Next-generation solar cells will be fabricated from low-cost and earth abundant elements, using processes that are amenable to printing on a variety of light-weight substrates. The utilization of compositionally and structurally controlled colloidal nanocrystals as building blocks for such devices fulfills these criteria. Our recent efforts in developing kesterite Cu₂ZnSnS₄ (CZTS) nanocrystals, one of the most promising materials to emerge in this area, enable the deposition of CZTS thin-films directly from a variety of solution-processed methods. Nanocrystalline thin films possess poor electronic properties, which precludes their use in solar cell devices. In order to overcome this, thermal treatment steps under an atmosphere of vaporous selenium are applied to induce large scale crystallite growth and the production of selenized CZTSSe films. This process results in a highly photoactive p-type layer. The n-type cadmium sulfide layer is also deposited from solution using chemical bath deposition. We will discuss each of these accomplishments in detail, highlighting the significant challenges that need to be overcome in order to fabricate working CZTSSe thin film solar cells.

Date Published: 7 December 2013
PDF: 5 pages
Proc. SPIE 8923, Micro/Nano Materials, Devices, and Systems, 89231K (7 December 2013); doi: 10.1117/12.2034067

Published in SPIE Proceedings Vol. 8923:
Micro/Nano Materials, Devices, and Systems
James Friend; H. Hoe Tan, Editor(s)