Exposure apparatuses for semiconductor processing are commonly used to transfer images from a reticle onto a semiconductor wafer. A typical exposure apparatus includes an illumination source, a reticle stage assembly that retains a reticle, a lens assembly and a wafer stage assembly that retains a semiconductor wafer. The images transferred onto the wafer from the reticle are extremely small. Accordingly, the precise positioning of the wafer and the reticle is critical to the manufacturing of the wafer. In order to obtain precise relative alignment, the position of the reticle and the wafer are constantly monitored by a measurement system.
Typically, the reticle stage assembly including one or more movers that move and position the reticle, and the wafer stage assembly includes one or more movers that move and position the wafer. Unfortunately, electrical current directed to the movers generates heat that is subsequently transferred to the surrounding environment, including the air surrounding the movers and the other components positioned near the movers. The heat changes the index of refraction of the surrounding air. This reduces the accuracy of the measurement system and degrades machine positioning accuracy. Further, the heat causes expansion of the other components of the machine. This further degrades the accuracy of the machine.
Conventionally, the movers are cooled by forcing a coolant around the movers. However, existing coolant systems do not efficiently cool the movers and as a result allow for heat to be transferred from the movers to the surrounding environment. This reduces the accuracy of positioning of the wafer relative to the reticle, and degrades the accuracy of the exposure apparatus.
The present invention is directed to stage assembly that moves a device along a first axis. The stage assembly can include a stage that retains the device, a base assembly, a stage mover that moves the stage, and a temperature adjuster that adjusts the temperature of at least a portion of the stage mover. The stage mover includes a magnet array that is secured to one of the stage and the base assembly, and a conductor array that is secured to the other of the stage and the base assembly. As provided herein, current directed to the conductor array creates a force that can be used to move one of the arrays relative to the other array.
The temperature adjuster includes a first plate, a first thermal insulator, a circulation housing, a first fluid system, and a second fluid system. The first plate is positioned adjacent to a first side of the conductor array, the first plate defining a first plate channel. The first thermal insulator is positioned adjacent to the first plate. The circulation housing defines at least a portion of a housing passageway that is positioned adjacent to the first thermal insulator. The first fluid system directs a first circulation fluid through the housing passageway, the second fluid system directs a second circulation fluid through the first plate channel. With this design, the second circulation fluid removes the majority of the heat from the conductor array, and the first circulation fluid shields an outer surface of the circulation housing from thermal disturbance.
In one embodiment, the circulation housing encircles the first plate, the first thermal insulator, and at least a portion of the conductor array. Further, the temperature adjuster can include (i) a second plate positioned adjacent to a second side of the conductor array, the second plate defining a second plate channel, and (ii) a second thermal insulator positioned adjacent to the second plate; wherein the second fluid system directs the second circulation fluid through the second plate channel.
In another embodiment, the conductor array can include a first conductor unit and a second conductor unit, and the temperature adjuster can include a separate first plate and a separate first thermal insulator for the first conductor unit and the second conductor unit. Further, the circulation housing can include a separate surface housing for the first conductor unit and the second conductor unit.
As provided herein, the problem of removing heat from stage mover without creating unacceptable thermal disturbances is solved by using high-pressure cold-plate cooling and a high temperature rise to remove the majority of the heat from the coils, and surrounding the exterior of the cold-plates with a low pressure conventional cooling jacket to shield the exterior of the stage mover from thermal disturbances caused by the large temperature rise.
The present invention is also directed to an exposure apparatus, a device manufactured with the exposure apparatus, and/or a wafer on which an image has been formed by the exposure apparatus. Further, the present invention is also directed to a method for making a stage assembly, a method for making an exposure apparatus, a method for making a device and a method for manufacturing a wafer.
