Application of Bayesian optimization for improved passivation performance in TiO<sub> x </sub>/SiO<sub> y </sub>/c-Si heterostructure by hydrogen plasma treatment
Shinsuke Miyagawa, Kazuhiro Gotoh, Kentaro Kutsukake, Yasuyoshi Kurokawa, Noritaka Usami
Abstract
Abstract We applied hydrogen plasma treatment (HPT) on a titanium oxide/silicon oxide/crystalline silicon heterostructure to improve the passivation performance for high-efficiency silicon heterojunction solar cells. To accelerate the time-intensive process optimization of many parameters, we applied Bayesian optimization (BO). Consequently, the optimization of six process parameters of HPT was achieved by BO of only 15 cycles and 10 initial random experiments. Furthermore, the effective carrier lifetime after HPT on the optimized experimental conditions became three times higher compared with that before HPT, which certifies that BO is useful for accelerating optimization of the practical process conditions in multidimensional parameter space.