首页>
外国专利>
Method for focus detection for optically detecting deviation of the image plane of a projection lens from the upper surface of a substrate, and an imaging system with a focus-detection system
Method for focus detection for optically detecting deviation of the image plane of a projection lens from the upper surface of a substrate, and an imaging system with a focus-detection system
展开▼
机译:用于光学地检测投影透镜的像面与基板的上表面的偏离的焦点检测方法以及具有焦点检测系统的摄像系统
展开▼
页面导航
摘要
著录项
相似文献
摘要
A microlithographic projection illumination system has a focus-detection system for optically detecting deviations of the image plane of a projection lens from the upper surface of a substrate arranged in the vicinity of its image plane. The focus-detection system has a system for coupling in at least one measuring beam that is obliquely incident on, and to be reflected at, the substrate surface into an intermediate zone between the final optical surface of the imaging system and the substrate surface and a system for coupling out the measuring beam and detecting it following its reflection at the substrate surface. The system for coupling the measuring beam in and the system for coupling it out are configured such that the measuring beam is reflected at least once at the substrate surface and at least once at a reflecting surface of the imaging system that reflects the light employed for measurement purposes before the measuring beam enters the system for coupling it out, which allows employing the image side of the imaging system as part of the focus-detection system. The focus-detection system also operates reliably when used on ultrahigh-aperture lenses that have correspondingly short working distances.
展开▼