Abstract: A method and apparatus make use of data representing changes in wavelength of a radiation source to provide control of focal plane position or to provide correction of sensor data. In the first aspect, the wavelength variation data is provided to control systems that control focus by moving apparatus components including, for example, the mask table, the substrate table or optical elements of the projection optical system. In the second aspect, variation data is used in correcting, e.g., focal plane position data measured by an inboard sensor, such as a transmitted image sensor. The two aspects may be combined in a single apparatus or may be used separately.

Abstract: A method and apparatus make use of data representing changes in wavelength of a radiation source to provide control of focal plane position or to provide correction of sensor data. In the first aspect, the wavelength variation data is provided to control systems that control focus by moving apparatus components including, for example, the mask table, the substrate table or optical elements of the projection optical system. In the second aspect, variation data is used in correcting, e.g., focal plane position data measured by a transmitted image sensor. The two aspects may be combined in a single apparatus or may be used separately.

Abstract: A CD-pitch dependency for a lithographic pattern printing process is related to the spectral intensity distribution of radiation used for projecting the pattern. A CD-pitch dependency can vary from one system to another. This can result in an iso-dense bias mismatch between systems. The invention addresses this problem by providing a lithographic apparatus including an illumination system for providing a projection beam of radiation, a projection system for projecting a patterned beam onto a target portion of a substrate, and a substrate table for holding the substrate, with a controller to provide an adjustment of the spectral distribution of radiant intensity of the projection beam. The adjustment of the spectral intensity distribution is based on data relating to an iso dense bias, and comprises a broadening of the spectral bandwidth or a change of shape of the spectral intensity distribution.