基于图像处理的线距测量方法

Line Spacing Measurement Method Based on Image Processing

关键尺寸扫描电镜(CD-SEM)是对微纳尺寸线距标准样片定标的标准器具。为提高标准样片的定标准确度,研究一种基于图像处理技术的测量算法。首先,对研制样片的特征进行分析;其次,研究线性近似算法和线距测量算法,并分别对100nm^10μm的线距标准样片进行测量;最后,利用纳米测量机进行对比实验研究。实验结果表明,线性近似算法的相对误差可以控制在0.45%以内,相比之下,线距测量算法的相对误差可控制在0.35%以内。因此,线距测量算法提高了线距的测量精度,为提高线距测量类仪器量值的可靠性、保证半导体器件制造精度提供了一种测量方案。

The critical dimension scanning electron microscope(CD-SEM)is a standard instrument for standardizing micro-to nano-sized line spacing samples.To improve the calibration accuracy of samples,this paper studies a measurement algorithm based on image processing technology.First,the characteristics of the developed samples are analyzed.Second,the algorithms for micro-to nano-sized line spacing measurement and linear approximation are researched and the line spacing standard samples with a single period from 100 nm to^10μm are measured.Finally,a nano-measuring machine is used in comparative experiments.The experimental results show that the relative error of the linear approximation algorithm is controlled within 0.45%.In contrast,the relative error obtained by the line spacing measurement algorithm is controlled within 0.35%,thus improving the measurement accuracy of the line spacing.The algorithm provides a measurement scheme for improving the reliability of the line spacing measurement instrument and ensuring the precision of semiconductor device manufacturing.