Lithography-Free Nanofilm Color Filters Composed of CMOS-Compatible Materials

• Published in: IEEE photonics technology letters Vol. 33; no. 13; pp. 672 - 675
• Main Authors: Qian, Wenchao, Wang, Yilin, Zhang, Song, Song, Maowen, Zou, Yi, Xu, Ting
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-07-2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: CMOS; Color filter; Display devices; Electric fields; Image color analysis; Nanoscale devices; Nonhomogeneous media; Performance evaluation; Plasmons; Refractive index; spectrum; thin film
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2021.3086088

Nanostructures with the ability to efficiently generate colors in visible range attract lots of attention. Current plasmonic materials-based techniques always require complicated lithographic processes, which are expensive and severely limiting the production throughput. In this letter, we experimentally demonstrate a large-area silicon-based multilayer structure for color filtering. The designed lithography-free nanofilm color filters possess high transmission (>70%) and wide-angle tolerance (up to ±30°) for both TE and TM polarizations. Our approach, featuring excellent performance together with CMOS compatible materials, steps forward towards practical applications such as image sensors and display devices.