The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:
Referring initially to
As an overview, in certain embodiments, the stage mover 16 and the temperature adjuster 20 are uniquely designed and controlled to efficiently maintain a substantially uniform temperature of a portion of the temperature adjuster 20 and/or the base assembly 18. This can reduce the amount of heat transferred from the stage mover 16 to the surrounding environment. With this design, the stage mover 16 can be placed closer a measurement system (not shown in
The stage assembly 10 is particularly useful for precisely positioning a device 26 during a manufacturing and/or an inspection process. The type of device 26 positioned and moved by the stage assembly 10 can be varied. For example, the device 26 can be a semiconductor wafer, and the stage assembly 10 can be used as part of an exposure apparatus 930 (illustrated in
Some of the Figures provided herein include an orientation system that designates an X axis, a Y axis, and a Z axis. It should be understood that the orientation system is merely for reference and can be varied. For example, the X axis can be switched with the Y axis and/or the stage assembly 10 can be rotated. Moreover, these axes can alternatively be referred to as a first, second, or third axis.
The stage base 12 supports a portion of the stage assembly 10 above the mounting base 924. In the embodiment illustrated herein, the stage base 12 is rigid and is generally rectangular plate shaped, although other shapes and configurations of the stage base 12 are possible.
The stage 14 retains the device 26. The stage 14 is precisely moved by the stage mover 16 to precisely position the device 26. In one embodiment, the stage 14 is generally rectangular shaped and includes a device holder (not shown) for retaining the device 26. The device holder can be a vacuum chuck, an electrostatic chuck, or some other type of clamp. In the embodiments illustrated herein, the stage assembly 10 includes a single stage 14 that is moved relative to the stage base 12. Alternatively, for example, the stage assembly 10 can be designed to include multiple stages that are independently moved relative to the stage base 12.
The stage mover 16 controls and adjusts the position of the stage 14 and the device 26 relative to the base assembly 18 and the stage base 12. For example, the stage mover 16 can be a planar motor that moves and positions of the stage 14 with six degrees of freedom (e.g. along the X, Y, and Z axes, and about the X, Y, and Z axes). Alternatively, the stage mover 16 can be designed to move the stage 14 with fewer than six degrees of freedom. For example, the stage 14 can be maintained along the Z axis with a vacuum preload type fluid bearing or another type of bearing and the stage mover 16 can move the stage 14 with three degrees of freedom (e.g. along the X axis, along the Y axis, and about the Z axis).
In one embodiment, the stage mover 16 is an electromagnetic actuator that includes a conductor array 36 (illustrated in phantom) and a magnet array 38 (illustrated as a box). One of the arrays 36, 38 is secured to the top of the base assembly 18 and the other array 36, 38 is secured to the bottom of the stage 14. In
In
The magnet array 38 includes a plurality of magnets. The size, shape and number of magnets can be varied to suit the design requirements of the stage mover 16. Each magnet can be made of a permanent magnetic material such as NdFeB.
Electrical current (not shown) is independently supplied to the conductor units 40 by the control system 22. The electrical current in the conductor units 40 interact with the magnetic field(s) of the one or more magnets in the magnet array 38. This causes a force (Lorentz type force) between the conductor units 40 and the magnets that can be used to move the stage 14 relative to the stage base 12.
Unfortunately, the electrical current supplied to the conductor array 36 also generates heat, due to resistance in the conductor array 36. Moreover, the resistance of the conductor array 36 increases as temperature increases. This exacerbates the heating problem and reduces the performance and life of the stage mover 16. Heat transferred to the base assembly 18 can cause expansion and distortion. Further, heat transferred to the surrounding environment can adversely influence the measurement system. In certain embodiments, the temperature adjuster 20 provided herein efficiently removes the heat and inhibits the transfer of the heat to the base assembly 18 and the surrounding environment.
The base assembly 18 can be any structure, and in certain embodiments, the base assembly 18 receives the reaction forces generated by the stage mover 16. In certain embodiments, the base assembly 18 is a reaction assembly that counteracts, reduces and minimizes the influence of the reaction forces from the stage mover 16 on the position of the stage base 12. Further, this allows for more accurate positioning of the stage 14. As provided above, the conductor array 36 of the stage mover 16 is coupled to the base assembly 18. With this design, the reaction forces generated by the stage mover 16 are transferred to the base assembly 18. When the stage mover 16 applies a force to move the stage 14, an equal and opposite reaction force is applied to the base assembly 18. In
With this design, (i) movement of the stage 14 with the stage mover 16 along the X axis, generates an equal and opposite X reaction force that moves the countermass base assembly 18 in the opposite direction along the X axis; (ii) movement of the stage 14 with the stage mover 16 along the Y axis, generates an equal and opposite Y reaction force that moves the countermass reaction assembly 18 in the opposite direction along the Y axis; and (iii) movement of the stage 14 with the stage mover 16 about the Z axis generates an equal and opposite theta Z reaction moment (torque) that moves the countermass base assembly 18 about the Z axis.
