the movable portion of the second linear motor. In the above embodiment, the object table is moved to a position close to the desired end position by a relatively large distance parallel to the X direction by the second linear motor, and then the object table is suitable for this purpose by the Lorentz of the first linear motor. By virtue of the force, the position of the second linear motor relative to the movable part is substantially constant. Thereafter, the object table can be moved to the desired end position by the first linear motor, wherein the movable portion of the second linear motor is in a certain position with respect to the stationary part. Since the object table needs to travel a relatively small distance only during positioning by the first linear motor to the end position, the writing system and the electric coil system of the first linear motor need only have relatively small dimensions. The reaction force on the stationary portion of the second linear motor generated from the driving force generated by the second linear motor is transmitted directly to the second frame.

The reaction force on the electrical coil system of the first linear motor generated from the Lorentz force generated by the first linear motor is transmitted to the second frame via the movable part, the guide, and the fixing part of the second linear motor.

In another embodiment of the positioning device according to the present invention, the fixing part fixed to the movable part of the second linear motor, in which the driving unit can be moved parallel to the Y direction perpendicular to the X direction, on the guide of the fixing part of the third linear motor. And a third linear motor provided, wherein the electric coil system of the first linear motor is fixed to the movable portion of the third linear motor. In the embodiment of the positioning device, for example, the object table is moved parallel to the X and Y directions because the guide of the object table is a surface extending parallel to the X and Y directions. The object table is positioned at the desired end position by the first linear motor because the object table is capable of moving a relatively large distance parallel to the X and Y directions to a position close to the desired end position by the second and third linear motors. Can be set. Allowing the object table to move a relatively small distance parallel to the X and Y directions can be achieved through proper design of the magnetic system and the electric coil system of the first linear motor. The reaction force on the stationary part of the second motor caused by the driving force generated by the second linear motor is transmitted directly to the second frame and the reaction force on the stationary part of the third motor caused by the driving force generated by the third linear motor. The force is transmitted to the second frame via the movable part, the guide and the fixed part of the second linear motor. The reaction force on the electrical coil system of the first linear motor generated from the Lorentz force generated by the first linear motor is determined by the second frame via the moving parts, guides, and fixing parts of the second and third linear motors in that order. Is passed on.

The positioning device of another embodiment according to the invention is provided with a force actuator system which applies a compensating force on the first frame during operation and is controlled by an electrical control unit, the compensating force being in a direction opposite to the machine moment direction of gravity. It has a mechanical moment with respect to the reference point of the first frame having a value equal to the value of the mechanical moment of gravity occurring on the object table with respect to the reference point. The object table is placed in the guide of the first frame having a bearing force determined by the gravity generated thereon. When the object table is moved, the point of application of the bearing force on the guide is moved relative to the first frame. The use of a force actuator results in no vibration or shaking in the first frame as a result of the relatively large and rapid movement of the application table and the object table relative to the first frame. The control unit controls the compensating force of the force actuator system as a function of the position of the object table relative to the first frame. Due to the compensation force, the movable object table has a so-called virtual gravity center having a constant position with respect to the first frame. Thus, in this embodiment, the first frame is not only affected by mechanical vibrations caused by the reaction force of the drive unit of the object table, but also mechanically generated by the actual gravity center movement of the object table associated with the first frame. It is not affected by vibration. The positioning precision of the positioning device and the time required for the object table to move to the desired end position are further improved by not doing the above.

In another embodiment of the positioning device according to the invention, the force actuator system exerts a compensating force on the first frame in parallel to the vertical direction, and the object table is movable in parallel in the horizontal direction. The force actuator system applies a compensating force parallel to the vertical direction on the first frame and fails to generate a compensating force in the driving direction of the object table on the first frame, so that the mechanical of the first frame oriented parallel to the driving direction is In addition to the means associated with the reaction force of the drive unit of the object table in order to prevent vibration, no additional means is required. The vertical vibration of the first frame is prevented when the value of the compensating force of the force actuator system remains constant and the point of application of the compensating force on the first frame is moved as a function of the position of the object table. The shift of the point of application of the compensating force of the force actuator system is achieved, for example, through the use of a force actuator system equipped with at least two insulated force actuators, the compensating force of the force actuator being a constant value insulated force actuator. Individually controlled as a function of the position of the object table as the sum of the compensation forces.

In another embodiment of the positioning device according to the invention, the force actuator systems comprise three force actuators arranged mutually in a triangular shape and generating compensating forces in a vertical direction parallel to the first frame, the object table being horizontal It is movable in parallel to the horizontal Y direction parallel to the X direction and perpendicular to the X direction. The use of a force actuator system with three force actuators arranged in a triangular shape not only prevents mechanical vibrations on the first frame resulting from the movement of the object table parallel to the X direction, but also of the object table parallel to the Y direction. Mechanical vibration of the first frame resulting from the movement can be prevented. Since the sum of the compensating forces of the respective force actuators is kept constant during operation, no vertical vibration of the first frame is generated. In addition, the triangular arrangement of the force actuators makes the force actuator system stable operation.

In another embodiment of the positioning device according to the invention, the force actuator system is integrated into the system of the dynamic insulator so that the first frame is connected to the base of the positioning device. Dynamic insulators are dampers with relatively low mechanical stiffness, whereby the first frame is dynamically insulated from the base. Since the damper has a relatively low mechanical stiffness, mechanical vibrations such as floor vibrations or vibrations of the second frame are generated at the base if the vibrations of the second frame fixed to the base are not transmitted to the first frame. The integration of the dynamic insulator system and the force actuator system provides a particularly compact and simple structured positioning device.

In another embodiment of the positioning device according to the invention, the compensating force exclusively comprises the force of Lorentz of the electric coil system and the magnet system of the force actuator system. The force actuator system includes a part fixed to the first frame and a part fixed to the base of the positioning device. Since the compensating force of the force actuator system exclusively includes Lorentz's force, the part of the force actuator system is physically insulated, ie no physical contact or connection between the parts occurs. Thus, for example, if the vibration of the second frame fixed to the base is transmitted to the first frame and the object table via the force actuator system, the mechanical appearing on the base of the positioning device such as vibration or floor vibration of the second frame Vibration can be prevented.

A lithographic apparatus equipped with a movable substrate holder similar to that described herein is disclosed in EP-A-0 498 496. Known lithographic apparatuses are used in the manufacture of integrated semiconductor circuits by optical lithography processes. The focusing system is an optical lens system by means of a partial pattern of integrated semiconductor circuits which is projected on a reduced scale on a semiconductor substrate located on the substrate holder of the lithographic apparatus and formed on a mask located on the mask holder of the lithographic apparatus, which is known The radiation source of the lithographic apparatus is a light source. The semiconductor substrate includes a large number of fields in which the same semiconductor circuit is provided. The individual fields of the semiconductor substrate are continuously exposed for the above purpose, the semiconductor substrate has a constant position in relation to the focusing system and the mask during the exposure of the individual fields, and the next field of the semiconductor substrate is It is moved to a position associated with the focusing system by the positioning device of the substrate holder. Since the process is repeated many times with different masks provided with different partial patterns, an integrated semiconductor circuit having a relatively complicated structure can be manufactured. The structure of the integrated semiconductor circuit has fine dimensions in the range of micron or less. The partial patterns formed on the continuous mask should be projected onto the field of the semiconductor substrate with a precision in the range of micron or less with respect to each other. The semiconductor substrate should be positioned relative to the focusing system and the mask by the positioning device of the substrate holder with precision in the submicron range. Moreover, to reduce the time required for the manufacture of semiconductor circuits, the semiconductor substrate must be moved at a relatively high speed between two successive exposure steps and positioned in relation to the mask and focusing system with the desired precision.

