Inspection method and apparatus, and corresponding lithographic apparatus
    1.
    发明授权
    Inspection method and apparatus, and corresponding lithographic apparatus 有权
    检验方法和装置,以及相应的光刻设备

    公开(公告)号:US08749786B2

    公开(公告)日:2014-06-10

    申请号:US12902341

    申请日:2010-10-12

    IPC分类号: G01B11/00

    CPC分类号: G03F7/70633 G01N21/956

    摘要: A method and associated apparatus determine an overlay error on a substrate. A beam is projected onto three or more targets. Each target includes first and second overlapping patterns with predetermined overlay offsets on the substrate. The asymmetry of the radiation reflected from each target on the substrate is measured. The overlay error not resultant from the predetermined overlay offsets is determined. The function that enables calculation of overlay from asymmetry for other points on the wafer is determined by limiting the effect of linearity error when determining the overlay error from the function.

    摘要翻译: 方法和相关设备确定衬底上的覆盖误差。 光束投影到三个或更多个目标上。 每个目标包括在衬底上具有预定覆盖偏移的第一和第二重叠图案。 测量从基板上的每个目标反射的辐射的不对称性。 确定不是从预定的覆盖偏移产生的覆盖误差。 通过限制从功能确定覆盖误差时线性误差的影响,可以确定能够计算晶片上其他点不对称的叠加的功能。