In certain embodiments, the ratio of the mass of the countermass reaction assembly 18 to the mass of the stage 14 is relatively high. This will minimize the movement of the countermass base assembly 18 and minimize the required travel of the countermass base assembly 18. A suitable ratio of the mass of the countermass base assembly 18 to the mass of the stage 14 is between approximately 2:1 and 10:1. In one embodiment, the countermass base assembly 18 comprises components made from a non-electrically conductive, non-magnetic material, such as low electrical conductivity stainless steel or titanium, or non-electrically conductive plastic or ceramic.
The temperature adjuster 20 can be used to reduce the influence of the heat from the conductor array 36 from adversely influencing the other components of the stage assembly 10. The design of the temperature adjuster 20 can vary. In one embodiment, the temperature adjuster 20 includes (i) a first fluid system 42A (illustrated as a box), (ii) a second fluid system 44A (illustrated as a box), (iii) a circulation housing 46, (iv) a plate assembly 248 (illustrated in
Further, as provided herein, (i) the first fluid system 42A directs a first circulation fluid 42B (illustrated as small triangles) into the circulation housing 46 to maintain the temperature of an outer surface 46A of the circulation housing 46 at a predetermined temperature, (ii) the second fluid system 44A directs a second circulation fluid 44B (illustrated as small squares) through the plate assembly 248 to remove the bulk of the heat created by the conductor units 40, and (iii) the insulation assembly 250 reduces the amount of heat transferred from the plate assembly 248 to the first circulation fluid 42B. With this design, the temperature of the outer surface 46A of the circulation housing 46 is easier to maintain at the predetermined temperature.
Each fluid system 42A, 44A can include one or more pumps, reservoirs, heat exchanges, chillers, pressure controllers, manifolds, and/or valves.
Further, the type of circulation fluid 42B, 44B can be varied. For example, each circulation fluid 42B, 44B can be water. In another embodiment, the composition of the circulation fluids 42B, 44B can be different. For example, the specific heat of the first circulation fluid 42B can be different from that of the second circulation fluid 44B. In alternative embodiments, the specific heat of the first circulation fluid 42B can be greater or smaller than the specific heat of the second circulation fluid 44B. Additionally, the thermal conductivity of the first circulation fluid 42B can be greater or smaller than the thermal conductivity of the second circulation fluid 44B. As an example, the first circulation fluid 42B can be Fluorinert and the second circulation fluid 44B can be water. In this example embodiment, the high specific heat of water allows the second circulation fluid 44B to remove a larger amount of heat for a corresponding change in the fluid temperature. The low thermal conductivity of Fluorinert reduces the heat transfer through the first circulation fluid 42B to the circulation housing 46.
In certain embodiments, the circulation fluid 42B, 44B can be referred to as a coolant.
The control system 22 is electrically connected to, directs and controls electrical current to the conductor array 36 of the stage mover 16 to precisely position the device 26. Further, the control system 22 is electrically connected to and controls (i) the first circulation system 42A to control the temperature, flow rate and pressure of the first circulation fluid 42B directed into the circulation housing 46, (ii) the second circulation system 44A to control the temperature, flow rate and pressure of the second circulation fluid 44B directed into the plate assembly 248. This allows the control system 22 to accurately control the temperature of the circulation housing 46. The control system 22 can include one or more processors and circuits.
Alternatively, in certain embodiments, the temperature adjuster 20 can be designed without the upper plate(s) 248A, the lower plate(s) 248B, the upper insulator(s) 250A, and/or the lower insulator(s) 250B.
