Two-dimensional sub-200 nm pitch Si gratings with natural orthogonality

Abstract

As a standard for length and angle, two-dimensional (2D) grating reference materials can be used for performance verification and calibration of various microscopes and 2D stages. This paper proposes a 2D nanoscale reference grating manufactured by combining laser-focused atomic deposition (LFAD) and extreme ultraviolet interference lithography. The theoretical pitch of the 2D grating is 150.46 nm, which is only √2/2 times the pitch of the Cr grating manufactured by LFAD that can be traceable to the resonance transition frequency of Cr. Moreover, the angle between two periodic directions of the 2D nanograting has natural orthogonality.

Research on Tip Characterization Techniques Based on Two-Dimensional Self-Traceable Nano-Gratings

“…Based on the grating sample fabrication process described in the third section, when the mask was perfectly vertical during preparation, the spacing of the two-dimensional grating was equal to the one-dimensional self-traceable chromium grating intercept. This intercept corresponds to the radiation wavelength of the chromium atomic transition, which was √ 2/4 times the wavelength [25], resulting in P 0 = 150.46 nm. The period calculations for the three sampled profiles within the same scale were compared, and the results of the sampled profiles are as shown in Figure 8.…”