Preidel, V.; Lockau, D.; Sontheimer, T.; Back, F.; Rudigier-Voigt, E.; Rech, B.; Becker, C.: Analysis of absorption enhancement in tailor-made periodic polycrystalline silicon microarrays. Physica Status Solidi - Rapid Research Letters 7 (2013), p. 1045–1049
We present a design study of 3D photonic poly-Si micro-architectures on 2 µm periodically textured glass substrates for application as absorber layers in crystalline Si thin-film solar cells. Different arrays of microholes and microcones were fabricated in a low-cost process, by combining high rate electron beam evaporation, nanoimprint technology and self-organized solid phase crystallization. Two promising designs exhibiting strong absorption enhancement were identified by optical analysis. High angular acceptance and calculated maximum achievable photocurrent density of 27.6 mA/cm2 for an effective Si thickness of 1.1 µm highlight the potential of these microarchitectures as broadband absorbers in poly-crystalline Si thin-film solar cells.