Investigation of the Characteristics of the Boron Doped MnO Films Deposited by Spray Pyrolysis Method

Boron doped MnO films were prepared by spray pyrolysis technique at 375°C substrate temperature, which is a low cost and large area technique to be well-suited for the manufacture of solar cells, using boric acid (H₃BO₃) as dopant source, and their properties were investigated as a function of doping concentration. Boron doping was achieved by adding 0.1 M, 0.2 M, 0.3 M, and 0.4 M H₃BO₃ to the starting solution. X-ray analysis showed that the films were polycrystalline fitting well with a cubic structure and have preferred orientation in (111), (220) and (311) directions. Optical band gap of the undoped and B-doped MnO films were found to vary from 2.25 to 2.54 eV. The changes observed in the energy band gap and structural properties of the films related to the boric acid concentration are discussed in detail.