Patent Number: 
Section: claims

1. In a charged-particle-beam microlithography apparatus that irradiates a pattern-defining reticle with a charged particle beam passing through an illumination-optical system such that particles of the beam pass through the reticle, and that passes the beam transmitted through the reticle through a projection-optical system so as to projection-transfer the reticle pattern onto a wafer, a system for producing a hollow beam, comprising: a scattering aperture situated at a crossover-image plane of the illumination-optical system, the scattering aperture being configured as one or more openings defined in a layer of beam-scattering material, the openings being arranged to have, collectively, a first radius equal to a radius of a central region of the scattering aperture and a second radius greater than the first radius so as to produce a hollow beam downstream of the scattering aperture as the beam passes through the openings; and  a blocking aperture situated between the scattering aperture and the reticle, the blocking aperture being configured as a plate defining a central opening, the plate being configured to absorb charged particles of the beam that were scattered by passage through the scattering aperture. 2. The system of  claim 1 , further comprising a current-limiting aperture upstream of the scattering aperture, the current-limiting aperture being configured to pre-absorb particles of the charged particle beam at an edge of the beam. claim 1 3. The system of  claim 1 , further comprising a scattered-particle-absorbing aperture, configured as a particle-absorbing plate defining a central void, and configured to be situated between the blocking aperture and the reticle. claim 1 4. A charged-particle-beam microlithography apparatus comprising the system of  claim 1 . claim 1 5. A method for manufacturing a semiconductor device, comprising performing projection-transfer of a pattern, defined by a reticle, onto a wafer using a charged-particle-beam microlithography apparatus as recited in  claim 4 . claim 4 6. The system of  claim 1 , wherein the scattering aperture is configured as voids defined in a beam-scattering plate. claim 1 7. The system of  claim 6 , wherein the voids collectively define a profile that is substantially ring-shaped. claim 6 8. The system of  claim 1 , wherein the scattering aperture is configured as an opening in a layer of charged-particle-beam-scattering material on a relatively charged-particle-beam-transmissive membrane. claim 1 9. The system of  claim 8 , wherein the opening is ring-shaped. claim 8