氮化镓注镁(Mg:GaN)的光致发光

利用低压MOCVD在蓝宝石衬底上外延生长了GaN,用离子注入法掺入Mg杂质,退火后,进行光致发光测量,观察到显著的蓝光发射和黄带发射.光谱分析给出了与注入Mg离子相关的GaN禁带中能级的精细结构,其中: 间位Mg(Mgi)能级(导带下170meV)到替位Mg(MgGa)受主能级(价带上250meV)的跃迁产生了415nm发光峰; 该能级到价带上390meV能级的跃迁,以及带有紧邻N空位的替位Mg(MgGaVN)能级(导带下310meV)到 MgGa受主能级的跃迁,均产生了438nm发光峰.另外,退火使GaN晶格结构部分恢复,再现了黄带发射.

Photoluminescence of Mg-Implanted GaN

Room temperature photoluminescence of Mg implanted GaN grown on sapphire by low pressure metalorganic chemical vapor deposition (LP MOCVD) is studied.Clear blue emission and broad yellow band are observed.The fine structure of Mg related energy levels in GaN is suggested that transition from Mg i with energy level at 170meV which is below conduction band to Mg Ga with acceptor energy level at 250meV which is above valence band is responsible for the blue emission of 415nm,and the transition from the former level to the energy level at 390meV which is above valence band,as well as the transition from the energy level of the nearest neighbor associated of a Mg Ga acceptor with a nitrogen vacancy,at 310meV which is below conduction band, to the spatially separated isolated Mg Ga acceptor energy level,are responsible for the blue emission of 438nm.Annealing partially recovered the crystalline structure,leading to the reappearance of the common yellow band.