Metallic Antireflection Structures Made from Silver Ink by a Liquid Transfer Imprint Lithography Technique

摘要

Solar power can become a major source of energy that is beneficial to the environment. However, the front surfaces of solar cells have a reflectance greater than 30%, resulting in low energy-conversion efficiencies. The light-absorption performance of solar cells can be improved by using antireflection structures (ARSs), which are effective in ensuring efficient absorption of light. Liquid transfer imprint lithography (LTIL) is a promising method for producing thin films under atmospheric conditions. In addition, it is possible to obtain thin and uniform films using a roller regardless of the viscosity of the liquid. We succeeded in forming metallic ARSs by using silver ink and a LTIL process. Metallic ARSs without a residual layer were produced at a roll pressure of 40 MPa in the first LTIL cycle, thereby improving its reflectance. Furthermore, reflection from the metallic ARSs with a high aspect ratio showed intense plasmon peaks around a wavelength of 560 nm, exhibiting a green color on the surface. Consequently, our process is suitable for fabricating metallic ARSs by using high-viscosity materials such as silver ink.