溅射的Ti薄膜热氧化形成的TiO2薄膜与p+-Si形成的异质结的电致发光

摘要

利用磁控溅射法以不同条件在重掺硼硅片(p+-Si)上制备Ti薄膜,经过一定条件下的热氧化转化为TiO2薄膜,从而形成TiO2/p+-Si异质结.研究表明:要使TiO2/p+-Si异质结产生显著的电致发光,其中的TiO2薄膜必须呈现单一的锐钛矿相,这就要求在较低的功率下溅射获得晶粒尺寸较小的Ti薄膜.此外,TiO2的薄膜厚度需要控制在合理的范围.文中对上述结果的物理机制进行了探讨.%TiO2/p + -Si hetero structures were formed by thermal oxidation of the sputtered Ti films on heavily boron-doped silicon (p + -Si) substrates. In order to make the TiO2/p + -Si heterostructures more suitable for electroluminescence, the TiO2 films should be anastate in crystal structure. This required the precursor Ti films possess small crystal grains. Such Ti films could be sputtered at relatively low sputtering power. Moreover, the thickness of TiO2 films should be controlled in a desirable range. The related mechanisms for the abovementioned results have been discussed.