Image lithography in telluride suboxide thin film through controlling “virtual” bandgap
In this work, TeO0.7 thin films were prepared by the reactive magnetron-controlling sputtering method. Complex gray-scale patterns were successfully fabricated on TeO0.7 thin films through the laser direct writing method. The structural origin of TeO0.7 thin film was investigated for gray-scale pattern formation. It is found that multiple gray-scale levels are dependent on the “virtual” bandgap energy of TeO0.7 thin films. The bandgap energy changes lead to refractive index and reflectivity difference. Thus, gray-scale tones can be formed. By accurately controlling laser energy, various “virtual” bandgaps can be generated in TeO0.7 thin films, and colorful gray-scale levels can be formed. Experimental results indicate that TeO0.7 thin film can be used as micro/nano image writing material.
基金项目：National Natural Science Foundation of China (NSFC) (51672292, 61627826, 61137002).
Jingsong Wei：Laboratory for High Density Optical Storage, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Kui Zhang：Laboratory for High Density Optical Storage, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Long Zhang：Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, Chinae-mail: email@example.com
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Tao Wei, Jingsong Wei, Kui Zhang, and Long Zhang, "Image lithography in telluride suboxide thin film through controlling “virtual” bandgap," Photonics Research 5(1), 22-26 (2017)