Photonic crystal silicon based structures for thin film solar cell

• Published in: 2009 Asia Communications and Photonics conference and Exhibition (ACP) Vol. 2009-Supplement; pp. 1 - 7
• Main Authors: Drouard, E., Park, Y., El Daif, O., Letartre, X., Viktorovitch, P., Fave, A., Kaminski, A., Lemiti, M., Seassal, C.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01-11-2009
• Subjects: Absorption; Amorphous silicon; Crystalline materials; Lighting control; Optical control; Optical coupling; Optical polarization; Photonic crystals; Photovoltaic; Photovoltaic cells; Semiconductor thin films; Thin film devices and applications
• ISSN: 2162-108X; 2162-1098

A design is proposed to significantly increase the absorption of a thin layer of absorbing material such as amorphous silicon. This is achieved by patterning a one-dimensional photonic crystal (1DPC) in this layer. Indeed, by coupling the incident light into slow Bloch modes of the 1DPC, we can control the photon lifetime and then, enhance the absorption integrated over the whole solar spectrum. Optimal parameters of the 1DPC maximize the integrated absorption in the wavelength range of interest, up to 45% in both S and P polarization states instead of 33% for the unpatterned, 100 nm thick amorphous silicon layer. Moreover, the absorption is tolerant with respect to fabrication errors, and remains relatively stable if the angle of incidence is changed.