In
In
In this embodiment, for each conductor unit 40, the assembly includes (i) a first inlet tube 258A that connects the first plate inlet 254A in fluid communication with the second fluid system 44A, (ii) a second inlet tube 258B that connects the second plate inlet 254B in fluid communication with the second fluid system 44A, (iii) a first outlet tube 260A that connects the first plate outlet 256A in fluid communication with the second fluid system 44A, and (iv) a second outlet tube 260B that connects the second plate outlet 256B in fluid communication with the second fluid system 44A.
In one embodiment, each plate 248A, 248B is rigid and rectangular plate shaped. Further, in this embodiment, each plate channel 252A, 252B is a micro-channel (e.g. a very small channel). With this design, the second fluid system 44A can direct the second circulation fluid 44B into the plates 248A, 248B are at high pressure and a high flow rate without distorting the plates 248A, 248B. This feature allows the second fluid system 44A to remove the bulk of the heat from the conductor units 40. As non-exclusive examples, the pressure in each plate channel 252A, 252B can be between approximately ten psi and fifteen psi, and/or the flow rate in each plate channel 252A, 252B can be between approximately thirty psi and fifty psi.
Further, because, the insulation assembly 250 inhibits the transfer of heat from the plate assembly 248 to the first circulation fluid 42B, the temperature of the plate assembly 248 can be very different from the temperature of the first circulation fluid 42B without adversely influencing the temperature of the outer surface 46A. As a result thereof, the second circulation fluid 44B traveling through the plate assembly 248 can experience a relatively large temperature increase (delta T) without adversely influencing the temperature of the outer surface 46A. As a non-exclusive example, the change in temperature from the plate inlet 254A, 254B to the plate outlet 256A, 256B for one or more of the plates 248A, 248B can be between five and fifteen degrees. With this design, the plates 248A, 248B are very efficient in removing heat, particularly if a large delta T is used.
In one embodiment, the circulation housing 46 defines (i) the outer surface 46A that faces the magnet array 38 (illustrated in
In one embodiment, the circulation housing 46 can be made of a rigid, non-electrically conductive, non-magnetic material, such as titanium, or non-electrically conductive plastic or ceramic.
Further, in
With the present design, the first circulation fluid 42B flowing in the circulation housing 46 removes very little heat and provides a thermal shield for outer surface 46. With this design, the first fluid system 42A can direct the first circulation fluid 42B into the housing passageway 246B at relatively low pressure and a relatively low high flow rate. As a result thereof, the circulation housing 46 is easier to support and bulging is minimized. As non-exclusive examples, the pressure in the circulation housing 46 can be between approximately three psi and five psi, and/or the flow rate in the circulation housing 46 can be between approximately five liters/minute and twenty liters/minute.
Further, with this design, because the first circulation fluid 42B removes very little heat, the first circulation fluid 42B traveling through the circulation housing 46 will experience very little temperature increase (delta T). With this design, the temperature of the first circulation fluid 42B at the housing inlet 246C can be controlled to be approximately equal to the predetermined desired temperature. As a non-exclusive example, the change in temperature of the first circulation fluid 42B from the housing inlet 246C to the housing outlet 246D can be less than approximately one degree. With this small delta T, there is only a very minimal thermal gradient on the outer surface 46A, and very minimal thermal distortion.
As non-exclusive examples, (i) the pressure of the first circulation fluid 42B at the housing inlet 246C can be approximately 10, 20, 30, or 50 percent less than the pressure of the second circulation fluid 44B at the plate inlets 254A, 254B; (ii) the flow rate of the first circulation fluid 42B can be approximately 10, 20, 30, or 50 percent less than the flow rate of the second circulation fluid 44B; (iii) the delta T of the first circulation fluid 42B can be approximately 50, 70, 90, or 99 percent less than the delta T of the second circulation fluid 44B; and/or (iv) the temperature of the first circulation fluid 42B at the housing inlet 246C can be approximately 0, 1, 5, or 10 degrees more than the temperature of the second circulation fluid 44B at the plate inlets 254A, 254B.
