Si表面吸附GaN的第一性原理研究

First-principle Study on Adsorption of GaN on Surface of Si

为了更好地了解Si表面对GaN的吸附,利用基于密度泛函理论的第一性原理平面波赝势方法,计算了Si(100)和Si(111)弛豫表面分别吸附GaN的电子结构、吸附能大小以及其态密度图。计算结果表明,相对于Si(111)表面,Si(100)表面更容易吸附GaN,在同等实验条件下,在Si(100)表面应更容易沉积GaN薄膜。采用ECR-MOPECVD工艺,于低温下在Si(100)衬底上沉积得到了GaN薄膜,XRD谱图表明该薄膜是一种晶体结构和无定形结构的混合结构。

In order to know the adsorption between the surface of Si and GaN, the electronic structures,adsorption energy and DOS（density of states） of GaN on surface of Si （100） and Si （111） are calculated with first-principle using plane-wave pseudo potentials method based on the density functional theory. Results show that surface of Si （100） can adsorb more GaN molecular than surface of Si （111）. GaN film can be deposited more easily on the surface of Si （100）. On the other hand, GaN film is deposited on the surface of Si （100） by ECR-MOPECVD at low temperature.