Asml Netherlands B.v.

Sven Gunnar Krister Magnusson

Gerardus Carolus Johannus Hofmans

Frank Staals

Hubertus Antonius Geraets

Hans Van Der Laan

Mark Zellenrath

Hans Butler

Wim Tjibbo Tel

Martin Jules Marie-Emile De Nivelle

A method of calibrating an inspection apparatus. Obtaining a surface level measurements (LS) at respective level sensing locations LS(x,y). Determining focus settings (LP, LP) for exposure field regions (EF, EF) in accordance with surface level measurements (LS, LS) having level sensing locations corresponding to the respective exposure field region. Exposing exposure field regions (EF, EF) with focus offsets (FO, FO) defined with reference to the respective focus settings (LP, LP) to produce target patterns at respective target locations. Obtaining focus-dependent property measurements, such as Critical Dimension (CD) and/or side wall angle (SWA) of the target patterns measured using the inspection apparatus; and calibrating the inspection apparatus using the focus-dependent property measurements (CD/SWA) and the respective focus offsets (FO, FO). The calibration uses surface level measurements (e.g., LS()) having a level sensing location (e.g., LSL()) corresponding to the respective target location (TL). Each offset value is thus corrected in the calibration for the local wafer stack unflatness present during exposure.

Calibration method and inspection apparatus

Movements of a lithographic apparatus include dynamic positioning errors on one or more axes which cause corresponding errors which can be measured in the applied pattern. A test method includes operating the apparatus several times while deliberately imposing a relatively large dynamic positioning error at different specific frequencies and axes. Variations in the error in the applied pattern are measured for different frequencies and amplitudes of the injected error across a frequency band of interest for a given axis or axes. Calculation using said measurements and knowledge of the frequencies injected allows analysis of dynamic positioning error variations in frequency bands correlated with each injected error frequency.

Method of measuring properties of dynamic positioning errors in a lithographic apparatus, data processing apparatus, and computer program product

A method of measuring focus of a lithographic projection apparatus includes exposure of a photoresist covered test substrate with a plurality of verification fields. Each of the verification fields includes a plurality of verification markers, and the verification fields are exposed using a predetermined focus offset. After developing, an alignment offset for each of the verification markers is measured and translated into defocus data using a transposed focal curve.

Method of measuring focus of a lithographic projection apparatus

A method of measuring focus of a lithographic projection apparatus includes exposure of a photoresist covered test substrate with a plurality of verification fields. Each of the verification fields includes a plurality of verification markers, and the verification fields are exposed using a predetermined focus offset FO. After developing, an alignment offset for each of the verification markers is measured and translated into defocus data using a transposed focal curve. The method according to an embodiment of the invention may result in a focus-versus alignment shift sensitivity up to 50 times higher (typically dX,Y/dZ=20) than conventional approaches.

A method of measuring a lithographic projection apparatus is described. The method includes imaging a verification mark of a patterning device onto a radiation-sensitive layer held by a substrate table of a lithographic apparatus, wherein the verification mark includes at least a first, a second and a third verification structure that have a mutually different sensitivity profile for a dose setting, a focus setting and a contrast setting.

Method of measuring a lithographic projection apparatus

A lithographic apparatus includes an illumination system to condition a radiation beam; a patterning device support to support a patterning device, the patterning device capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam; a substrate table constructed to hold a substrate, and a projection system to project the patterned radiation beam in a scanning exposure along a scanning direction onto a target portion of the substrate. The illumination system is configured to form in a plane of the patterning device a slit shaped image. The slit shaped image has a curved shape with a slit curvature in the scanning direction, with a length in the scanning direction and a width perpendicular to the scanning direction. The slit shaped image is configured to create a curved pattern image portion of the patterned radiation beam in an image plane of the projection system.

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Veldhoven, Netherlands

Sven Gunnar Krister Magnusson