Investigation of Deep Trap Center of AlN Grown on Si Substrate
Si基MOCVD生长AlN深陷阱中心研究

The deep trap center of AlN grown on Si substrate is investigated with PL spectr a and Raman spectra.Three deep trap centers E t1, E t2 and E t3 are found at 2.61,3.10,and 2.11eV above E v,respectively. E t1 is induced by superposition of the peak of O impurities and peak o f N vacancies (or interstitial Al atoms).Because of the high growth temperature, Si atoms diffuse into the AlN layer and take the places of Al atoms and Si-N bo nds are formed.After annealing,when the density of Si is higher than a critical one,some Si atoms take the places of N atoms and Al-Si bonds are formed. E t2 is induced by Si-N bonds and E t3 by Al-Si bonds.It is also fo und that E t1 and E t2,the deep trap centers,are stable even a fter high temperature annealing for several hours.