Effect Of Hydrogen Passivation On The Electronic Structure Of Ⅲ-Ⅴ Nitride Quantum Dots

The pseudohydrogen is theoretically used to passivate the surface dangling bonds of thin films and nanostructured semiconductors. As we all know, the band gap of the semiconductor nanostructure is broader than that of bulk materials due to the quantum confinement effect. In this work, the effect of hydrogen passivation on the electronic structures of nitride quantum dots are studied based on the density functional theory, We have also analyzed the difference between realhydrogen (RH) and pseudohydrogen (PH) surface passivation in detail.A model is proposed to passivate the surface atoms of AlN, GaN, InN quantum dots with zinc blende (ZB) and wurtzite (WZ) structures. Based on the density functional theory within the generalized gradient approximation approach, we have caculated the bandgaps of bare quantum dots, bulk materials, RH-passivated quantum dots and PH-passivated quantum dots, respectively. Compared the results of bandgap, we have found PH passivation would increase the band gaps of four materials. The role of RH passivation is different from the case of PH passivation. The bandgap will decrease for the wide-gap materials. Besides, we also find that the difference of the band gaps between RH-passivated quantum dots and PH-passivated quantum dots will decrease with the covalency of the semiconductors increasing. Our results will expand the tunability of the nanostructured semiconductor properties.