Band anticrossing in dilute nitrides
Band anticrossing in dilute nitrides
复制标题
稀氮化物中的能带反交叉
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
E. Haller
中科院分区：
文献类型：
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作者：
W. Shan;K. Yu;W. Walukiewicz;Junqiao Wu;J. Ager;E. Haller
将III-V族化合物与少量氮合金化导致所得稀氮化物合金中的基本带隙能量的急剧降低。这种效应源于扩展导带态和局域N态之间的反交叉相互作用。这种相互作用将导带分裂成两个非抛物线的子带。下导子带边缘的向下移动是N诱导的基本带隙能量降低的原因。导带结构的变化导致电子有效质量的显著增加和电子迁移率的降低，并导致掺杂VI族施主的GaInNAs的最大掺杂水平的大幅度提高。此外，IV族和VI族供体的电激活中的显著不对称性可归因于通过形成最近邻IV族供体氮对的相互钝化过程。
Alloying III-V compounds with small amounts of nitrogen leads to dramatic reduction of the fundamental band-gap energy in the resulting dilute nitride alloys. The effect originates from an anti-crossing interaction between the extended conduction-band states and localized N states. The interaction splits the conduction band into two nonparabolic subbands. The downward shift of the lower conduction subband edge is responsible for the N-induced reduction of the fundamental band-gap energy. The changes in the conduction band structure result in significant increase in electron effective mass and decrease in the electron mobility, and lead to a large enhance of the maximum doping level in GaInNAs doped with group VI donors. In addition, a striking asymmetry in the electrical activation of group IV and group VI donors can be attributed to mutual passivation process through formation of the nearest neighbor group-IV donor nitrogen pairs.