NOVELTY - The method involves providing a polymeric substrate (12) e.g. polyimide substrate, with upper operating temperature. A photovoltaic precursor e.g. p-type photovoltaic layer (16), is deposited directly or indirectly on the substrate, where photovoltaic efficiency of the precursor is less than 1 percentage. The precursor is exposed to a predominately infrared light to thermally convert the precursor into a crystalline photovoltaic material having the photovoltaic efficiency greater than 1 percentage without causing the substrate to exceed the substrate upper operating temperature.    USE - Method for manufacturing a photovoltaic device such as thin film solar cells (all claimed), for fabricating a hand-held electronic device such as cell phone, laptop and camera, and fabrics such as clothes, backpacks and temporary shelters for windows, and for use on large sheets of a building and a vehicle.    ADVANTAGE - The method enables permitting the usage of polymeric substrates to prevent damage to the device by energy or heat and reducing the weight of the photovoltaic device and complexity of techniques for crystallizing photovoltaic precursors. The method enables providing moderately efficient solar cells with greater than 5 percentage efficiency at extremely low manufacturing costs. The photovoltaic precursor is exposed to energy of sufficiently high intensity and sufficiently low duration, thus achieving grain growth without materially thermally affecting the underlying substrate. The method enables improving the manufacturing process of high efficiency photovoltaics and improving material quality and grain size of photovoltaic precursor supported by the substrate.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for the following:    (1) a photovoltaic device comprising a flexible substrate    (2) a system for forming a photovoltaic device comprising a web.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of a fabricated photovoltaic device.    Photovoltaic device (10)    Polymeric substrate (12)    Optional electrode layer (14)    P-type photovoltaic layer (16)    N-type photovoltaic layer (18)    Optional front electrode layer (19)