zinc oxide (ZnO)
Zinc oxide (ZnO) has so far not been very suitable as a semiconductor material because p- doping causes problems and zinc oxide is difficult to dope with foreign atoms. It is used in electronics and photovoltaics, for example in photoresistors and as transparent conductive oxides ( TCO) in solar cells, but in these and similar applications as a conductor or light-dependent material.
Recent research results show that the problems with p-doping can be solved and zinc oxide could thus replace some semiconductor materials. Blue light-emitting diodes (LEDs), which have so far been made of gallium nitride ( GaN), or as transparent contact fingers of thin-film solar cells are being considered.