In one, non-exclusive embodiment, the temperature of the first circulation fluid 42B at the housing inlet 246C is approximately equal to a room temperature of the room in which the mover combination 326 is located and the temperature of the second circulation fluid 44B at the plate inlets 254A, 254B is at least approximately ten degrees Celsius less.
As provided herein, the problem of removing heat from the conductor units 40 without creating unacceptable thermal disturbances is solved by using high-pressure cold-plate 248A, 248B cooling and a high temperature rise to remove the majority of the heat from the conductor units 40; and surrounding the exterior of the cold-plates 248A, 248B with a low pressure cooling jacket 46 to shield the exterior 46A of the motor from thermal disturbances caused by the large temperature rise.
As provided herein, in one embodiment, the second fluid system 44A can direct the second circulation fluid 44B into each plate 248A, 248B of each conductor unit 240A, 240B, 240C at approximately the same pressure and approximately at the same temperature. Alternatively, the second fluid system 44A can be designed to direct the second circulation fluid 44B into each plate 248A, 248B of each conductor unit 240A, 240B, 240C at a different pressure and/or different temperature. With this design, the second fluid system 44A can be controlled by the control system 22 (illustrated in
Stated in another fashion, the flow rate and/or temperature of the second circulation fluid 44B can be individually adjusted (as needed based on the power consumption) to remove the majority of the heat from each conductor units 240A, 240B, 240C. Further, the first circulation fluid 42B can be used as a thermal shield to maintain the outer surface 46A to inhibit the transfer of heat from each conductor unit 240A, 240B, 240C.
Additionally, in one embodiment, each conductor unit 240A, 240B, 240C can include one or more feedback elements 264 (represented with an “x” in
In this non-exclusive embodiment, the first conductor unit 240A includes a single, first coil set 262A, and the second conductor unit 240B includes a single, second coil set 262B. The design of each coil set 262A, 262B can be varied to suit the design requirements of the stage mover. For example, each coil set 262A, 262B can include one or more conductors 262C. For a three phase linear or planar motor, each coil set 262A, 262B preferably includes three adjacent racetrack shaped conductors 262C (e.g. coils). In one embodiment, (i) the first coil set 262A can also be referred to as a Y coil set because current directed to the first coil set 262A is used to generate a force along the Y axis; and (ii) the second coil set 262B can be referred to as an X coil set because current directed to the second coil set 262B is used to generate a force along the X axis. Each conductor 262C can be made of metal such as copper or any substance or material responsive to electrical current and capable of creating a magnetic field. Each conductor 262C can be made of wire encapsulated in an epoxy or another insulating polymer.
In this embodiment, each plate 248A, 248B is a rigid, generally rectangular plate shaped, and is sized to approximately cover the respective conductor unit 240A, 240B. Alternatively, each plate 248A, 248B can be sized and shaped to cover only a portion of the conductor unit 240A, 240B, or each plate 248A, 248B can be sized and shaped to cover multiple conductor units 240A, 240B. As a non-exclusive example, each plate 248A, 248B can have a thickness of approximately six hundred microns. Stated in another fashion, each plate 248A, 248B can have thickness of between approximately 300 and 1500 microns. Non-exclusive examples of suitable materials for the plates 248A, 248B include copper, titanium, stainless-steel or other materials with thermal, electrical, magnetic, and mechanical properties suitable for a particular application.