In the lithographic apparatus provided with the movable substrate holder according to the present invention, the positioning device of the substrate holder is a positioning device according to the present invention, and the first frame of the positioning device of the substrate holder belongs to the mechanical frame of the lithographic apparatus. The second frame of the positioning device of the substrate holder belongs to the force frame of the lithographic apparatus which is dynamically insulated from the machine frame. Thus, since the relatively large reaction force exerted by the substrate holder on the positioning device during the relatively rapid movement between the two exposure steps is transmitted to the force frame of the lithographic apparatus, the lithographic apparatus supporting the mask holder, the focusing system and the substrate holder The machine frame is not affected by mechanical vibrations generated by the reaction forces in the force frame. The precision with which the substrate holder is positioned in relation to the mask holder and the focusing system and the time required to position the substrate holder to the desired precision are not adversely affected by mechanical vibrations.

Lithographic apparatus having a displaceable mask holder and a displaceable substrate holder of the kind mentioned at the outset are known from US Pat. No. 5,194,893. In this known lithographic apparatus, the semiconductor substrate under manufacture is not in a constant position relative to the focusing system and the mask during exposure of a single field of the semiconductor substrate, but instead the semiconductor substrate and mask are respectively positioned during the exposure of the mask holder positioning device and the substrate. By the positioning device of the holder it is displaced synchronously with respect to the focusing system parallel to the X direction perpendicular to the Z direction. In this way, the pattern on the mask is scanned parallel to the X direction and synchronously projected onto the semiconductor substrate. The maximum area of the mask that can be projected onto the semiconductor substrate by the focusing system is less limited by the hole size of the focusing system. Since the dimensions of the direct semiconductor circuit to be manufactured are in the sub-micron range, the semiconductor substrate and the mask must be displaced with a submicron range precision for the focusing system during exposure. In order to reduce the time required for the manufacture of semiconductor circuits, the semiconductor substrate and the mask must be displaced and positioned relative to one another at relatively high speeds during exposure. Since the pattern on the mask is projected on a reduced scale on the semiconductor substrate, the speed and distance at which the mask is displaced is greater than the speed and distance at which the semiconductor substrate is displaced, and the ratio between both distances and the speed between the speeds is reduced in focusing system. Same as the argument.

According to the invention, a lithographic apparatus having a displaceable substrate holder and a displaceable mask holder is characterized in that the positioning device of the mask holder is a positioning device according to the invention, wherein the first frame of the positioning device of the mask holder is It belongs to the machine frame of the lithographic apparatus, and the second frame of the positioning device of the mask holder belongs to the force frame of the lithographic apparatus which is dynamically insulated from the machine frame.

A particular embodiment of the lithographic apparatus having a displaceable substrate holder according to the invention is characterized in that the mask holder is displaceable perpendicularly to the Z direction by the positioning apparatus according to the invention. One frame belongs to the machine frame of the lithographic apparatus, and the second frame of the positioning device of the mask holder belongs to the force frame of the lithographic apparatus.

The relatively large reaction forces exerted on the positioning device of the mask holder by the mask holder as a result of the acceleration and relatively high speed of the mask holder during exposure of the semiconductor substrate are thus transmitted to the force frame of the lithographic apparatus. The mechanical frame of the lithographic apparatus supporting the substrate holder is thus not affected by mechanical vibrations generated by the reaction force of the force frame. The precision of the movement of the substrate holder and the mask holder relative to the focusing system during exposure of the semiconductor substrate is thus not adversely affected by the mechanical vibration.

In another embodiment of the lithographic apparatus according to the invention, the positioning device of the substrate holder and the mask holder generates a compensating force on the machine frame of the lithographic apparatus during operation, and has a coupling force actuator system controlled by the electrical control unit, The compensating force is a mechanical moment with respect to the reference point of the machine frame, which is equal to the sum of the mechanical moments of gravity present on the substrate holder with respect to the reference point, and the mechanical moment of gravity present on the mask holder with respect to the reference point, and the sum of the mechanical moment. It has a direction opposite to the direction of. The use of the coupling force actuator system prevents the machine frame of the lithographic apparatus from vibrating or shaking as a result of the relatively fast movement of the mask holder and the substrate holder relative to the machine frame during exposure of the semiconductor substrate. The control unit controls the compensating force of the coupling force actuator system as a function of the position of the substrate holder and the position of the mask holder relative to the machine frame. Thus, the precision with which the mask holder and the substrate holder are positioned relative to the focusing system during exposure of the semiconductor substrate is prevented from being adversely affected by mechanical vibrations caused by the movement of the center of gravity of the mask holder and the substrate holder relative to the machine frame. . The lithographic apparatus according to the invention is located on the base of a lithographic apparatus on which a force frame is located, by means of three dynamic insulators in which the machine frame is arranged in a triangle with each other, and the coupling force actuator system is each integrated with one corresponding dynamic insulator It is characterized by including three separate force actuators. For example, the dynamic insulator is a damper with relatively low mechanical stiffness, by which the mechanical frame is dynamically isolated from the base. Due to the relatively low mechanical stiffness of the damper, mechanical vibrations, such as mechanical vibrations of the frame due to the reaction forces of the positioning device of the mask holder and the substrate holder, are not transmitted to the mechanical frame. The integration of the dynamic insulator system and the force actuator system makes the structure of the lithographic apparatus particularly compact and simplified. The triangular configuration of the insulator provides a stable support for the machine frame.

The lithographic apparatus according to the invention shown in FIGS. 1 and 2 is used for the manufacture of integrated semiconductor circuits by an optical lithographic apparatus process. As schematically shown in FIG. 2, the lithographic apparatus is provided with a substrate holder 1, a focusing system 3, a mask holder 5, and a radiation source 7 in turn when viewed parallel to the vertical Z direction. The lithographic apparatus shown in FIGS. 1 and 2 is an optical lithographic apparatus in which the radiation source 7 comprises a light source 9, a diaphragm 11, and mirrors 13, 15. The substrate holder 1 comprises a support surface 17 which extends perpendicular to the Z direction and on which the semiconductor substrate 19 can be placed, which is perpendicular to the Z direction by the first positioning device 21 of the lithographic apparatus. It is movable relative to the focusing system 3 in parallel with the X direction and the Y direction perpendicular to the X and Z directions. The focusing system 3 is an imaging or projection system and comprises an optical lens system 23 having an optical principal axis 25 parallel to the Z direction and an optical reduction element, for example four or five. The mask holder 5 comprises a support surface 27 perpendicular to the Z direction and on which the mask 29 is placed, which is in the X direction with respect to the focusing system 3 by the second positioning device 31 of the lithographic apparatus. It is movable parallel to. Mask 29 includes a pattern or partial pattern of an integrated semiconductor circuit. During operation, the light beam 33 from the light source 9 passes through the mask 29 through the diaphragm 11 and the mirrors 13, 15 and is focused on the semiconductor substrate 19 by the lens system 23. The pattern shown on the mask 29 is projected on the semiconductor substrate 19 at a reduced scale. The semiconductor substrate 19 includes a plurality of individual fields 35 provided with the same semiconductor circuit. For this purpose, the field 35 of the semiconductor substrate 19 is continuously exposed through the mask 29, and the next field 35 is positioned relative to the focusing system 3 after every exposure of the individual fields 35. Here, the substrate holder 1 is moved parallel to the X direction or the Y direction by the first positioning device 21. This process is repeated many times, each time with a different mask, thereby producing a relatively complex integrated circuit with a layered structure.

