Source: http://www.google.de/patents/US20060017893
Timestamp: 2013-12-05 02:39:57
Document Index: 103629806

Matched Legal Cases: ['art 101', 'art 101', 'art 101', 'art 101', 'art 101', 'Application No. 03257072']

Patent US20060017893 - Lithographic apparatus - Google PatenteSuche Bilder Maps Play YouTube News Gmail Drive Mehr » Erweiterte Patentsuche | Anmelden Erweiterte Patentsuche PatenteIn an immersion-type lithographic apparatus, in which a surface of a substrate is immersed in liquid during an exposure operation, the substrate is held against a substrate table. On completion of the exposure operation, the substrate is lifted clear of the substrate table. In order to overcome a tendency...http://www.google.de/patents/US20060017893?utm_source=gb-gplus-sharePatent US20060017893 - Lithographic apparatus Ver�ffentlichungsnummerUS20060017893 A1PublikationstypAnmeldung AnmeldenummerUS 10/895,998 Ver�ffentlichungsdatum26. Jan. 2006Eingetragen22. Juli 2004 Priorit�tsdatum22. Juli 2004Auch ver�ffentlicht unterUS7161663 Ver�ffentlichungsnummer10895998, 895998, US 2006/0017893 A1, US 2006/017893 A1, US 20060017893 A1, US 20060017893A1, US 2006017893 A1, US 2006017893A1, US-A1-20060017893, US-A1-2006017893, US2006/0017893A1, US2006/017893A1, US20060017893 A1, US20060017893A1, US2006017893 A1, US2006017893A1 ErfinderJeroen Johannes Mertens, Sjoerd Nicolaas Donders, Christiaan Hoogendam, Bob StreefkerkUrspr�nglich Bevollm�chtigterAsml Netherlands B.V. Referenziert von (10), Klassifizierungen (7), Juristische Ereignisse (2) Externe Links: USPTO, USPTO-Zuordnung, EspacenetLithographic apparatusUS 20060017893 A1 Zusammenfassung In an immersion-type lithographic apparatus, in which a surface of a substrate is immersed in liquid during an exposure operation, the substrate is held against a substrate table. On completion of the exposure operation, the substrate is lifted clear of the substrate table. In order to overcome a tendency caused by a film of residual liquid to cause the substrate to stick to the substrate table, pins used to lift the substrate are arranged and operated so that, at least initially, force is applied to the substrate at a location offset from its central axis. Bilder(6) Anspr�che(19)
DETAILED DESCRIPTION FIG. 1 schematically depicts a lithographic apparatus according to a particular embodiment of the invention. The apparatus comprises: an illumination system (illuminator) IL for providing a projection beam PB of radiation (e.g. UV radiation). a first support structure (e.g. a mask table) MT for supporting patterning device (e.g. a mask) MA and connected to first positioner PM for accurately positioning the patterning device with respect to item PL; a substrate table (e.g. a wafer table) WT for holding a substrate (e.g. a resist-coated wafer) W and connected to second positioner PW for accurately positioning the substrate with respect to item PL; and a projection system (e.g. a refractive projection lens) PL for imaging a pattern imparted to the projection beam PB by patterning device MA onto a target portion C (e.g. comprising one or more dies) of the substrate W. As here depicted, the apparatus is of a transmissive type (e.g. employing a transmissive mask). Alternatively, the apparatus may be of a reflective type (e.g. employing a programmable mirror array of a type as referred to above). The illuminator IL receives a beam of radiation from a radiation source SO. The source and the lithographic apparatus may be separate entities, for example when the source is an excimer laser. In such cases, the source is not considered to form part of the lithographic apparatus and the radiation beam is passed from the source SO to the illuminator IL with the aid of a beam delivery system BD comprising for example suitable directing mirrors and/or a beam expander. In other cases the source may be integral part of the apparatus, for example when the source is a mercury lamp. The source SO and the illuminator IL, together with the beam delivery system BD if required, may be referred to as a radiation system. The illuminator IL may comprise adjusting means AM for adjusting the angular intensity distribution of the beam. Generally, at least the outer and/or inner radial extent (commonly referred to as σ-outer and σ-inner, respectively) of the intensity distribution in a pupil plane of the illuminator can be adjusted. In addition, the illuminator IL generally comprises various other components, such as an integrator IN and a condenser CO. The illuminator provides a conditioned beam of radiation, referred to as the projection beam PB, having a desired uniformity and intensity distribution in its cross-section. The projection beam PB is incident on the mask MA, which is held on the mask table MT. Having traversed the mask MA, the projection beam PB passes through the lens PL, which focuses the beam onto a target portion C of the substrate W. With the aid of the second positioner PW and position sensor IF (e.g. an interferometric device), the substrate table WT can be moved accurately, e.g. so as to position different target portions C in the path of the beam PB. Similarly, the first positioner PM and another position sensor (which is not explicitly depicted in FIG. 1) can be used to accurately position the mask MA with respect to the path of the beam PB, e.g. after mechanical retrieval from a mask library, or during a scan. In general, movement of the object tables MT and WT will be realized with the aid of a long-stroke module (coarse positioning) and a