Patent Number: 
Section: claims

1. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage, wherein a space between the wafer-side projection lens and the substrate stage defines a zone in which a beam from a grazing-incidence-type substrate-height measurement device propagates to and from the substrate between the wafer-side projection lens and the substrate, and the first magnetic shield defines a downstream-facing surface that is situated adjacent to but outside the zone. 2. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage;  a liner tube extending along the optical axis and having a downstream end;  a rotationally symmetrical lower first vacuum wall having an inside-diameter edge and a peripheral edge, the inside-diameter edge being attached circumferentially to the downstream end of the liner tube and extending radially between the wafer-side projection lens and the substrate stage; and  a rotationally symmetrical lower second vacuum wall having a cylindrical body portion extending upstream in an axial direction outside the wafer-side projection lens and a downstream edge attached circumferentially to the peripheral edge of the lower first vacuum wall, wherein the first magnetic shield extends along a downstream-facing surface of the lower first vacuum wall from the peripheral edge toward the optical axis. 3. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage;  at least one deflector situated radially inwardly of the wafer-side projection lens; and  a cylindrical deflector shield extending in an axial direction between the at least one deflector and the wafer-side projection lens, wherein the first magnetic shield has an inside-diameter edge having a diameter that is larger than an inside diameter of the deflector shield. 4. The apparatus of  claim 3 , wherein the deflector shield is a ferrite stack. claim 3 5. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage, wherein the first axis-facing surface is conical in profile, and the first magnetic shield has a multilayer structure including a non-magnetic body layer sandwiched between two ferromagnetic layers. 6. The apparatus of  claim 1 , wherein the reticle-side projection lens includes a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle. claim 1 7. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage;  wherein the reticle-side projection lens includes a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle; a space between the reticle-side projection lens and the reticle defines a zone in which a beam from a grazing-incidence-type reticle-height measurement device propagates to and from the reticle between the reticle-side projection lens and the reticle; and the second magnetic shield defines an upstream-facing surface that is situated adjacent to but outside the zone. 8. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle;  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate; and  a liner tube extending along the optical axis and having a downstream end;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage;  wherein the reticle-side projection lens includes a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle; the liner tube has an upstream end; the reticle-side projection lens further comprises a rotationally symmetrical upper first vacuum wall and a rotationally symmetrical upper second vacuum wall; the upper first vacuum wall includes an inside-diameter edge and a peripheral edge, the inside-diameter edge being attached circumferentially to the upstream end of the liner tube and extending between the reticle-side projection lens and the reticle; the upper second vacuum wall includes a cylindrical body portion extending downstream in an axial direction outside the reticle-side projection lens and an upstream edge attached circumferentially to the peripheral edge of the upper first vacuum wall; and the second magnetic shield extends along an upstream-facing surface of the upper first vacuum wall, from the peripheral edge toward the optical axis. 9. The apparatus of  claim 6 , further comprising: claim 6 a first deflector situated radially inwardly of the reticle-side projection lens; and  a cylindrical first deflector shield extending in an axial direction between the first deflector and the reticle-side projection lens. 10. The apparatus of  claim 9 , wherein the first deflector shield is a ferrite stack. claim 9 11. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle, and the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage;  a first deflector situated radially inwardly of the reticle-side projection lens;  a cylindrical first deflector shield extending in an axial direction between the first deflector and the reticle-side projection lens;  a second deflector situated axially between the reticle and the first deflector; and  a cylindrical second deflector shield situated radially outside the second deflector and extending in the axial direction, wherein the second magnetic shield comprises an inside-diameter edge adjacent the second axis-facing surface, the inside-diameter edge having a diameter that is larger than an inside diameter of the second deflector shield. 12. The apparatus of  claim 11 , wherein the second deflector shield is a ferrite stack. claim 11 13. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle, and the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage;  a second deflector situated radially inward of the reticle-side projection lens; and  a cylindrical second deflector shield extending in an axial direction between the second deflector and the reticle-side projection lens, wherein the second magnetic shield comprises an inside-diameter edge adjacent the second axis-facing surface, the inside-diameter edge having a diameter that is larger than an inside diameter of the second deflector shield. 14. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle, and the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage;  wherein the second magnetic shield has a multilayer structure including a non-magnetic body layer sandwiched between two ferromagnetic layers. 15. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle, and the wafer-side projection lens including a first magnetic shield having a first axis-facing surface that is rotationally symmetrical about the axis, the first magnetic shield being situated between a downstream-facing surface of the wafer-side projection lens and the substrate stage;  wherein the second axis-facing surface is conical in profile. 16. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle; and  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle;  wherein a space between the reticle-side projection lens and the reticle defines a zone in which a beam from a grazing-incidence-type reticle-height measurement device propagates to and from the reticle between the reticle-side projection lens and the reticle, and the second magnetic shield defines an upstream-facing surface that is situated adjacent to but outside the zone. 17. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle;  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle;  a liner tube extending along the optical axis and having an upstream end;  a rotationally symmetrical upper first vacuum wall having an inside-diameter edge and a peripheral edge, the inside-diameter edge being attached circumferentially to the upstream end of the liner tube and extending between the reticle-side projection lens and the reticle; and  a rotationally symmetrical upper second vacuum wall having a cylindrical body portion extending downstream in an axial direction outside the reticle-side projection lens and an upstream edge attached circumferentially to the peripheral edge of the upper first vacuum wall, wherein the second magnetic shield extends along an upstream-facing surface of the upper first vacuum wall from the peripheral edge toward the optical axis. 18. The apparatus of  claim 16 , further comprising: claim 16 a first deflector situated radially inwardly of the reticle-side projection lens; and  a cylindrical first deflector shield extending in an axial direction between the first deflector and the reticle-side projection lens. 19. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle;  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle;  a first deflector situated radially inwardly of the reticle-side projection lens;  a cylindrical first deflector shield extending in an axial direction between the first deflector and the reticle-side projection lens  a second deflector situated axially between the reticle and the first deflector; and  a cylindrical second deflector shield situated radially outside the second deflector and extending in the axial direction, wherein the second magnetic shield comprises an inside-diameter edge adjacent the second axis-facing surface, the inside-diameter edge having a diameter that is larger than an inside diameter of the second deflector shield. 20. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle;  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle;  a second deflector situated radially inwardly of the reticle-side projection lens; and  a cylindrical second deflector shield extending in an axial direction between the second deflector and the reticle-side projection lens, wherein the second magnetic shield comprises an inside-diameter edge adjacent the second axis-facing surface, the inside-diameter edge having a diameter that is larger than an inside diameter of the second deflector shield. 21. The apparatus of  claim 20 , wherein the second deflector shield is a ferrite stack. claim 20 22. A charged-particle-beam (CPB) microlithography apparatus, comprising: an illumination-optical system situated on an optical axis and configured to illuminate a region of a reticle, defining a pattern to be transferred to a sensitive substrate, with a charged particle illumination beam;  a reticle stage situated and configured to hold the reticle as the reticle is being illuminated by the illumination-optical system, wherein charged particles of the illumination beam passing through the illuminated region of the reticle constitute a patterned beam;  an imaging-optical system situated on the optical axis and configured to receive the patterned beam and project a demagnified focused image, on a sensitive substrate, of the illuminated region of the reticle;  a substrate stage situated and configured to hold the substrate as the patterned beam is projecting the image onto the substrate;  the imaging-optical system comprising a reticle-side electromagnetic projection lens and a wafer-side electromagnetic projection lens situated axially downstream of the reticle-side projection lens, the reticle-side projection lens including a second magnetic shield comprising a second axis-facing surface that is rotationally symmetrical about the optical axis, the second magnetic shield being situated between an upstream-facing surface of the reticle-side projection lens and the reticle;  wherein the second axis-facing surface is conical in profile; and the second magnetic shield has a multilayer structure including a non-magnetic body layer sandwiched between two ferromagnetic layers. 23. A process for manufacturing a microelectronic device, comprising the steps of: (a) preparing a wafer;  (b) processing the wafer; and  (c) assembling devices formed on the wafer during steps (a) and (b), wherein step (b) comprises the steps of (i) applying a resist to the wafer; (ii) exposing the resist; and (iii) developing the resist, and step (ii) comprises providing a CPB microlithography apparatus as recited in  claim 1 , and using the CPB microlithography apparatus to expose the resist with the pattern defined on the reticle.  claim 1 24. A microelectronic device produced by the method of  claim 23 . claim 23 25. A process for manufacturing a microelectronic device, comprising the steps of: (a) preparing a wafer;  (b) processing the wafer; and  (c) assembling devices formed on the wafer during steps (a) and (b), wherein step (b) comprises the steps of (i) applying a resist to the wafer; (ii) exposing the resist; and (iii) developing the resist, and step (ii) comprises providing a CPB microlithography apparatus as recited in  claim 17 , and using the CPB microlithography apparatus to expose the resist with the pattern defined on the reticle.  claim 17 26. A microelectronic device produced by the method of  claim 25 . claim 25