Fabricating Parameters Optimization of High Frequency Grating by Multi-scanning Electron Beam Method

The electron-beam moiré method uses a high frequency grating to measure microscopic deformation. Increasingly fine gratings are being developed to achieve increasingly high resolutions in microscopic stress analysis. In this study, we improve the electron grid fabricating technique by using a common scanning electron microscope (SEM). An error analysis for the multi-scanning grating was performed by a sampling moiré method. The grating manufacturing parameters strongly affect the superfine grating quality. A high accelerating voltage or a short working distance yield better results generally. A set of optimal parameters is suggested based on a minimum-error criterion. A cross-line grid with a frequency of 10,000 lines/mm and a parallel grating with a frequency of 13,000 lines/mm were successfully fabricated.