As provided above, each plate 248A, 248B includes the micro channel 252A, 252B (illustrated in phantom) that weaves back and forth within the respective plate 248A, 248B. For example, each plate 248A, 248B can be made by welding two half plates together. In this example, for each plate 248A, 248B, each half plate can include a portion of the channel etched into the half plate. Subsequently, for each plate 248A, 248B, the half plates can be assembled to create the micro channels 252A, 252B. As a non-exclusive embodiment, each micro channel 252A, 252B can have cross-section dimensions (perpendicular to the fluid flow) of approximately a few microns wide up to a few hundreds of microns in the Z direction and between one and twenty millimeters in the XY plane. Stated in another fashion, each micro channel 252A, 252B can have a cross-section area (perpendicular to the direction of fluid flow) of between approximately 0.01 and 5 square millimeters. Stated in yet another fashion, each micro channel 252A, 252B can have a cross-section area of less than approximately 0.01, 0.05, 0.1, 0.5, 1, 2, 3, 4, or 5 square millimeters
Further, in this embodiment, each thermal insulator 250A, 250B is generally rectangular plate shaped and is sized to approximately cover the respective plate 248A, 248B. Alternatively, each insulator 250A, 250B can be sized and shaped to cover only a portion of the respective plate 248A, 248B, or each insulator 250A, 250B can be sized and shaped to cover multiple plates 248A, 248B, or each insulator 250A, 250B can be larger than the respective plate 248A, 248B. Each thermal insulator 250A, 250B can be made of a material that is a good thermal insulator (has low coefficient of thermal transfer). With this design, the insulator 250A, 250B inhibits hot or cold portions of the plates 248A, 248B from adversely influencing the temperature of the first circulation fluid 42B and the temperature of the outer surface 46A. As a non-exclusive example, each plate insulator 250A, 250B can have thickness of between approximately one and one thousand microns. Suitable materials for the thermal insulators 250A, 250B include materials having a relatively low coefficient of heat transfer. As a non-exclusive example, the thermal insulators 250A, 250B can have a coefficient of heat transfer of less than approximately one Watt/meter-Kelvin. Non-exclusive examples of suitable materials for the thermal insulators 250A, 250B include plastic, carbon fiber or fiberglass composite, or a closed-cell foam material such as aerogel.
Moving from the bottom to the top in
In
In
With this design, the second fluid system 344A directs the second circulation fluid 344B through the plates 348A, 348B, 348C to remove the bulk of the heat from the assembly.
In this non-exclusive embodiment, each coil set 362A, 362B can also be referred to as a Y coil set because current directed to each coil set 362B is used to generate a force along the Y axis. Depending on the requirements of a particular application, other conductor units such as 340B, 340C could be configured as X coil sets by rotating the corresponding coil sets by 90° about the Z axis. Alternatively, for example, one or both of the coil sets 362A, 362B can be rotated ninety degrees and can be used to generate a force along the X axis.
Moving from the bottom to the top in
In this non-exclusive embodiment, (i) the first coil set 462A is an X coil set because current directed to the first coil set 462A is used to generate a force along the X axis; (ii) the second coil set 462B is a Y coil set because current directed to the second coil set 462B is used to generate a force along the Y. Alternatively, the orientations of the coil sets 462A, 462B can be reversed.
Moving from the bottom to the top in
In
For example, each conductor unit 540A, 540B, 540C can include a single coil set, or multiple coil sets (as illustrated in
More specifically, in the embodiment, the temperature adjuster 620 includes (i) a first fluid system 642A (illustrated as a box), (ii) a second fluid system 644A (illustrated as a box), (iii) a plate assembly 648 (illustrated in FIG. 6B), and (iv) an insulation assembly 650 (illustrated in
Alternatively, the surface housing 647 can sized to be positioned over multiple conductor units 640.
Further, in
As provided herein, the problem of removing heat from conductor array 836 without creating unacceptable thermal disturbances is solved by using high-pressure cold-plates 848A, 848B cooling and a high temperature rise to remove the majority of the heat from the conductor array 836, and surrounding the exterior of the cold-plates 848A, 848B with a low pressure circulation housing 846 (cooling jacket) to shield the exterior of the conductor array 836 from thermal disturbance caused by the large temperature rise.
In certain embodiments, the plate fluid removes the heat while the circulation fluid maintains the surface temperature.
It should also be noted that the present invention can be used in other types of actuators, such as a voice coil motor.
The exposure apparatus 930 is particularly useful as a lithographic device that transfers a pattern (not shown) of an integrated circuit from the reticle 988 onto the semiconductor wafer 990. The exposure apparatus 930 mounts to the mounting base 924, e.g., the ground, a base, or floor or some other supporting structure.
