Crystalline Antimony Selenide Thin Films for Optoelectronics through Photonic Curing.

Thermal annealing is the most common postdeposition technique used to crystallize antimony selenide (SbSe) thin films. However, due to slow processing speeds and a high energy cost, it is incompatible with the upscaling and commercialization of SbSe for future photovoltaics. Herein, for the first time, a fast-annealing technique that uses millisecond light pulses to deliver energy to the sample is adapted to cure thermally evaporated SbSe films. This study demonstrates how photonic curing (PC) conditions affect the outcome of SbSe phase conversion from amorphous to crystalline by evaluating the films' crystalline, morphological, and optical properties. We show that SbSe is readily converted under a variety of different conditions, but the zone where suitable films for optoelectronic applications are obtained is a small region of the parameter space. SbSe annealing with short pulses (<3 ms) shows significant damage to the sample, while using longer pulses (>5 ms) and a 4-5 J cm radiant energy produces (211)- and (221)-oriented crystalline SbSe with minimal to no damage to the sample. A proof-of-concept photonically cured SbSe photovoltaic device is demonstrated. PC is a promising annealing method for large-area, high-throughput annealing of SbSe with various potential applications in SbSe photovoltaics.