[10a-PA4-1~10] 9.1 Dielectrics, ferroelectrics

[10a-PA4-6] Physical Properties Evaluation of Piezoelectric Nitride Mg,Nb Codoped AlN by First-principles Calculation

〇Yuto Mori¹, Kenji Hirata², Sri Ayu Anggraini², Morito Akiyama², Masato Uehara^2,1, Hiroshi Yamada^2,1 (1.Kyushu Univ., 2.AIST)

Keywords:Piezoelectric material, Nitride, First-principles calculation

The structural and physical properties of Mg_xNb_yAl_1-x-yN (x/y = 1) were investigated by the First-principles calculations for understanding the mechanism on the enhancement of the piezoelectric response in present work. The calculated elastic constant C₃₃ of MgNbAlN is lower than that of AlN and the piezoelectric constant d₃₃ is higher than that of AlN. Furthermore, the reduction of the elastic constant C₃₃ is considered to be due to the phase transition from the wurtzite phase to the metastable BN-type hexagonal phase in analogy with the case of Sc doped AlN.