The apparatus frame 980 is rigid and supports the components of the exposure apparatus 930. The design of the apparatus frame 980 can be varied to suit the design requirements for the rest of the exposure apparatus 930.
The illumination system 982 includes an illumination source 992 and an illumination optical assembly 994. The illumination source 992 emits a beam (irradiation) of light energy. The illumination optical assembly 994 guides the beam of light energy from the illumination source 992 to the optical assembly 986. The beam illuminates selectively different portions of the reticle 788 and exposes the semiconductor wafer 990. In
The optical assembly 986 projects and/or focuses the light passing through the reticle to the wafer. Depending upon the design of the exposure apparatus 930, the optical assembly 986 can magnify or reduce the image illuminated on the reticle.
The reticle stage assembly 984 holds and positions the reticle 988 relative to the optical assembly 986 and the wafer 990. Similarly, the wafer stage assembly 910 holds and positions the wafer 990 with respect to the projected image of the illuminated portions of the reticle 988.
There are a number of different types of lithographic devices. For example, the exposure apparatus 930 can be used as scanning type photolithography system that exposes the pattern from the reticle 988 onto the wafer 990 with the reticle 988 and the wafer 990 moving synchronously. Alternatively, the exposure apparatus 930 can be a step-and-repeat type photolithography system that exposes the reticle 988 while the reticle 988 and the wafer 990 are stationary.
However, the use of the exposure apparatus 930 and the stage assemblies provided herein are not limited to a photolithography system for semiconductor manufacturing. The exposure apparatus 930, for example, can be used as an LCD photolithography system that exposes a liquid crystal display device pattern onto a rectangular glass plate or a photolithography system for manufacturing a thin film magnetic head. Further, the present invention can also be applied to a proximity photolithography system that exposes a mask pattern by closely locating a mask and a substrate without the use of a lens assembly. Additionally, the present invention provided herein can be used in other devices, including other semiconductor processing equipment, elevators, machine tools, metal cutting machines, inspection machines and disk drives.
As described above, a photolithography system according to the above described embodiments can be built by assembling various subsystems, including each element listed in the appended claims, in such a manner that prescribed mechanical accuracy, electrical accuracy, and optical accuracy are maintained. In order to maintain the various accuracies, prior to and following assembly, every optical system is adjusted to achieve its optical accuracy. Similarly, every mechanical system and every electrical system are adjusted to achieve their respective mechanical and electrical accuracies. The process of assembling each subsystem into a photolithography system includes mechanical interfaces, electrical circuit wiring connections and air pressure plumbing connections between each subsystem. Needless to say, there is also a process where each subsystem is assembled prior to assembling a photolithography system from the various subsystems. Once a photolithography system is assembled using the various subsystems, a total adjustment is performed to make sure that accuracy is maintained in the complete photolithography system. Additionally, it is desirable to manufacture an exposure system in a clean room where the temperature and cleanliness are controlled.
Further, semiconductor devices can be fabricated using the above described systems, by the process shown generally in
At each stage of wafer processing, when the above-mentioned preprocessing steps have been completed, the following post-processing steps are implemented. During post-processing, first, in step 1015 (photoresist formation step), photoresist is applied to a wafer. Next, in step 1016 (exposure step), the above-mentioned exposure device is used to transfer the circuit pattern of a mask (reticle) to a wafer. Then in step 1017 (developing step), the exposed wafer is developed, and in step 1018 (etching step), parts other than residual photoresist (exposed material surface) are removed by etching. In step 1019 (photoresist removal step), unnecessary photoresist remaining after etching is removed.
Multiple circuit patterns are formed by repetition of these preprocessing and post-processing steps.
While the particular stage assembly as shown and disclosed herein is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.
The application claims priority on Provisional Application Ser. No. 61/503,095 filed on Jun. 30, 2011, entitled “HYBRID COOLING AND THERMAL SHIELD FOR ELECTROMAGNETIC ACTUATORS”. As far as is permitted, the contents of U.S. Provisional Application Serial No. 61/503,095 are incorporated herein by reference.
Number | Date | Country | |
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61503095 | Jun 2011 | US |