As shown in FIG. 2, the semiconductor substrate 19 and the mask 29 are focused by the first and second positioning devices 21 and 31 in parallel to the X direction during the exposure of the individual fields 35. Move synchronously with respect to Therefore, the pattern shown on the mask 29 is scanned parallel to the X direction and simultaneously projected onto the semiconductor substrate 19. In this way, as clearly shown in FIG. 2, the maximum width B of the mask 29 guided parallel to the Y direction that can be projected onto the semiconductor substrate 19 by the focusing system 3 is It is limited exclusively by the diameter D of the hole 37 of the focusing system 3 schematically shown in FIG. 2. The allowable length L of the mask 29, which can be projected onto the semiconductor substrate 19 by the focusing system 3, is larger than the diameter D which follows the so-called "step and scan" method. In this projection method, the maximum area of the mask 29 that can be projected on the semiconductor substrate 19 by the focusing system 3 is limited by the diameter D of the hole 37 of the focusing system 3. Therefore, it is less than in conventional projection methods that follow the so-called "step and repeat" principle, which is used for example in a lithographic apparatus known in EP-A-0 498496, where a mask and a semiconductor substrate are focused during exposure of the semiconductor substrate. In a fixed position relative to the system, since the pattern shown on the mask 29 is projected on the semiconductor substrate 19 in a reduced size, the length L and the width B of the mask 29 correspond to a corresponding size. Beam length L 'and width B' of field 35 on semiconductor substrate 19 Large, the ratio between the lengths L, L 'and the width B, B' is the same as the optical reducing element of the focusing system 3. Consequently, also the distance the mask 29 is moved during exposure. And the ratio between the distance that the semiconductor substrate 19 moves during exposure and the speed at which the mask 29 moves during exposure and the speed at which the semiconductor substrate 19 moves during exposure are determined by the focusing system 3. The same as the optical reducing element In the lithographic apparatus shown in Fig. 2, the directions in which the semiconductor substrate 19 and the mask 29 move during exposure are opposite to each other Various focusing in which the lithographic apparatus does not project the mask pattern upside down The direction may also be the same if the system is included.

Integrated semiconductor circuits manufactured with lithographic apparatus are structures with fine dimensions in the sub-micron range. Since the semiconductor substrate 19 is continuously exposed through a number of different masks, the pattern appearing on the mask must be projected onto the semiconductor substrate 19 with respect to each other with a submicron range, even nanometer range precision. Therefore, during the exposure of the semiconductor substrate 19, the semiconductor substrate 19 and the mask 29 must be moved relative to the focusing system 3 with the above precision, so that the positions of the first and second positioning devices 21, 31 are maintained. Relatively high requirements are imposed on set accuracy.

As shown in FIG. 1, the lithographic apparatus has a base 39 lying on a horizontal bottom surface. The base 39 forms part of the force frame 41 that includes a vertically fairly rigid metal column 43 that is secured to the base 39. The lithographic apparatus also comprises a machine frame 45 having a triangular and fairly rigid metal main plate 47 which extends transversely to the optical main axis of the focusing system 3 and is provided with a central light path opening not visible in FIG. 1. The main plate 47 includes three corner portions 49 placed on three dynamic insulators 51 which are fixed on the base 49, which will be described in detail below. Only two corner portions 49 of the main plate 47 and two dynamic insulators 51 can be seen in FIG. 1, and all three dynamic insulators 51 can be seen in FIGS. 3 and 4. The focusing system 3 has a mounting ring 53 near the lower side, by which the focusing system 3 is fixed to the main plate 47. The machine frame 45 also includes a vertical and fairly rigid metal column 55 fixed on the main plate 47. Near the upper side of the focusing system 3, there is also a support member 57 for the mask holder 5, which also belongs to the machine frame 45 and is fixed to the column 55 of the machine frame 45. do. Also belonging to the machine frame 45 are three vertical suspension plates 59 fixed to the lower side of the main plate 47 adjacent to each of the three corner portions 49. Only two suspension plates 59 are partially visible in FIG. 1 and all three suspension plates 59 are visible in FIGS. 3 and 4. As shown in FIG. 4, the horizontal support plate 61 for the substrate holder 1 also belongs to the machine frame 45 which is fixed to the three suspension plates 59. The support plate 61 is not visible in FIG. 1 but only partially in FIG. 3.

From the above, the machine frame 45 supports the main part of the lithographic apparatus, i.e., the substrate holder 1, the focusing system 3 and the mask holder 5 in parallel to the vertical Z direction. As will be explained in more detail below, the dynamic insulator 51 has a significantly low mechanical stiffness. Therefore, no mechanical vibrations appearing at the base 39, such as floor vibrations, for example, are transmitted to the mechanical frame 45 through the dynamic insulator 51. As a result, the positioning devices 21 and 31 are not adversely affected by the mechanical vibrations presented in the base 39. The function of the force frame 41 will be described in more detail below.

As shown in FIGS. 1 and 5, the mask holder 5 comprises a block 63 with a support surface 27. The support member 57 for the mask holder 5 belonging to the machine frame 45 extends in parallel with the central light path opening 64 as seen in FIG. 5 and in the X direction lying in a common plane perpendicular to the Z direction. Two planar guides 65. The block 63 of the mask holder 5 has air having a degree of freedom of movement parallel to the X direction and a direction parallel to the Y direction, and a degree of freedom of rotation about the axis of rotation 67 of the mask holder 5 guided parallel to the Z direction. Guided onto the planar guide 65 of the support member 57 by a static bearing (not shown).

