ZnO是优异的紫外发光和激光材料, 氮被认为是p型ZnO和MgZnO的理想受主掺杂剂, 但在较低生长温度下氮的掺入会显著破坏晶格完整性, 使氧化锌的载流子迁移率进一步下降。为了研究N的掺入对MgZnO薄膜的影响, 利用分子束外延设备在蓝宝石衬底上生长了N掺杂的ZnO和MgZnO薄膜。实验结果表明, 在其他条件完全相同的情况下, 当Mg源温度为245 ℃和255 ℃时,载流子迁移率会显著提高, 这一现象被归结为Mg—N成键抑制了氧位上N—N对的形成, 缓解了晶格的扭曲。同时当Mg源温度为275 ℃时, 能够使N掺杂ZnO薄膜中的施主浓度降低一个量级, 有利于实现p型掺杂。

ZnO is an excellent UV light-emitting and lasing materials. Nitrogen is considered to be the ideal acceptor dopant for p-type ZnO and MgZnO. However, the lattice integrity of the nitrogen-doped samples grown at the lower growth temperature is remarkably influenced, which results in a further decrease in the carrier mobility of the zinc oxide. In order to study the effect of N doped MgZnO films, N-doped ZnO and MgZnO thin films were grown on sapphire substrate by molecular beam epitaxy. Comparing the difference between N doped MgZnO and ZnO, the experimental results show that the carrier mobility increased significantly when the Mg source temperature was 245 ℃ and 255 ℃, which is attributed to the fact that Mg—N bonding alleviates the formation of N—N pairs on the oxygen sites and relieves the lattice distortion. At the same time, the donor concentration in N-doped ZnO thin films can be reduced by one order of magnitude when the Mg source temperature is 275 ℃, which is advantageous for p-type doping.