Ways to increase the efficiency of solar cells with extremely thin absorption layers

The effect of design parameters, electrical properties, and technological modes of formation on the efficiency of the photoelectrical conversion of solar cells with extremely thin absorbing layers based on the SnO2:F/TiO2/In2S3/In x Pb1 − x S/CuSCN is investigated. It is shown that both a decrease in resistance due to an increase in roughness and a decrease in the average grain size of the TiO2 films is attained with deposition using the sol-gel method under conditions of increased humidity. The use of Ni as the contact metal to a planarizing CuSCN layer provides the reduced value of the transient resistance. The optimization of the sequential resistance of the TiO2 film and contact resistance to the CuSCN layer provided an increase in the efficiency of photoelectric converters by a factor of more than four. The structures of solar cells formed in optimal technological modes showed the following characteristics: J sc = 9 mA/cm2, U oc = 720 mV, and they had an efficiency of 2.9%.