As further shown in FIGS. 1 and 5, the second positioning device 31 for moving the mask holder 5 comprises a first linear motor 69 and a second linear motor 71. . A second linear motor 71 of the type known in the art comprises a fixture 73 fixed to the column 43 of the force frame 41. The fixing portion 73 includes a guide 75 extending in parallel to the X direction in which the movable portion 77 of the second linear motor 71 can move. The movable portion 77 includes a connecting arm 79 extending parallel to the Y direction, to which the electric coil holder 81 of the first linear motor 69 is fixed. The permanent magnet holder 83 of the first linear motor 69 is fixed to the block 63 of the mask holder 5. The first linear motor 69 is of the kind known from EP-B-0 421 527. As shown in FIG. 5, the coil holder 81 of the first linear motor 69 has four electric coils 85, 87, 89, 91 extending parallel to the Y direction and parallel to the X direction. An electric coil 93 is included. Coils 85,87,89,91,93 are shown approximately in dashed lines in FIG. The magnetic holder 83 is composed of ten pairs of permanent magnets 95a, 95b, 97a, 97b, 99a, 99b, 101a, 101b, 103a, 103b, and (shown by dashed lines in FIG. 5). 105a, 105b, 107a, 107b, 109a, 109b, 111a, 111b, 113a, 113b. The electrical coils 85 and permanent magnets 95a, 95b, 97a, 97b belong to the first X motor 115 of the first linear motor 69, while the coils 87 and magnets 99a, 99b) and 101a and 101b belong to the second X motor 117 of the first linear motor 69, and the coil 89 and the magnets 103a and 103b and 105a and 105b are the first linear motor. Belonging to the third X motor 119 of 69, and the coil 91 and the magnets 107a, 107b, 109a, 109b belong to the fourth X motor 121 of the first linear motor 69. The coil 93, the magnets 111a, 111b, and 113a, 113b belong to the Y motor 123 of the first linear motor 69. 6 is a cross-sectional view of the first X motor 115 and the second X motor 117. As shown in FIG. 6, the coil holder 81 includes a first portion 125 of the magnetic holder 83 including magnets 95a, 97a, 99a, 101a, 103a, 105a, 107a, 109a, 111a, 113a. ) And the second portion 127 of the magnetic holder comprising magnets 95b, 97b, 99b, 101b, 103b, 105b, 107b, 109b, 111b, 113b. In addition, as shown in FIG. 6, the magnet pairs 95a and 95b of the first X motor 115 and the magnet pairs 99a and 99b of the second X motor 117 are magnetized parallel to the positive Z direction. The magnet pairs 97a and 97b of the first X motor 115 and the magnet pairs 101a and 101b of the second X motor 117 are magnetized in parallel to opposite negative Z directions. The magnet pairs 103a and 103b of the third X motor 119, the magnet pairs 107a and 107b of the fourth X motor 121, and the magnet pairs 111a and 111b of the Y motor 123 are positive Z. While magnetized in parallel to the direction, the magnet pairs 105a and 105b of the third X motor 119, the magnet pairs 109a and 109b of the fourth X motor 121 and the magnet pairs 113a of the Y motor 123. 113b) is magnetized parallel to the negative Z direction. In addition, the magnets 97a and 97a of the first X motor 115 are interconnected by the magnetic closing yoke 129, and the magnets 95b and 97b, the magnets 99a and 101a and the magnets 99b and 101b are The magnetic closing yoke 131, the magnetic closing yoke 133, and the magnetic closing yoke 135 are interconnected, respectively. The third X motor 119, the fourth X motor 121, and the Y motor 123 are connected to each other. A similar magnetic closure yoke is provided. During operation, when current flows through the coils 85, 87, 89, 91 of the X motors 115, 117, 119, 121, the coils and magnets of the X motors 115, 117, 119, 121 exert a Lorentz force parallel to the X direction. When the current through the coils 85,87,89,91 takes the same value and the same direction, the mask holder 5 is displaced parallel to the X direction by the Lorentz force, and the mask holder 5 is the coil 85 If the current through 87 has the same value but takes a direction opposite to the current through the coils 89 and 91, it is rotated about the rotation axis 67. Since the coil and the magnet of the Y motor 123 exert a Lorentz force parallel to the Y direction as a result of the current through the coil 93 of the Y motor 123, the mask holder 5 is displaced parallel to the Y direction. do.

During exposure of the semiconductor substrate 19, the mask holder 5 must be displaced with respect to the focusing system 3 in parallel with the X direction at high positioning accuracy and relatively large intervals. To achieve this, the coil holder 81 of the first linear motor 69 is displaced parallel to the X direction by the second linear motor 71, and the predetermined displacement of the mask holder 5 is determined by the second linear motor ( Almost accomplished by 71, the mask holder 5 is moved along the movable portion 77 of the second linear motor 71 by the appropriate Lorentz force of the X motors 115,117,119,121. Due to this displacement of the mask holder 5 relative to the focusing system 3, the Lorentz force of the motors 115, 117, 119, 121 is controlled by an appropriate control system during the displacement of the mask holder 5. Although not shown in detail in the drawings, the position control system includes a known laser interferometer used to measure the position of the mask holder 5 relative to the focusing system 3, and thus the desired position in the sub-micron or nanometer range. Setting precision is achieved. During exposure of the semiconductor substrate 19, the first linear motor 69 not only controls the displacement of the mask holder 5 parallel to the X direction, but also the rotation angle of the mask holder 5 with respect to the rotation axis 67 and the Y. The position of the mask holder 5 is controlled parallel to the direction. Since the mask holder 5 is located parallel to the Y direction and rotated about the rotation axis 67 by the first linear motor 69, the displacement of the mask holder 5 is the positioning accuracy of the first linear motor 69. Parallel to the X direction determined by. The deviation from the parallelism of the guide 75 of the second linear motor 71 with respect to the X direction can be compensated through the displacement of the mask holder 5 parallel to the Y direction. The desired displacement of the mask holder 5 is almost achieved only by the second linear motor 71, and since a particularly high requirement is not imposed on the parallelism of the guide 75 in the X direction, a relatively simple conventional one-dimensional linear motor Can be used as the second linear motor 71, whereby the mask holder 5 can be displaced at relatively large intervals with relatively low precision. The desired precision of the displacement of the mask holder 5 displaces the mask holder 5 by the first linear motor 69 at a relatively small interval relative to the movable portion 77 of the second linear motor 71. The first linear motor 69 is constructed with a relatively small number of dimensions because the distance between the mask holder 5 and the movable portion 77 of the second linear motor 71 is small. The electrical resistance loss of the electrical coil of the first linear motor 69 is minimized.

As described above, the fixing portion 73 of the second linear motor 71 is fixed to the force frame 41 of the lithographic apparatus. Thus, the reaction force generated from the driving force of the second linear motor 71 applied to the movable portion 77 and applied by the movable portion 77 of the second linear motor 71 on the fixed portion 73 to the force frame 41. Delivered. Since the coil holder 81 of the first linear motor 69 is fixed to the movable part 77 of the second linear motor 71, it is generated by the mask holder on the movable part 77 and applied on the mask holder 5. The reaction force generated from the Lorentz force of the first linear motor 69 is transmitted to the force frame 41 via the fixed portion 73 and the movable portion 77 of the second linear motor 71. Thus, the reaction force generated by the second positioning device 31 with the driving force exerted on the mask holder 5 and exerted during operation by the mask holder 5 on the second positioning device 31 is the force It is exclusively introduced into the frame 41. The reaction force is a high frequency component resulting from a relatively low displacement moved by the first linear motor 69 as well as a low frequency component resulting from a relatively large displacement of the second linear motor 71 to achieve the desired positional accuracy. Has Since the frame 41 is relatively rigid and located on a solid base, mechanical vibrations due to the low frequency component of the reaction force of the force frame 41 are negligibly small. The high frequency component of the reaction force has a small value, but typically has a frequency that can be compared to the resonant frequency characteristics of a frame of the same type as the force frame 41 used. As a result, the high frequency component of the reaction force causes a negligible high frequency mechanical vibration of the frame 41. The force frame 41 is dynamically insulated from the machine frame 45, ie mechanical vibrations having a frequency above a predetermined threshold of 10 Hz, for example, cause the machine frame 45 to pass through the low frequency dynamic insulator 51. Since it is exclusively coupled to the force frame 41, it is not transmitted to the machine frame 45. Thus, the high frequency mechanical vibration generated in the force frame 41 by the reaction force of the second positioning device 31 is not transmitted to the mechanical frame 45 similar to the floor vibration described above. Since the plan guide 65 of the support member 57 extends perpendicular to the Z direction and the driving force generated by the second positioning device 31 on the mask holder 5 is directed perpendicular to the Z direction, the driving force is There is no mechanical vibration in the machine frame 45. Furthermore, the mechanical vibrations present in the frame 41 may be characterized in that the mask holder 5 is driven by the Lorentz force of the magnetic coil system and the electric coil system of the first linear motor 69, as described above. Exclusively coupled to the movable portion 77 and physically insulated from the movable portion of the second linear motor 71 away from the Lorentz force, through the movable portion 77 and the fixed portion 73 of the second linear motor 71. It cannot be delivered to the machine frame 45. Thus, as described above, the machine frame 45 is substantially unaffected from deformation and mechanical vibration by the reaction force and driving force of the second positioning device 31. This advantage is further described below.

