Automated Fabrication of Perovskite Photovoltaics Using Inkjet Printing and Intense Pulse Light Annealing

Abstract

The rapid chemistry and processing development along with exploring underlying fundamentals [1,2] have increased the performance of perovskite solar cells (PSCs) to over 25%, [3] making them a potential candidate for nextgeneration photovoltaics (PVs). PSCs consist of a photoabsorber film sandwiched between n-type and p-type charge transport films, [4] all shown to be solution processable and thus, fabricable using scalable depositions such as slot die, [5,6] gravure, [7] spray, [8] and inkjet-printing systems [9,10] through automated manufacturing. The deposition of thin films from solutions has been shown for the SnO 2 electron transport layer (ETL), perovskite, and carbon electrodes. After deposition, these layers should undergo drying and possibly an annealing step; thus, the production of PSCs is suitable for automated manufacturing.To realize automated fabrication of PSCs with required control of the printing and IPL annealing processes, we integrated these processes into the "NeXus," a custom-designed system with robotics and motion control capabilities. The NeXus is a novel instrument for flexible multiscale manufacturing, implementing precision robotic assembly, additive manufacturing, and multiscale integration of miniature devices and systems. In addition to a commercial IPL annealing subsystem from Xenon Corporation, USA, the NeXus includes a deposition subsystem, a Pico Pulse Inkjet printhead from Nordson Corporation, USA. Samples move between these subsystems with the help of a custom 6 degree-of-freedom (DOF) robotic positioner, allowing not only fast transport of the samples between the processing tools, but also precise motion control during printing. The NeXus also integrates other manufacturing techniques, such as a dual-head fused deposition modeling (FDM) 3D printing, aerosol jetting, and microassembly. [11][12][13] Furthermore, a novel bonding process has been developed utilizing an ultrasonic vibration technique to embed metal wire in a polymer. [14,15] Slot-die coating is the most studied method for versatile and low-cost scalable deposition of thin-film PSCs, [6,16,17] whereas inkjet printing allows for the deposition of extremely high-resolution features with desired patterns. Inkjet-printing systems utilize thermal or piezoelectric drop-on-demand (DOD) technologies, where the latter produces more uniform size droplets and enables better distribution as a result of rapid

Recrystallized Perovskite Thin Film via Intense Pulse Light Sintering for Vertical Gradient Band Gap Perovskite Solar Cells

“…Nevertheless, the results from both energy balance and SEM analyses indicate that the temperature of the perovskite films under IPL irradiation exceeds 250 °C to totally fuse the perovskite. Therefore, the flash-induced temperature in the thin film can go beyond the melting temperature of perovskite and reduce to room temperature quickly within milliseconds, as indicated in the literature . This short but large temperature pulse given by IPL flash thus provides a fast melting/recrystallization mechanism to sinter MAPbI 3 and MAPbBr 3 without thermal degradation …”

“…Therefore, the flash-induced temperature in the thin film can go beyond the melting temperature of perovskite and reduce to room temperature quickly within milliseconds, as indicated in the literature. 34 This short but large temperature pulse given by IPL flash thus provides a fast melting/recrystallization mechanism to sinter MAPbI 3 and MAPbBr 3 without thermal degradation. 35 To achieve maximum sintering efficiency, MAPbBr 3 QDs are deposited on the MAPbI 3 film (Figure S3).…”

Recent Patterning Methods for Halide Perovskite Nanoparticles

“…Patterned perovskite films were fabricated using the PIJ method. [112] Despite the various inkjet printing methods, DOD methods of inkjet printing are promising for research into perovskite inkjet patterning because of the aforementioned advantages. Inkjet printing typically comprises three steps.…”

Annealing Engineering in the Growth of Perovskite Grains

“…Physical annealing primarily uses electromagnetic waves, thermal energy, ultrasonics, pressure and other physical strategies to promote precursor reactions and crystallization of perovskite [18,51,52]. Physical annealing is mostly non-direct contact annealing, which reduces the possibility of introducing impurities.…”

“…[69][70][71]. In the fabrication of perovskite, the main electromagnetic waves that have been used in the perovskite annealing process are infrared light waves, visible light, lasers and microwaves [52,72,73]. The intense pulsed light is a non-contact rapid heating method which can offer fast millisecond pulses of broad spectrum light (190-1100 nm) from xenon lamps [74].…”