PROGRESS IN THIN FILM ENCAPSULATION TECHNOLOGY ADVANCED MOISTURE BARRIERS FILMS
Drs. E. Ryabova, A. Skumanich, M. Shkolnikov | PV SEC 26th International Conference Proceedings, September 2011, Hamburg, Germany
Highly scalable disruptive thin film deposition technology is developed and validated based on a modified sol-gel method in response to PV-industry quest for the high quality-low cost methods of fabricating PV-cell structures. This “liquid” based approach is envisioned to replace currently used encapsulants to enable high throughput conveyer type processing of PV-cells with enhanced performance due to the outstanding purity, uniformity and extended light management capability of this method. Solution Derived Nanocomposite (SDN®) technology offers an unmatched potential for moisture barrier materials design and engineering in terms of composition and microstructure without using cost prohibitive solutions. Wide variety of layer compounds can be formed, free from residual byproduct intoxication of the cell. SDN® encapsulating technology demonstrated the necessary capability to produce protective moisture barrier layer on top of TFPV-structure without compromising its’ as-produced power conversion efficiency. This layer can minimize environmental impact and weathering-caused TFPV-cell performance deterioration. SDN® films satisfy the requirements in regard to the damp heat (85/85) test and UV resistance verification, and are lower cost.
LOW COST HIGH PERFORMANCE TCO FILMS- PROCESS INTEGRATION AND RELIABILITY
Drs. E. Ryabova, A. Skumanich, and M. Shkolnikov | IEEE 37th PV SC International Conference Proceedings, July 2011, Seattle, WA, USA
The importance of advances in solar cells fabrication has been stressed lately by multiple FiT cuts and abrupt reduction in many other subsidies across the world. The adoption of photovoltaics as a replacement for the fossil fuels however is driven by the threatening to the ecological stability of the planet and has to do with the very existence of humankind. Thin Film Photovoltaics (TFPV) hold a promise to become a contrivance of choice if they will be able to raise numbers for power conversion efficiency complemented by reasonable stability and reliability data. TFPV cell is assembled of several critical layers sandwiched between electrodes, at least one of which has to be transparent. Transparent Conductive Oxides (TCO) play a critical role in PV-cell structure providing incoming passage for the light and outgoing passage for the charge carriers created as a result of conversion. High optical transparency and electrical conductivity are required for the enhanced solar cell performance. Non- defective interface with the under laying film stack is vital for the minimization of loses. Moreover those parameters have to be stable over the extended period of time in order to be practical for the PV-module field installation. Highly efficient technologies (in terms of material cost and utilization rate as well as low capital expenditure and energy consumption) are in demand to build a solar device of required quality and stability at non-prohibitive cost. Non-vacuum low impact technology is developed based on a liquid processing that can provide thin films of excellent purity and precision stoichiometry as well as accommodate conveyer based cells’ manufacturing. Optical, electrical and microstructural properties of these films on glass are tested; as deposited and after exposure to several durability testing methods. Excellent stability is verified in accordance with IEC 61730 and IEC 61215 standard procedures.