As shown in FIGS. 3 and 4, the substrate holder 1 comprises a block 137 with a support surface 17 and a gas statically supported foot 139 provided with a gas static bearing. The substrate holder 1 is guided on the upper surface 141 which extends vertically in the Z direction of the rigid support 143 provided on the support plate 61 of the machine frame 45 by the foot hydrostatically supported foot 139. And rotational degrees of freedom with respect to the axis of rotation 145 of the substrate holder 1 parallel to the Z direction and displacement degrees of freedom parallel to the Y direction and parallel to the X direction.

As shown in FIGS. 1, 3, and 4, the positioning device 21 of the substrate holder 1 includes a first linear motor 147, a second linear motor 149, and a third linear motor 151. do. The second linear motor 149 and the third linear motor of the positioning device 21 are of the same kind as the second linear motor of the positioning device 31. The second linear motor 149 includes a fixing portion 154 fixed to the arm 155 fixed to the base 39 belonging to the force frame 41. The fixing part 153 includes a guide 157 extending in parallel in the Y direction, such that the movable part 159 of the second linear motor 149 may be displaced. The fixing part 161 of the third linear motor 151 has a guide 163 disposed in the movable part 159 of the second linear motor 149 and extending in parallel to the X direction, and thus the third linear motor ( Movable portion 65 of 151 may be displaced. As shown in FIG. 4, the movable portion 165 of the third linear motor 151 includes a coupling portion 167 to which the electric coil holder 169 of the first linear motor 147 is fixed. The first linear motor 147 of the first positioning device 21 is the first linear motor 69 of the second positioning device 31 of the kind known from EP-B-0 421 527. Since the first linear motor 69 of the second positioning device 31 has been described in detail above, the detailed description of the first linear motor 147 of the first positioning device 21 is omitted. The substrate holder 1 is exclusively coupled to the movable portion 165 of the third linear motor 151 by the Lorentz force perpendicular to the Z direction during operation. However, the difference between the first linear motor 147 of the first positioning device 21 and the first linear motor 69 of the second positioning device 31 is that Whereas one linear motor 147 includes a comparable power rating of the X motor and the Y motor, the single Y motor 123 of the first linear motor 69 of the second positioning device 31 is an X motor ( It has a relatively low power rating compared to the power rating of 115,117,119,121. This means that the substrate holder 1 can be parallel to the X direction as well as parallel to the Y direction by the first linear motor 147 at relatively large intervals. Furthermore, the substrate holder 1 can be rotated about the rotation axis 145 by the first linear motor 147.

During exposure of the semiconductor substrate 19, the substrate holder 1 must be displaceable with respect to the focusing system 3 in parallel to the X direction with high positional accuracy, the substrate holder 1 being next to the semiconductor substrate 19. The field 35 is moved in parallel with respect to the X or Y direction when placed against the focusing system for exposure. In order to place the substrate holder 1 parallel to the X direction, the coil holder 169 of the first linear motor 147 is moved in parallel to the X direction by the third linear motor 151, and the substrate holder 1 The desired displacement of c) is approximated by a third linear motor 151 and the substrate holder 1 is a suitable Lorentz of the first linear motor 147 relative to the movable portion 165 of the third linear motor 151. Works by force. In a similar manner, the desired displacement of the substrate holder 1 parallel to the Y direction is approximated by the displacement of the coil holder 169 parallel to the Y direction by the second linear motor 149, where the substrate holder 1 is It is operated by the appropriate Lorentz force of the first linear motor 147 relative to the movable portion 165 of the third linear motor 151. In a similar manner, the displacement of the substrate holder 1 parallel to the Y direction is approximated by the displacement of the coil holder 169 parallel to the Y direction by the second linear motor 149, and the substrate holder 1 It is operated by the appropriate Lorentz force of the first linear motor 147 against the movable portion 165 of the three linear motors 151. The desired displacement of the substrate holder 1 parallel to the X or Y direction is controlled by the Lorentz of the first linear motor 147 which is controlled during displacement of the substrate holder 1 by the position control system of the lithographic apparatus mentioned above. Force is achieved to have positioning accuracy in the sub-micron or nanometer range. Since the desired displacement of the substrate holder 1 only needs to be approximated by the second linear motor 149, therefore, the positioning accuracy of the second third linear motors 149 and 151 is not particularly largely required. The second linear motor 149 and the third linear motor 151 are relatively simple, conventional one-dimensional linear motors, as in the second linear motor 71 of the second positioning device 31, thereby providing a substrate. The holder 1 can be displaced with relatively low accuracy a relatively large distance in parallel to the X direction or the Y direction, respectively. The desired accuracy of the displacement of the substrate holder 1 is performed such that the substrate holder 1 is displaced by the first linear motor 147 a relatively small distance with respect to the movable portion 165 of the third linear motor 151.

The positioning device 21 of the substrate holder 1 is a kind similar to the positioning device 31 of the mask holder 5, and the fixing part of the second linear motor 149 of the first positioning device 21 ( The 153 is fixed to the force frame 41 of the lithographic apparatus, like the fixture 73 of the second linear motor 71 of the second positioning device 31, and during operation the first positioning device 21. The reaction force generated from the driving force applied by the substrate holder 1 on the substrate holder 1 by the first positioning device 21 is transmitted exclusively to the force frame 41. This is done so that the reaction force of the first positioning device 21 as well as the reaction force of the second positioning device 31 causes mechanical vibration to the force frame 41 and is not transmitted to the machine frame 45. Since the upper surface 141 of the granite support 143 on which the substrate holder 1 is guided extends perpendicular to the Z direction, the driving force of the first positioning device 21 also perpendicular to the Z direction. Itself does not cause any mechanical vibrations in the machine frame 45.

