248 nm紫外显微镜微纳线宽校准方法的研究

248 nm波长照明的紫外显微镜能够获得高达80 nm的光学分辨率,可以实现对掩模板的线宽和一维/二维栅格参数的测量。作为测量仪器的248 nm紫外显微镜需要对其进行校准。该显微镜测量范围在nm量级,校准使用400 nm一维栅格标准物质,通过对仪器不确定度和标准物质自身不确定度的评估,得到采集图像每个像素的扩展不确定度为0.178 nm,并给出了实际测量时的不确定度评价公式。

The Research of Nanometer Linewidth Calibration Method Used by 248 nm Ultraviolet Microscope

When utilizing 248 nm ultraviolet illumination, the microscope can attain as high as 80nm optical resolution, which can achieve the measurements of linewidth and one /two dimensional pitches of photomasks. But at present, the measurement uncertainty of 248 nm UV microscope is not known yet, it is need to do calibration for the instrument. Since the measurement range of 248 nm UV microscope is within nanometer range, it is reasonable to use 400 nm one dimensional pitches standard materials to do calibration. Through the estimation of instrument uncertainty and standard materials own uncertainty, it can calculate the expansion uncertainty of a single pixel which equals to 0.178 nm, and the uncertainty estimation formula of measurements are given.