short-stroke module (fine positioning), which form part of the positioners PM and PW. However, in the case of a stepper (as opposed to a scanner) the mask table MT may be connected to a short stroke actuator only, or may be fixed. Mask MA and substrate W may be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2. The depicted apparatus can be used in the following preferred modes: 1. In step mode, the mask table MT and the substrate table WT are kept essentially stationary, while an entire pattern imparted to the projection beam is projected onto a target portion C at one time (i.e. a single static exposure). The substrate table WT is then shifted in the X and/or Y direction so that a different target portion C can be exposed. In step mode, the maximum size of the exposure field limits the size of the target portion C imaged in a single static exposure. 2. In scan mode, the mask table MT and the substrate table WT are scanned synchronously while a pattern imparted to the projection beam is projected onto a target portion C (i.e. a single dynamic exposure). The velocity and direction of the substrate table WT relative to the mask table MT is determined by the (de-)magnification and image reversal characteristics of the projection system PL. In scan mode, the maximum size of the exposure field limits the width (in the non-scanning direction) of the target portion in a single dynamic exposure, whereas the length of the scanning motion determines the height (in the scanning direction) of the target portion. 3. In another mode, the mask table MT is kept essentially stationary holding a programmable patterning device, and the substrate table WT is moved or scanned while a pattern imparted to the projection beam is projected onto a target portion C. In this mode, generally a pulsed radiation source is employed and the programmable patterning device is updated as required after each movement of the substrate table WT or in between successive radiation pulses during a scan. This mode of operation can be readily applied to maskless lithography that utilizes a programmable patterning device, such as a programmable mirror array of a type as referred to above. Combinations and/or variations on the above described modes of use or entirely different modes of use may also be employed. FIGS. 5 and 6 illustrate a typical substrate release mechanism of a substrate table. In FIG. 5, the substrate table 100 comprises a substrate table part 101 made of a material having substantially zero thermal coefficient of expansion such as Zerodur, atop of which is a so-called pimple- or burl-plate 102. The cross-section of FIG. 5 is taken along the line X-X in FIG. 6. Defined vertically through the table part 101 and plate 102 are three through-holes 103 a-c which allow pins, described below and that are part of the substrate release mechanism, to come into engagement with the lower surface of the substrate during, for example, a releasing operation. The upper major surface of the plate 102 has a recessed surface which defines, together with the lower major face of the substrate, a laminar underpressure chamber which, because of its small height, is not convenient to show in FIGS. 5 and 6. When the substrate W is to be held against the plate 102, this chamber is evacuated by means of a pump (not shown) and passageways (also not shown) through the table part 101 and plate 102. FIG. 6 is a top view of the plate 102 showing the upper major surface thereof. It has a continuous outer rim 105, which seals the underpressure chamber from the exterior, three collars 106 a-c, which surround the through-holes 103 a-c for the pins and prevent gaseous leakage into the chamber through them, a multiplicity of small protrusions 107, which are also known as �pimples�, extending from the upper major surface of the plate 102 and arrayed uniformly across the recessed part of the plate to provide support for the substrate (against the action of the vertical differential pressure), and downwardly-directed through-holes (not shown) defined through the body of the plate to connect the chamber to a vacuum pump. The plate 102 is manufactured such that the upper surfaces of the rim 105, pimples 107 and collars 106 a-c are substantially co-planar so as to define essentially a single, horizontal plane of support for the substrate W. The through-holes 103 are arranged symmetrically, at the vertices of an equilateral triangle centered on the central vertical axis Zc of the substrate table 100 and of the substrate W. The axis Zc substantially coincides with the center of gravity of the substrate W. Coaxially within these through-holes 103, and consequently similarly symmetrically arranged, are three pins 108 a-c which are of equal length and held by a rigid carrier plate 109 below and substantially parallel to the plate 102 and table part 101. The upper extremities of the pins, which in this case are circular surfaces, coincide in a horizontal plane, which is substantially parallel to the lower face of the substrate. As used herein, the terms pin or pins include any type of projection (of any length) or discrete support surface. Once the pressure in the underpressure chamber has been increased, the pins may be driven upwardly, e.g. by moving the carrier plate 109 upwardly from the position shown in FIG. 5, to lift the substrate from the plate 102. As described above, residual liquid RL remaining from immersion of the substrate may extend around all or part of the periphery of the lower face of the substrate