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  1. Rapid advancements within photovoltaics realm necessitates swift fabrication of the modules using cheap materials through cost effective manufacturing processes to achieve short cost payback time. Photovoltaics manufacturing includes chemical processing of the materials followed by thermal annealing. Yet, long-term annealing of the materials using high temperature furnaces have remained the prevalent post-processing approach in industry which necessitates alternative methods to achieve high performance modules through rapid and economical processes. Intense pulse light (IPL) has been successfully applied as a promising rapid post-process annealing for various thin film photovoltaics, particularly to process the organic-inorganic perovskite solar cell (PSC) layers. In this paper, several results pertinent to the application of IPL on perovskite and SnO2 electron transport thin films are presented and the role of IPL on rapid thermal annealing (RTA) is explained. We show that swift fabrication of PSCs through IPL can result in efficiencies exceeding 16% when the Perovskite film is annealed with aid of CH2I2 alkyl halide additive in the ambient with 60% relative humidity. In addition, the synergy of IPL-alkyl halide interaction for other perovskite chemistries is introduced. We show that achieving to PSCs exceeding 12% efficiency was possible when the perovskite and SnO2 ETL was annealed sequentiallymore »through IPL.« less
  2. Aerosol Jet Printing is a novel micron-scale printing technology capable of handling a variety of materials due to a large print material viscosity range and high substrate standoff distance of 3-5 mm. To finalize the properties of printed materials, a form of post-processing is often required. A current widely applicable post-processing technique exists in traditional oven curing. However, oven curing greatly restricts the viable substrates as well as curing time. Intense Pulsed Light (IPL) offers the chance to greatly expand this substrate variety and decrease curing time. However, limited models currently exist to relate the finished material properties to the unique settings of current IPL technology. In this paper, an experiment is developed through a General Full Factorial Design of Experiments (DOE) model to characterize conductivity of Ag ink using IPL as a post processing technique. This is conducted through Novacentrix Ag ink (JSA426) by 3x3 mm Van der Pauw sensor pads cured using IPL. Sample pads were generated in triplicate over a range of Energy Levels, Counts and Durations for IPL and the resulting conductivity measured. The collected conductivity data was then analyzed using ANOVA to determine the significant interactions. From this, a regression model is developed to predictmore »the conductivity for any Energy-Count-Duration value. The methods employed are applicable to any post-processing technique, and further optimization of the model is proposed for future work.« less
  3. The organic metal halide perovskite material is capable of high throughput manufacturing via traditional deposition processes used in roll-to-roll, yet thermal annealing post deposition may require long ovens. We report rapid annealed perovskite thin films using intense pulsed light (IPL) to initiate a radiative thermal response that is enabled by an alkyl halide additive that collectively improves the performance of a device processed in an ambient environment from a baseline of 10 to 16.5% efficiency. Previous reports on CH 3 NH 3 PbI 3 perovskite films using IPL processing achieved functional devices in milli-second time scales and are promising for high throughput manufacturing processes under ambient conditions. In this study, we found that the addition of diiodomethane (CH 2 I 2 ) as an additive to the methylammonium iodide (MAI)/lead iodide (PbI 2 ) precursor ink chemistry and subsequent IPL thermal annealing are inter-dependent. The concentration of CH 2 I 2 and IPL processing parameters have a direct effect on the surface morphology of the films and performance within a perovskite solar cell (PSC). The CH 2 I 2 dissociates under exposure to ultraviolet (UV) radiation from the IPL source liberating iodine ions in the film, influencing the perovskite formationmore »and reducing the defect states. We anticipate that these results can be utilized to further develop different ink formulations using alkyl halides for the IPL technique to improve the performance of perovskite solar cells processed in ambient conditions.« less