Abstract: A scatterometer for measuring a property of a substrate includes a focus sensing arrangement including an arrangement (65) that directs a first beam of radiation onto a focusing arrangement, to be detected by a focus sensor arrangement (61). A focus controller (67) provides control signals representative of the relative positions of the focusing arrangement (15, 69) and the substrate (W), which are required to focus the first beam of radiation on the substrate. An actuator arrangement adjusts the position of the focusing arrangement dependent on the control signals. An irradiation arrangement directs a second beam of radiation onto the substrate using the focusing arrangement, a measurement detector (18) detecting the second radiation beam after reflection from the substrate. A focus offset arrangement adjusts the focus produced by the focusing arrangement to compensate for an offset between the focusing of the first beam of radiation and the second beam of radiation.

Abstract: A scatterometer for measuring a property of a substrate includes a focus sensing arrangement including an arrangement (65) that directs a first beam of radiation onto a focusing arrangement, to be detected by a focus sensor arrangement (61). A focus controller (67) provides control signals representative of the relative positions of the focusing arrangement (15, 69) and the substrate (W), which are required to focus the first beam of radiation on the substrate. An actuator arrangement adjusts the position of the focusing arrangement dependent on the control signals. An irradiation arrangement directs a second beam of radiation onto the substrate using the focusing arrangement, a measurement detector (18) detecting the second radiation beam after reflection from the substrate. A focus offset arrangement adjusts the focus produced by the focusing arrangement to compensate for an offset between the focusing of the first beam of radiation and the second beam of radiation.

Abstract: An inspection apparatus configured to measure a property of a substrate includes an illumination source, a beam splitter, a first polarizer positioned between the illumination source and the beam splitter, an objective lens and an optical device that alters a polarization state of radiation traveling through it positioned between the beam splitter and the substrate and a second polarizer positioned between the beam splitter and a detector. An axis of the second polarizer is rotated with respect to an axis of the first polarizer. Radiation polarized by the first polarizer that reflects off any optical elements between the beam splitter and the optical device is prevented from entering the detector by the second polarizer. Only radiation that passes twice through the optical device has its polarization direction rotated so that it passes through the second polarizer and enters the detector.

Abstract: An optical integrator for an illumination device of a microlithographic projection exposure system has a rod made of a material transparent for ultraviolet light and with a rectangular cross-section. A rod arrangement with, for example, seven small rods made of the same material is arranged before the entrance surface of the rod. The aspect ratio between width and height of the small rods is the inverse of the aspect ratio between width and height of the rod. The rod arrangement, or some analogous structure, surface or treatment substituted therefor, serves to compensate the direction-dependent total reflection losses of the rod.

Abstract: An optical integrator for an illumination device of a microlithographic projection exposure system has a rod made of a material transparent for ultraviolet light and with a rectangular cross-section. A rod arrangement with, for example, seven small rods made of the same material is arranged before the entrance surface of the rod. The aspect ratio between width and height of the small rods is the inverse of the aspect ratio between width and height of the rod. The rod arrangement, or some analogous structure, surface or treatment substituted therefor, serves to compensate the direction-dependent total reflection losses of the rod.