1. Patterning of high-aspect-ratio nanogratings using phase-locked two-beam fiber-optic interference lithography
- Author
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Liyang Chen, Zhuofei Gan, Siyi Min, Chuwei Liang, Jingxuan Cai, Wen-Di Li, Dehu Cui, and Xing Cheng
- Subjects
Materials science ,Optical fiber ,Silicon ,chemistry.chemical_element ,02 engineering and technology ,Photoresist ,Grating ,01 natural sciences ,Nanoimprint lithography ,law.invention ,Interference lithography ,Laser linewidth ,law ,Etching (microfabrication) ,0103 physical sciences ,Materials Chemistry ,Electrical and Electronic Engineering ,Instrumentation ,010302 applied physics ,business.industry ,Process Chemistry and Technology ,021001 nanoscience & nanotechnology ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Optoelectronics ,0210 nano-technology ,business - Abstract
Patterning high-aspect-ratio gratings by the phase-locked two-beam fiber-optic interference lithography (2-FOIL) is numerically and experimentally investigated in this paper. The Dill model is applied in the numerical simulation to understand the effects of an exposure dose and pattern contrast on the exposed photoresist grating profiles. Exposure experiments on the authors’ home-built 2-FOIL setup are conducted to demonstrate the suitability for manipulating the linewidth of photoresist gratings by tuning the exposure dose to achieve high aspect ratios over 6 at high pattern contrast thanks to the phase-locking mechanism. The high-aspect-ratio photoresist gratings serve as an excellent etching mask for the subsequent pattern transfer into underlying silicon substrates for high-aspect-ratio silicon gratings. Using these high-aspect-ratio silicon gratings as the nanoimprint mold, a square nanomesh is demonstrated by means of the multiple-step nanoimprint lithography. The authors’ work demonstrates that the proposed phase-locked 2-FOIL system enables high pattern contrast under long exposure duration, making it a suitable tool for fabricating high-aspect-ratio grating structures.Patterning high-aspect-ratio gratings by the phase-locked two-beam fiber-optic interference lithography (2-FOIL) is numerically and experimentally investigated in this paper. The Dill model is applied in the numerical simulation to understand the effects of an exposure dose and pattern contrast on the exposed photoresist grating profiles. Exposure experiments on the authors’ home-built 2-FOIL setup are conducted to demonstrate the suitability for manipulating the linewidth of photoresist gratings by tuning the exposure dose to achieve high aspect ratios over 6 at high pattern contrast thanks to the phase-locking mechanism. The high-aspect-ratio photoresist gratings serve as an excellent etching mask for the subsequent pattern transfer into underlying silicon substrates for high-aspect-ratio silicon gratings. Using these high-aspect-ratio silicon gratings as the nanoimprint mold, a square nanomesh is demonstrated by means of the multiple-step nanoimprint lithography. The authors’ work demonstrates that the...
- Published
- 2019
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