Photoluminescence study based prediction on visible luminescence from n-Zno/p-GaAs heterojunction

Semiconductor heterojunction is an alternate approach in device fabrication where p-n homojunction could not be made possible due to nonavailability of a particular type of doping with required stability and carrier concentration as a fall out of self-compensation arising out of the non-stoichiometry. ZnO is one such material. In the present investigation a heterojunction of n-ZnO with p-GaAs has been made to investigate the light emission properties of the heterojunction. From the room temperature photoluminescence spectrum of the heterojunction, efforts have been made to predict the colour of the light emitted from it based on spectral response. It is observed that n-ZnO/p-GaAs heterojunction could emit in the purplish red region though the band gap of the constituent materials do not have the requisite band gap for such an emission. The color temperature is found to be less than 1000 K.