Abstract: Embodiments in accordance with the present invention relate to the fabrication of thin (>1 ?m) polycrystalline, nanocrystalline, or amorphous silicon films on a substrate. Particular embodiments utilize liquid sources of silane, including but not limited to cyclohexasilane (CHS), cyclopentasilane (CPS) or related derivatives of these compounds. In one embodiment, the silane is applied in liquid form contained by the use of a series of raised walls. Subsequent polymerization results in the material being a solid form. In other embodiments, the silane is applied as a liquid which is then frozen, with subsequent localized melting allowing polymerization to convert the material into a stable solid form. Embodiments of the present invention are particularly suited for forming thick (>10 ?m) silicon films needed to achieve light absorption efficiencies deemed acceptable for thin film photovoltaic devices.

Abstract: Embodiments of the present invention relate to fabricating low cost polysilicon solar cell on flexible substrates using inkjet printing. Particular embodiments form polycrystalline or microcrystalline silicon solar cells on substrates utilizing liquid silane, by employing inkjet printing or other low cost commercial printing techniques including but not limited to screen printing, roller coating, gravure coating, curtain coating, spray coating and others. Specific embodiments employ silanes such as cyclopentasilane (C5H10) or cyclohexasilane (C6H12), which are liquids at room temperature but undergo a ring opening chemical reaction upon exposure to radiation of a wavelength of ultraviolet (UV) or shorter. . Opening of the rings of the liquid silane converts it into a polymerized material comprising saturated and unsaturated silicon chains of varied length. Heating to approximately 250-400° C. converts these materials into a hydrogenated amorphous silicon film.