The pattern existing on the mask 29 is formed by the second positioning device 31 and the first positioning device 21, respectively, during the exposure of the semiconductor substrate 19 and the mask 29 and the semiconductor substrate 19. Since all of these are displaced with the above accuracy with respect to the focusing system 3 parallel to the X direction, and the mask 29 and the semiconductor substrate 19 are positioned parallel to the Y direction and the rotation axes 67,145 with the above accuracy. Are rotated with respect to each of them, so that they are projected onto the semiconductor substrate 19 with the above accuracy. The accuracy in which the pattern is projected onto the semiconductor substrate 19 is a positioning device because the mask holder 5 is not only displaced parallel to the X direction but also displaced parallel to the Y direction and rotatable about the rotation axis 67. Much better than the positioning accuracy of (21, 31). The displacement of the mask 29 relative to the focusing system 3 is actually dependent on the rate of displacement of the mask 29 and on the light reducing element of the focusing system 3. Equivalently, the pattern image on the semiconductor substrate 19 is changed. The pattern of the mask 29 is therefore projected onto the semiconductor substrate 19 with an accuracy comparable to the positioning accuracy percentage of the second positioning device 31 and the reducing factor of the focusing system 3.

7 and 8 show a cross section of one of the three dynamic insulators 51. The dynamic insulator 51 consists of a mounting plate 171 that is fixed to the corner 49 of the main plate of the machine frame 45 that depends on the dynamic insulator 51. The dynamic insulator 51 also includes a housing 173 fixed to the base 39 of the force frame 41. The mounting plate 171 is connected to the intermediate plate 177 suspended in the cylindrical tube 181 by three parallel tension rods 179 through a coupling rod 175 in a direction parallel to the Z direction. Only one tension rod 179 is visible in FIG. 7, and all three tension rods 179 are visible in FIG. The cylindrical tube 181 is positioned concentrically in the cylindrical chamber 183 of the housing 173. The space 185 existing between the cylinder tube 181 and the cylindrical chamber 183 forms part of the air spring 187, and the compressed air is filled through the moving valve. The space 185 is annular fixed between the first portion 193 and the second portion 195 of the cylindrical tube 181 and to the first portion 197 and the second portion 199 of the housing 173, Sealed by a flexible rubber membrane 191. The components of the lithographic apparatus supported by the machine frame 45 and the machine frame 45 are therefore supported in a direction parallel to the Z direction by compressed air in the space 185 of the three dynamic insulators 51, The cylindrical tube 181 and thus the machine frame 45 have any freedom of movement with respect to the cylindrical chamber 183 as a result of the flexibility of the membrane 191. The air spring 187 is rigid so that the mass spring system formed by the air spring 187 of the three dynamic insulators 51 and the components of the lithographic apparatus supported by the machine frame 45 and the machine frame 45 are relatively Have a small resonant frequency, for example, 3 Hz. The machine frame 45 is dynamically insulated from the force frame 41 with respect to mechanical vibrations having a frequency above a predetermined threshold, for example 10 Hz, as described above. As shown in FIG. 7, the space 185 couples to the side chamber 203 of the air spring 187 through a narrow passageway 201. Narrow passage 201 acts as a damper to brake the periodic movement of cylinder tube 181 relative to cylinder chamber 183.

As further shown in FIGS. 7 and 8, each dynamic insulator 51 includes a force actuator 205 that is integral with the dynamic insulator 51. The force actuator 205 includes an electrical coil holder 207 secured to the inner wall 209 of the housing 173. As shown in Fig. 7, the coil holder 207 includes an electric coil 211 extending perpendicular to the Z direction and indicated by broken lines in the drawing. The coil holder 207 is arranged between two magnetic yokes 213 and 215 fixed to the mounting plate 171. In addition, a pair of permanent magnets 217, 219, 221, 223 are fixed to each yoke 213, 215, and a pair of magnets 217, 219, 221, 223 are magnetized in opposite directions each time perpendicular to the plane of the electric coil 211. do. When current passes through the coil 211, the coil 211 and the magnets 217, 219, 221, 223 exert a Lorentz force parallel to the Z direction. The value of the Lorentz force is controlled by an electrical controller of a lithographic apparatus (not shown) as described in detail below.

The force actuator 205 integrally formed with the dynamic insulator 51 forms a force actuator system shown diagrammatically in FIG. 9 shows the machine frame 45, the substrate holder 1 and the mask holder 5 displaced relative to the machine frame 45, the base 39 and the three dynamic insulators 51 in a diagram. 9 is a mask holder with a gravity (Gs) center and a position of X (X _M) position of the Y (Y _M) of the substrate holder (1) having a position (Xs) and the Y position (Ys) of the X The reference point P of the machine frame 45 is further shown with respect to the center of gravity G _M of (5). The center of gravity Gs, G _M is the center of gravity of the total displacement mass of the substrate holder 1 with the semiconductor substrate 19 and the center of gravity of the total displacement mass of the mask holder 5 with the mask 29. To indicate. As shown in part in Figure 9, the Lorentz force of the three actuators 205, the force (F _{L.1, L.2} F, F _L.3) is the position of X of the reference point (P) (X _F.1 , X _F.2 , X _F.3 ) have an application point on the machine frame 45 with the positions of Y (Y _F.1 , Y _F.2 , Y _F.3 ). Since the machine frame 45 supports the substrate holder 1 and the mask holder 5 in parallel to the vertical Z direction, the mask holder 5 and the substrate holder 1 have support forces Fs and F _M , respectively. (1) and on the machine frame 45 having a value corresponding to the gravity value acting on the mask holder 5. The bearing forces Fs and F _M correspond to the positions of X and Y of the centers of gravity Gs and G _M of the substrate holder 1 and the mask holder 5, respectively. Has an application point relative to 45). When the substrate holder 1 and the mask holder 5 are displaced with respect to the machine frame 45 during the exposure of the semiconductor substrate 19, the support forces Fs and F _{M of the} substrate holder 1 and the mask holder 5 are changed. The point of application also displaces relative to the machine frame 45. The electrical controller of the lithographic apparatus includes a substrate for the Lorentz force is the sum of the mechanical moment of a reference point (F _{L.1, L.2} F, F _L.3) (P) for the reference point (P) of the machine frame 45 Lorentz force (F _L.1 , F _L.2 , F _L) to have the same value as the direction of the sum of the mechanical moments of the holding force (Fs, F _M ) of the holder (1) and the mask holder (5). and it controls the value of _0.3).

The controller for controlling the _{lens lens} force F _L.1 , F _L.2 , F _{L.3 includes} , for example, a feedforward control loop which is already known per se and is used in a performance, and the controller is a substrate holder ( From the position (Xs, Ys) of 1) and the electrical control unit (not shown) of the lithographic apparatus which controls the substrate holder 1 and the mask holder 5 to the position X _M , Y _M of the mask holder 5 And the received information relates to a desired position of the substrate holder 1 and the mask holder 5. The controller is optionally provided with a feedback control loop which is known per se and is performed in a performance manner, the information on the position Xs, Ys of the substrate holder 1 and the position X _M , Y _M of the mask holder 5. Information is received from the position control system of the lithographic apparatus, wherein the received information relates to the measurement position of the substrate holder 1 and the mask holder 5. The controller alternatively includes a combination of the feedforward and feedback control loops. Therefore, Lorentz force actuators of the force system _(L.1 F, F _{L.2, L.3} F) is a mask holder 5 and the substrate holder relating to the machine frame 45 by, and which forms a compensation force (1 The displacement of the center of gravity (Gs, G _M ) of) is compensated. The sum of the _bearing moments (Fs, F _M ) and Lorentz forces (F _L.1 , F _L.2 , F _L.3 ) with respect to the reference point (P) of the machine frame (45) is a constant value and direction. By having it, the substrate holder 1 and the mask holder 5 have a so-called virtual gravity center point having a substantially constant position with respect to the machine frame 45. Thus, the machine frame 45 does not detect the movement of the actual center point of the gravity Gs, G _M of the mask holder 5 and the substrate holder 1 during exposure of the semiconductor substrate 19. Without the force actuator system described above, the movement of the substrate holder 1 and the mask holder 5 results in an uncompensated change in the mechanical moment of the bearing forces Fs, F _M with respect to the reference point P, and as a result The machine frame 45 makes a low frequency vibrational motion on the elastic strain or mechanical vibration or dynamic insulator 51 that may occur therefrom.

