*L. Jay Guo, Xi Chen, Kaito Yamada, Sean Ahn, Youngjae Shin, Xing Cheng, Moonkyu Kwak, Jong Ok, The University of Michigan, Ann Arbor, MI
We proposed colored solar cells that can fit its background for large area deployment of solar panels covering more surfaces. Our earlier work is based on a-Si solar cell integrated with thin-film optical resonators. Later we developed more efficient colored solar cells by integrating a thin-film based reflective color filter with high-efficiency Si solar cells. In another topic, we show that deep subwavelength structures can be patterned by near-UV light without resorting to the expensive stepper tools used in semiconductor industry. The principle is based on Plasmonic lithography, which has capable of high resolution beyond diffraction limit. But all previously attempts suffer from issues such as shallow pattern depth and non-uniformity even over small exposure area, which seriously limits the application of the technology. Using specially designed thin film stack structures, we developed plasmonic waveguide lithography that addressed the above issues and can be further extended to continuous patterning. This approach provides a more sustainable route for nanostructure fabrication that is cost effective and avoid the use of sophisticated instruments.