and cause a tendency for the substrate W to stick to the plate 102. FIGS. 7 and 8 show substrate release mechanisms according to embodiments of the invention. The structure and operation of these embodiments are the same as for the mechanism of FIGS. 5 and 6, except as specifically noted hereafter. In the embodiment of FIG. 7, in addition to the group of three pins 108 a-c already described, there is an additional, independently actuable pin 208 and associated through-hole 203 defined through table part 101 and plate 102. The linear motor actuator 210 associated with the additional pin 208 is operated in timed relationship to the linear motor actuator 211 associated with the group of three pins 108 a-c such that the additional pin 208 comes into contact with, and starts pushing against, the lower face of the substrate W before any of the other pins 108 a-c do. The substrate thus initially experiences an upward force which is offset along a radius from the central vertical axis Zc. This has the effect of slightly tilting the substrate so that the residual liquid film around the substrate edge portion adjacent the additional pin tends to separate, while the diametrical opposite edge portion of the substrate reduces the thickness of the film in that region. This can overcome the sticking action of the substrate W against the plate 102. Thereafter, the linear actuator 211 of the pins 108 a-c is activated, causing these to project through their respective through holes and push against the underside of the substrate, lifting the substrate clear of the plate. As shown in FIG. 9, the tines 220 a, 220 b of a motor-driven carrier fork 220 can then be inserted under the substrate W and the actuators 210, 211 can be operated to retract the pins so that the substrate W settles onto the fork 220 and can be carried away for further processing. The actuators 210, 211 of the pins may be linear electric motors e.g. of the well-known voice-coil type. FIG. 10 shows schematically circuitry 400 which may be associated with such motors to coordinate their operation. An actuator sequencer 401, which may be implemented by analog or digital circuitry or by operation of software responds to a signal which is applied to an input 402 when a substrate release operation is to begin. The sequencer 401 controls and coordinates the energizing of the armature coils 403, 404 of motors 210, 211 via power amplifier stages 405, 406 such that, in response to that signal, the motor 210 associated with the additional pin 208 activates first so as to push the pin 208 against the substrate W, as described above, to overcome the sticking effect. Then, after a suitable time interval to allow that to occur, the motor 211 of the pins 108 a-c is activated to lift the substrate W clear of the plate 102; the pin 208 can be withdrawn once the substrate is resting on the pins 108 a-c. FIG. 8 shows a further embodiment of the invention in which, as in FIG. 5, there is no additional pin 208, just the group of pins 108 a-c. Instead, in order to facilitate the release of the substrate W, one, 108 a, of the pins is made very slightly longer than the others, 108 b,c (this difference in length is exaggerated in FIG. 8 for ease of illustration and in practice may be of the order of 10 μm, preferably not more than 5 mm). The top face of that pin 108 a consequently stands higher than those of the other pins and so comes into contact with the underside of the substrate before the others do. This effects the tilting movement as described with reference to FIG. 7 and overcomes the sticking of the substrate to the plate. Further upward movement of the group of pins 108 a-c brings the other pins 108 b,c into contact with the underside of the substrate lifting it clear of the plate 102 and allowing the insertion of the carrier fork 220 as in FIG. 7. In both embodiments, e.g., as depicted in FIGS. 7 and 8, the substrate is initially acted upon by a pin force which is offset from the axis Zc and overcomes the sticking effect caused by any residual liquid around the periphery of the substrate. Numerous variants of the above which are within the scope of the appended claims will be apparent to those skilled in the art. For example, although in the embodiments above, the pins are passive, fixed length, elements whose movement is effected by a linear actuator acting upon and moving their carrier(s), other methods of driving the pins are possible. In one implementation, the pin carrier(s) remain stationary and instead each pin is mounted to its carrier via an individual linear motor; the operation of these motors is then coordinated to give the pin movements described with reference to FIGS. 7 and 8. An alternative way of creating an asymmetric force on the substrate W would be to have an asymmetric arrangement of pins. Three pins could be arranged, for example, in an isosceles triangle with one pin significantly closer to the circumference of the substrate W. Also, there is no limitation as to the number of pins. Although three pins are required to define a support plane for the substrate, there need not be three pins in a central group: for example, an additional, offset pin such as 208, could act as the third pin for the purpose of stabilizing and lifting the substrate. Alternatively or additionally, there could be more than three pins in a central, symmetrical, group around the axis Zc. Likewise, there need not be only one pin used to cause the initial, asymmetrical tilting force on the substrate. To reduce the