In the presented work, the parameters of the new MAPD-3NM-II photodiode with the buried pixel structure manufactured by Zecotek Ph. were investigated. The following physical and electrical parameters were studied; current-voltage and capacitance-voltage characteristics, dark count rate, photon detection efficiency, gain, the temperature coefficient of breakdown voltage, breakdown voltage, and gamma-ray detection performance of photodiodes. A specialized designed readout and electronic module SPECTRIG MAPD was used to measure the parameters of the MAPD-3NM-II and a scintillation detector was based on it. The obtained results prove that the newly developed MAPD-3NM-II photodiode outperforms the former MAPD-3NM-II photodiode in most of the parameters and it can be successfully applied in space application, medicine, high-energy physicist and security. New improvements were discussed and proposed for further parameter enhancement of the MAPD photodiodes to be produced in the coming years.