Perovskite solar cells (PVSCs) have continued to evolve greatly to become more appealing as a way to harness energy. However, they still have low efficiency, instability, and a long annealing time that holds them back from low-cost manufacturing. PVSC uses metal oxides as charge transport layers. These oxides must be formed into the desired crystallinity and the current method for this transition is hot plate annealing. A large drawback with this process is that the hot plates heat all the deposited layers simultaneously, which is destructive to the flexible substrates and perovskite active layer.
The novel invention utilizes a photonic treating technology, LED light, instead of the hot plate method. The LED light has a highly selective band of wavelength which can accomplish the layer-specific treatment for SnO2 and NiOx (metal oxides) without causing damage to the underlying films. Additionally, because LEDs can have a response time as low as 20 nanoseconds, they do not take a lot of time to “heat up” as other lamps do. This allows for precise control for pulsing the light.
• Localized annealing. (does not harm the surrounding layers) • High efficiency and high stability. (higher energy conversion) • Virtually no wait-time. (allows for rapid printing) • LEDs are low cost and highly selective