The integration of three dynamic insulators 51 and three force actuators 205 results in a compact and simple structure of the force actuator system and the lithographic apparatus. In addition, the triangular arrangement of the dynamic insulators 51 makes the operation of the force actuator system particularly stable. Since the compensating force of the force actuator system exclusively includes Lorentz forces, mechanical vibrations occur on the base 39 and no force frame 41 is transmitted to the machine frame 45 through the force actuator 205.

Exclusive direct introduction of the reaction forces of the above-described means, namely the positioning devices 21, 31 into the force frame 41, by the Lorentz force exclusively by the substrate holder 1 with the force frame 41. The direct connection of the mask holder 5 and the compensating force of the force actuator 205 result in the machine frame 45 having only a supporting function. Practically no force that changes value and direction is seen on the machine frame 45. For example, a viscous horizontal frictional force is applied to the planar guide 65 of the support member 57 and the upper surface 141 of the granite support 143 during the movement of the substrate holder 1 and the mask holder 5. Exceptions can occur, such as those caused by the aerodynamic bearings of the substrate holder 1 and the mask holder 5 in the present invention. However, since the frictional force is relatively small, it does not cause great vibration or deformation in the machine frame 45. Since the machine frame 45 does not cause mechanical vibration or elastic deformation, the components of the lithographic apparatus supported by the machine frame 45 are accurately positioned in a defined position with respect to each other. In particular, the position of the substrate holder 1 in relation to the focusing system 3 and the position of the mask holder 5 in relation to the focusing system 3 are very precisely defined, and the substrate holder 1 and the mask holder 5 are also very precisely defined. Can be positioned very accurately in relation to the focusing system 3 by the positioning devices 21, 31, so that the pattern of the semiconductor circuit present on the mask can be projected onto the semiconductor substrate with an accuracy in the sub-micron range. It means that there is. Moreover, since the machine frame 45 and the focusing system 3 are not subjected to mechanical vibrations or elastic deformations, the machine frame 45 may, for example, recall the position sensor of a position control system such as an optical element and a laser interferometer system. There is an advantage that it can serve as a reference frame for the position control system of the substrate holder 1 and the mask holder 5 directly mounted to the machine frame 45. The direct mounting of the position sensor to the machine frame 45 means that the position occupied by the position sensor in relation to the substrate holder 1, the focusing system 3 and the mask holder 5 is not affected by mechanical vibration or deformation. A reliable and accurate measurement of the position of the substrate holder 1 and the mask holder 5 relative to the focusing system 3 can be made. Since the mask holder 5 can not only be located parallel to the X direction, but also can be located parallel to the Y direction and rotated about the axis of rotation 67, by the lithographic apparatus according to the invention as described above. It has high precision in forming the pattern of the mask 29 on the semiconductor substrate 19 having a small dimension in the sub-micron range which can be manufactured.

The lithographic apparatus according to the invention is moved by a substrate holder 1 movable by the first positioning apparatus 21 according to the invention and a second positioning apparatus 31 according to the invention as described above. A possible mask holder 5 is provided. The positioning devices 21, 31 comprise a common first frame, ie a mechanical frame 45 of the lithographic apparatus and a common second frame, ie a force frame 41 of the lithographic apparatus. The positioning devices 21, 31 each have their own first and second frames, each with a common first frame and their own second frame or with the same second frame and their own first frame, respectively. .

The invention further illustrates that the lithographic apparatus uses the "step and repeat" principle if described above. For example, the positioning device according to the invention is used in the movement of a substrate holder of a lithographic apparatus which is disclosed in EP-A-0 498 496 and in which the substrate holder exclusively travels a relatively large distance with respect to the focusing system. The lithographic apparatus according to the present invention also provides a conventional mask holder in which the second positioning device 31 with the mask holder 5 is stopped in relation to the machine frame 45 as disclosed in EP-A-0 498 496. In the lithographic apparatus as shown in the figure. The present invention also provides a lithographic apparatus that is driven by a conventional " step and scan " principle, i.e. a mask holder driven only by the positioning device according to the invention and a conventional positioning device as disclosed in EP-A-0 498 496. It is driven by the substrate holder. The above is that if the focusing system of the lithographic apparatus has a relatively large optical reduction factor, the movement of the substrate holder is relatively small with respect to the movement of the mask holder, and the positioning device of the substrate holder causes relatively little mechanical vibration in the machine frame. It is.

The lithographic apparatus described above is common to the first positioning device 21 and the second positioning device 31, and a compensation in which gravity center movement of both the substrate holder 1 and the mask holder 5 can be compensated for. And a force actuator system for supplying force. The lithographic apparatus according to the invention is provided with two force actuator systems in which the movement of the center of gravity of the substrate holder 1 and the mask holder 5 is individually corrected. The lithographic apparatus according to the invention also comprises a single force actuator system in which the movement of the center of gravity of the mask holder 5 can be exclusively corrected. The above is that if the focusing system of the lithographic apparatus has a relatively large optical reduction factor, the movement of the center of gravity of the substrate holder is relatively small with respect to the movement of the center of gravity of the mask holder, and the movement of the center of gravity of the substrate holder is a machine frame. Will cause relatively little mechanical vibration.

As described above, the lithographic apparatus according to the invention is used to expose a semiconductor substrate in the manufacture of integrated electronic semiconductor circuits. The lithographic apparatus is also used as an alternative to the manufacture of other products having small dimensional structures in the submicron range that form mask patterns on substrates by the apparatus. The concept is connected to the structure of the liquid crystal display pattern as well as the structure of the conduction and detection pattern of the magnetic domain memory or the integrated optical system.

In addition, the positioning device according to the invention can be used not only in a lithographic apparatus but also in other apparatuses in which a particular object or substrate is positioned in a precise manner. For example, it can be used in an apparatus for analyzing and measuring an object or material that is precisely positioned and moved in relation to a measuring system and a scanning system. The positioning device according to the present invention is also applied to a precision machine tool using a material that is precisely processed in the submicron range, such as a lens. The positioning device according to the present invention is also used for positioning a workpiece in relation to a rotating tool, and for positioning a tool in relation to a rotating workpiece.

The first positioning device 21 of the lithographic apparatus described above comprises a drive unit equipped with a first linear motor and a conventional second and third linear motor for exclusively supplying Lorentz forces, The second positioning device 31 comprises a drive unit equipped with a first linear motor and a single conventional second linear motor for exclusively supplying the Lorentz force. The invention also relates to a positioning device equipped with another drive unit. As an example, the magnet system of the motor is fixed to an object table supported by the first frame, the electric coil system of the motor is fixed to the second frame, and includes a single said motor exclusively supplying Lorentz force. There is a positioning device and a positioning device including a single conventional motor, in which a fixed part of the motor is fixed to the second frame, and a movable part of the motor is fixed to an object table supported by the first frame.

