测量位错密度常用方法之一是割线交点法,其公式为: Q=2 MN/1t式中Q—位错密度(cm/cm~3);M—照片的放大倍数;N—割线与位错线的交点数;1—照片上割线的长度(cm);t—薄膜厚度(cm)。这种测量方法产生误差的主要原因之一是难以选择适当的操作矢量gHKL以保证全部位错成象从而得到准确的 One of the common methods for measuring dislocation density is the secant intersection method, where Q = 2 MN / 1t where Q-dislocation density (cm / cm ~ 3); M- magnification of the picture; N-secant The number of intersection points with the dislocation line; 1- the length of the secant on the photograph (cm); t-the thickness of the film (cm). One of the major causes of this measurement error is the difficulty in selecting the appropriate vector gHKL to ensure that all dislocations are imaged to give accurate