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Ⅲ-Ⅴ族氮化物宽禁带半导体材料体系中,普通方法生长的p型外延层电导率一般都很低,成为了制约器件性能提高的瓶颈。在p-AlxGa1-xN材料中,Mg受主的激活能较大,并且随Al组份增加而增大。通过在p-AlxGa1-xN材料生长过程中引入三甲基铟(TMIn),发现能有效地降低AlxGa1-xN材料中受主态的激活能。为研究不同In气氛下生长的p-AlxGa1-xN材料的性质,在使用相同二茂基镁(CP2Mg)的情况下,改变TMIn流量,生长了A,B,C和D四块样品。X射线衍射(XRD)组份分析表明:在1100℃下生长AlxGa1-xN外延层时,In的引入不会影响晶体组份。利用变温霍尔(Hall)测试研究了p-AlxGa1-xN材料中受主的激活能,结果表明:In气氛下生长的外延层相比无In气氛下生长的外延层,受主激活能明显降低,电导率显著提高。采用这种方法改进深紫外发光二极管(LED)的p-AlxGa1-xN层后,LED器件性能明显提高。
In the III-V nitride wide band gap semiconductor material system, the conductivity of the p-type epitaxial layer grown by the conventional method is generally low, which becomes a bottleneck for improving the performance of the device. In the p-AlxGa1-xN material, the activation energy of Mg acceptor is larger, and increases with the increase of Al composition. The introduction of trimethyl indium (TMIn) during the growth of p-AlxGa1-xN material has been found to reduce the activation energy of the host AlxGa1-xN material effectively. In order to study the properties of p-AlxGa1-xN materials grown under different In atmospheres, four samples of A, B, C and D were grown with the same flow rate of TMIn with the same Mg (CP2Mg) X-ray diffraction (XRD) analysis showed that the introduction of In did not affect the crystal composition when the AlxGa1-xN epitaxial layer was grown at 1100 ℃. The activation energy of the acceptor in the p-AlxGa1-xN material was investigated by Hall test. The results show that the epitaxial layer grown in In atmosphere has a significantly lower acceptor activation energy compared with the epitaxial layer grown without In atmosphere. , The conductivity increased significantly. With this method to improve the deep UV LED (p-AlxGa1-xN layer, LED device performance improved significantly.