force required to release the substrate W, the materials used for plate 102 can be chosen to minimize the capillary action and surface tension adhering the substrate W to the plate 102. For example, a hydrophobic material could be used to coat the plate 102. As used herein, a substrate positioner includes any device to move the substrate into contact (whether in whole or in part) with a surface of the substrate table and/or out of contact (whether in whole or in part) with a surface of the substrate table. Such a device may use mechanical, electrical, magnetic, vacuum, etc. force to displace the substrate and may include, without limitation, any actuator, motor, magnetic arrangement, pump, etc. to provide the force. In the case of mechanical force, such force may be applied to the substrate using any type of component including pins, plates, shafts, etc. The substrate positioner includes without limitation any of the embodiments disclosed herein such as a substrate release mechanism described above comprising an actuator(s) and pins. Another liquid supply system which has been proposed is to provide the liquid supply system with a seal member which extends along at least a part of a boundary of the space between the final element of the projection system and the substrate table. The seal member is substantially stationary relative to the projection system in the XY plane though there may be some relative movement in the Z direction (in the direction of the optical axis). A seal is formed between the seal member and the surface of the substrate. In an embodiment, the seal is a contactless seal such as a gas seal. Such a system with a gas seal is disclosed in U.S. patent application Ser. No. 10/705,783, hereby incorporated in its entirety by reference. A further immersion lithography solution with a localized liquid supply system is shown in FIG. 4. Liquid is supplied by two groove inlets IN on either side of the projection system PL and is removed by a plurality of discrete outlets OUT arranged radially outwardly of the inlets IN. The inlets IN and OUT can be arranged in a plate with a hole in its center and through which the projection beam is projected. Liquid is supplied by one groove inlet IN on one side of the projection system PL and removed by a plurality of discrete outlets OUT on the other side of the projection system PL, causing a flow of a thin film of liquid between the projection system PL and the substrate W. The choice of which combination of inlet IN and outlets OUT to use can depend on the direction of movement of the substrate W (the other combination of inlet IN and outlets OUT being inactive). In European Patent Application No. 03257072.3, the idea of a twin or dual stage immersion lithography apparatus is disclosed. Such an apparatus is provided with two tables for supporting a substrate. Leveling measurements are carried out with a table at a first position, without immersion liquid, and exposure is carried out with a table at a second position, where immersion liquid is present. Alternatively, the apparatus has only one table. While specific embodiments of the invention have been described above, it will be appreciated that the invention may be practiced otherwise than as described. The description is not intended to limit the invention. Referenziert von Zitiert von PatentEingetragen Ver�ffentlichungsdatum Antragsteller TitelUS750849422. Dez. 200624. M�rz 2009Asml Netherlands B.V.Lithographic apparatus and a subtrate table for exciting a shockwave in a substrateUS759309615. Mai 200622. Sept. 2009Asml Netherlands B.V.Lithographic apparatus and device manufacturing methodUS7933000 *16. Nov. 200626. Apr. 2011Asml Netherlands B.V.Device manufacturing method, method for holding a patterning device and lithographic apparatus including an applicator for applying molecules onto a clamp area of a patterning deviceUS80522897. Juni 20068. Nov. 2011Asml Netherlands B.V.Mirror array for lithographyUS8400617 *24. M�rz 201019. M�rz 2013Asml Netherlands B.V.Lithographic apparatus having a substrate support with open cell plastic foam partsUS20100271611 *24. M�rz 201028. Okt. 2010Asml Netherlands B.V.Lithographic apparatus having a substrate support with open cell plastic foam partsEP1857881A1 *1. Mai 200721. Nov. 2007ASML Netherlands B.V.Lithographic apparatus and device manufacturing methodEP1865359A1 *29. Mai 200712. Dez. 2007ASML Netherlands B.V.Cooled mirror array for lithographyEP1923743A2 *15. Nov. 200721. Mai 2008ASML Netherlands B.V.Lithographic apparatus and device manufacturing methodWO2008078995A1 *18. Dez. 20073. Juli 2008Asml Netherlands BvLithographic apparatus, substrate table, and method for releasing a wafer* Vom Pr�fer zitiertKlassifizierungen US-Klassifikation355/30, 355/53Internationale KlassifikationG03B27/52 UnternehmensklassifikationG03F7/70341, G03F7/707 Europ�ische KlassifikationG03F7/70N2, G03F7/70F24Juristische Ereignisse DatumCodeEreignisBeschreibung30. Juni 2010FPAYFee paymentYear of fee payment: 421. Okt. 2004ASAssignmentOwner name: ASML NETHERLANDS B.V., NETHERLANDSFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:MERTENS, JEROEN JOHANNES SOPHIA MARIA;DONDERS, SJOERD NICOLAAS LAMBERTUS;HOOGENDAM, CHRISTIAAN ALEXANDER;AND OTHERS;REEL/FRAME:015916/0571;SIGNING DATES FROM 20041011 TO 20041015DrehenOriginalbildGoogle-Startseite - Sitemap - USPTO-Bulk-Downloads - Datenschutzerkl�rung - Nutzungsbedingungen - �ber Google Patente - Feedback gebenDaten bereitgestellt von IFI CLAIMS Patent Services.© 2012 Google