使用原子力显微镜测量刻线边缘粗糙度的影响因素  

Influence factors of line edge roughness measured by AFM

作　　者：赵学增[1] 李宁[1] 周法权[1] 李洪波[1] 

机构地区：[1]哈尔滨工业大学机械电子工程学院,黑龙江哈尔滨150001

出　　处：《光学精密工程》2009年第4期839-848,共10页Optics and Precision Engineering

基　　金：2003年教育部留学回国人员科研启动基金资助项目;哈尔滨工业大学校基金资助项目(No.HIT.2002.28)

摘　　要：为了满足微电子制造技术中不断提高的刻线边缘粗糙度测量与控制精度的要求,对使用原子力显微镜(AFM)测量刻线边缘粗糙度的影响因素进行了研究。基于图像处理技术从单晶硅刻线样本的AFM测量图像中提取出线边缘粗糙度,并确定出其量化表征的参数。然后,根据线边缘粗糙度测量与表征的特点,对各种影响因素,包括探针针尖尺寸与形状的非理想性、AFM扫描图像的噪声、扫描采样间隔、压电晶体驱动精度、悬臂梁振动以及线边缘检测算法中的自由参数等进行了理论和实验分析,并分别提出了抑制及修正的方法。研究表明,在分析各种可能导致测量误差的影响因素的基础上,消除或减小其影响,可以提高刻线边缘粗糙度测量的准确度,为实现纳米尺度刻线形貌测量的精度要求提供理论与方法上的支持。In order to improve the measuring precision and controling precision of the Line Edge Roughness （LER） in microelectronics fabrication technologies, the influence factors of LER measurements for semiconductors using Atomic Force Microscope（AFM） is studied. Firstly, the LER features are extracted from an AFM image of single crystal silicon based on image processing techniques, and the parameters are determined to quantitatively characterize the LER features. Then, according to the characteristics of LER measurement and characterization method, the influence factors of LER measurements using AFM, including the nonideal properties of the sizes and shapes of probe tips, the signal noises of AFM images, scan sampling intervals, the driving precision of piezoelectricity, cantilever oscillation and the free parameters of edge detection algorithm and so on, are analyzed theoretically and experimentally,and the methods for restraining and amending the measuring errors are respectively proposed. The study indicates that a more precise measurement result for LERs using AFM can be obtained by eliminating or reducing the influences of various factors on measuring errors by proposed methods, which can provide a theoretical and methodologic support for improving the accuracy of nanometer-scale line structure topographic measurement.

关 键 词：纳米测量 线边缘粗糙度 原子力显微镜 测量误差分析 

分 类 号：TG84[金属学及工艺—公差测量技术] TH161[机械工程—机械制造及自动化]