Al掺杂纤锌矿GaN电子结构第一性原理计算

The Research on First-principles Electronic Structure for Al-doped Wurtzite GaN

采用第一性原理方法,在LMTO-MBJ框架下精确的计算Ga N和Al N的电子结构,计算结果与实验值一致.应用CPA的方法计算任意量的Al掺杂Ga N合金的电子结构,理论计算表明,Ga N的带隙宽度随Al掺杂浓度x的增大而增大,而且满足关系式Eg=3.43+2.3x(0≤x≤0.65),Eg=2.45+3.7x(0.65≤x≤1).计算可为氮化物半导体Ga N、Al N及其三元合金化合物Ga1-xAlxN的实验研究提供理论依据.

Using first - principles approach, the band gap of the wurtzite GaN, A1N and band gap of the ternary alloy Ga1-xAlxN are studied, where the modified Becke -Johnson （MBJ） semi -local exchange is used to accurately determine the band gap, and the coherent potential approximation （CPA） is applied to deal with confi gurational average for the ternary alloys. The band gap of Ga1-x AlxN increasing with the concentration of A1 are found. The calculated band gaps the ternary alloy Gal_~ AlxN satisfied the relationship between Eg = 3.43 ＋ 2.3x（0 ≤x ≤0.65 ）, Eg = 2. 45 ＋ 3.7x （0. 65 ≤x ≤ 1 ）. These theoretical prediction will he useful in the design and application of Ga1-x AlxN device.