论文部分内容阅读
集成电路投影曝光设备中的对准装置包括观察硅片和掩模表面参考标记用的投影透镜系统。硅片上的标记是一组一个方向具有预定周期的周期图形结构;掩模上的标记可以相对于硅片参考标记调整定位。投影系统能通过掩模在硅片表面形成可见光图象。该装置还包括用作探测从硅片表面穿过投影透镜系统的反射光的观察光学系统。该装置还能选择硅片上参考标记图形形成的衍射光的特殊分量,并把这些特殊分量引入观察光学系统。在该套装置的观察光学系统的光瞳附近设置了遮光元件。它是一带状传光孔,在与硅片表面上的周期性参考标记垂直的方向延伸分布。
Alignment devices in integrated circuit projection exposure apparatus include a projection lens system for viewing reference marks on a wafer and a mask surface. The marks on the wafer are a set of periodic pattern structures having a predetermined period in one direction; the marks on the mask can be positioned relative to the silicon reference marks. Projection system through the mask in the silicon surface to form a visible light image. The device also includes an observation optical system for detecting reflected light that passes through the projection lens system from the surface of the wafer. The device can also select specific components of the diffracted light formed by the reference mark pattern on the wafer and introduce these special components into the viewing optical system. A light-shielding member is provided in the vicinity of the pupil of the observation optical system of the apparatus. It is a ribbon aperture that extends in a direction perpendicular to the periodic reference mark on the wafer surface.