Method and device for monitoring multiple mirror arrays in an illumination system of a microlithographic projection exposure apparatus

摘要

Microlithographic illumination system includes individually drivable elements to variably illuminate a pupil surface of the system. Each element deviates an incident light beam based on a control signal applied to the element. The system also includes an instrument to provide a measurement signal, and a model-based state estimator configured to compute, for each element, an estimated state vector based on the measurement signal. The estimated state vector represents: a deviation of a light beam caused by the element; and a time derivative of the deviation. The illumination system further includes a regulator configured to receive, for each element: a) the estimated state vector; and b) target values for: i) the deviation of the light beam caused by the deviating element; and ii) the time derivative of the deviation.

主权项

1. A monitoring device for monitoring an arrangement of beam deviating elements positioned in a first plane, the device comprising:
a detector positioned in a second plane; a Fourier optical system positioned to direct light from the arrangement of beam deviating elements to the detector; and an evaluation device coupled to the detector and configured to provide information about an alignment of one or more of the beam deviating elements based on a signal from the detector; wherein the second plane is a Fourier plane of the Fourier optical system, and wherein the first and second planes are neither parallel, nor perpendicular.