Claims (22)

A positioning device having an object table and a drive unit, wherein the positioning device is displaceable by the drive unit onto a guide in which the object table is parallel to the X direction, the guide being a first frame of the positioning device. Fixed to the second frame of the positioning device which is dynamically insulated from the first frame, And a reaction force exerted by the object table on the drive unit in operation and generated from the driving force exerted by the drive unit on the object table is transferred exclusively to the second frame. The method of claim 1, And the object table is exclusively coupled to the fixed portion of the drive unit by the Lorentz force of the electric coil system and the magnet system of the drive unit during operation. The method of claim 2, The magnet system and the electric coil system belong to the first linear motor of the drive unit, and the drive unit includes a fixed part fixed to the second frame and a movable part which is displaceable parallel to the X direction over the guide of the fixed part. And a second linear motor, a magnet system of the first linear motor fixed to the object table, and an electric coil system of the first linear motor fixed to the movable part of the second linear motor. The method of claim 3, The drive unit includes a third linear motor having a fixed part fixed to the movable part of the second linear motor and a movable part displaceable in parallel to the Y direction perpendicular to the X direction over the guide of the fixed part of the third linear motor, And an electric coil system of the first linear motor fixed to the movable part of the three linear motor. The method of claim 1, The positioning device is provided with a force actuator system that applies a compensating force on a first frame during operation and is controlled by an electrical control unit, the compensating force being the value of the mechanical moment of gravity acting on the object table with respect to a reference point. And a direction opposite to the direction of the mechanical moment with respect to the reference point of the first frame having a value corresponding to the direction of the mechanical moment of gravity. The method of claim 5, And the object table is displaceable parallel to the horizontal direction, while the force actuator system exerts a compensating force on the first frame parallel to the vertical direction. The method of claim 6, The object table is displaceable parallel to the horizontal X direction and parallel to the horizontal Y direction perpendicular to the X direction, while the force actuator system comprises three force actuators arranged in triangles with each other, each parallel to the vertical direction. Positioning device, characterized in that for applying a compensation force on the first frame. The method of claim 5, And the force actuator system is integrated with a system of dynamic insulators whereby the first frame is coupled to the base of the positioning device. The method of claim 5, And said compensating force exclusively comprises the Lorentz force of the electric coil system and the magnet system of said force actuator system. A lithographic apparatus having a machine frame that supports a substrate holder displaceable perpendicularly to the Z direction by a positioning device and a focusing system having a main axis directed in parallel to the vertical Z direction and in turn parallel to the Z direction. In The positioning device of the substrate holder includes an object table and a driving unit, by which the object table is displaceable onto the guide parallel to the X direction, the guide being fixed to the first frame of the positioning device. On the other hand, the fixing portion of the drive unit is fixed to the second frame of the positioning device that is dynamically insulated from the first frame, the first frame of the positioning device of the substrate holder belongs to the mechanical frame of the lithographic apparatus, The second frame of the positioning device of the substrate holder belongs to the force frame of the lithographic apparatus which is dynamically insulated from the machine frame, and in operation is driven from the driving force applied by the object table on the drive unit and applied by the drive unit on the object table. Generated reaction force can be transferred exclusively to the second frame. Lithographic apparatus, characterized in that. Displacement perpendicular to the Z direction by a further positioning device, parallel to the Z direction, in turn a radiation source, a mask holder displaceable perpendicularly to the Z direction by the positioning device, a focusing system having a principal axis directed parallel to the Z direction and A lithographic apparatus having a machine frame that supports a possible substrate holder, The positioning device of the mask holder includes an object table and a driving unit, by which the object table is displaceable onto the guide parallel to the X direction, the guide being fixed to the first frame of the positioning device. On the other hand, the fixing part of the driving unit is fixed to the second frame of the positioning device which is dynamically insulated from the first frame, and the first frame of the positioning device of the mask holder belongs to the machine frame of the lithographic apparatus, The second frame of the positioning device of the mask holder belongs to the force frame of the lithographic apparatus which is dynamically insulated from the machine frame, and in operation is driven from the driving force exerted by the object table on the drive unit and applied by the drive unit on the object table. Generated reaction force is exclusive to the second frame. Lithographic apparatus, which can be delivered to. The method of claim 10, The mask holder is displaceable perpendicularly to the Z direction by the positioning device, wherein the first frame of the positioning device of the mask holder belongs to the machine frame of the lithographic apparatus, while the first of the positioning device of the mask holder A lithographic apparatus according to claim 2, wherein the two frames belong to a force frame of the lithographic apparatus. The method of claim 11, The positioning device of the substrate holder and the mask holder has a joint force actuator system which applies a compensating force on the machine frame of the lithographic apparatus during operation and is controlled by the electrical control unit, the compensating force being the substrate holder with respect to the reference point. The mechanical moment relative to the reference point of the mechanical frame at a value coinciding with the sum of the mechanical moments of gravity acting on the phase, and the mechanical moment of gravity acting on the mask holder relative to the reference point and the direction of the sum of the mechanical moments relative to the reference point. Lithographic apparatus characterized by having a direction. The method of claim 13, The machine frame is arranged on the base of the lithographic apparatus, on which the force frame is arranged by three dynamic insulators arranged in a triangle, respectively, while the joint force actuator system is each integrated with a corresponding one dynamic insulator. A lithographic apparatus comprising three separate force actuators. The method of claim 2, The positioning device is provided with a force actuator system which exerts a compensating force on the first frame during operation and is controlled by an electrical control unit, the compensating force of the mechanical moment of gravity acting on the object table with respect to the reference point. And a direction opposite to the direction of the mechanical moment relative to the reference moment of the first frame having a value coinciding with the value and the mechanical moment of gravity. The method of claim 3, The positioning device is provided with a force actuator system which exerts a compensating force on the first frame during operation and is controlled by an electrical control unit, the compensating force of the mechanical moment of gravity acting on the object table with respect to the reference point. And a direction opposite to the direction of the mechanical moment relative to the reference moment of the first frame having a value coinciding with the value and the mechanical moment of gravity. The method of claim 4, wherein The positioning device is provided with a force actuator system which exerts a compensating force on the first frame during operation and is controlled by an electrical control unit, the compensating force of the mechanical moment of gravity acting on the object table with respect to the reference point. And a direction opposite to the direction of the mechanical moment relative to the reference moment of the first frame having a value coinciding with the value and the mechanical moment of gravity. The method of claim 6, The force actuator system is integral with the system of dynamic insulator, whereby the first frame is coupled to the base of the positioning device. The method of claim 7, wherein The force actuator system is integral with the system of dynamic insulator, whereby the first frame is coupled to the base of the positioning device. The method of claim 6, And said compensating force exclusively comprises Lorentz forces of an electric coil system and a magnet system of said force actuator system. The method of claim 7, wherein And said compensating force exclusively comprises Lorentz forces of an electric coil system and a magnet system of said force actuator system. The method of claim 8, And said compensating force exclusively comprises Lorentz forces of an electric coil system and a magnet system of said force actuator system.