CONTROL OF HYDROGEN DYNAMICS IN SEMICONDUCTORS USING ELECTRONIC

本研究利用等温DLTS、IR、ESR和SR等技术研究了Si中氢-铂（H-Pt）复合缺陷的电子态和原子构型、氢在Pt杂质周围的振动和转动运动、氢向应变SiGe薄膜中的内扩散以及氢对SiGe薄膜应变弛豫的影响。1.用等温DLTS、ESR技术确定了H-Pt缺陷的对称性和结构。我们还研究了缺陷电子能级的应力依赖性，并发现缺陷在单轴应力下重新取向。我们已经确定的应力系数的能量差之间的稳定和亚稳态配置的缺陷。此外，我们还研究了电荷态对氢在Pt周围局域运动激活能的影响，发现当缺陷的电子能级未被电子占据时，氢的运动增强。2.我们实验研究了单轴应力下硅中H-Pt缺陷引起的红外吸收峰的分裂，观察到PtH缺陷在1880.7 cm ↑ <-1>[2]处的吸收峰和PtH_2缺陷在1873.1和1891.9 cm ↑ <-1>[2]处的吸收峰。在0.16 GPa应力下，分裂峰的强度比与理论预测的强度比基本一致。3.发现在Ge衬底上压应变SiGe薄膜比在Si衬底上张应变SiGe薄膜更容易发生氢原子的结合。我们还发现，在随后的热处理过程中，预掺入的氢原子增强的应变弛豫的SiGe膜的Ge。晶格应变对氢动力学的影响这一结果是第一个研究项目中所没有预料到的。

In this research, we have studied the electronic state and atomic configuration of hydrogen-platinum (H-Pt) complex defects in Si, vibrational and rotational motion of hydrogen around the Pt impurity, hydrogen indiffusion into strained SiGe films and the influence of hydrogen on the strain relaxation of SiGe films using isothermal DLTS, IR, ESR and SR techniques, and have obtained the following results.1.We have determined the symmetry and structure of H-Pt defects by isothermal DLTS, ESR techniques. We have also studied the stress dependency of defect electronic levels, and have found that defects reorient under uniaxial stress. We have determined the stress coefficient of the energy difference between stable and metastable configurations of defects. In addition, we have studied the effect of charge state on the activation energy for hydrogen local motion around Pt, and have found that hydrogen motion is enhanced when the electronic level of defects is not occupied by an electron.2.We have experimentally studied the splitting of IR absorption peaks due to H-Pt defects in Si under uniaxial stress, and have observed a peak at 1880.7 cm^<-1> of the PtH defect and peaks at 1873.1 and 1891.9 cm^<-1> of the PtH_2 defect. The intensity ratios of peaks split under a stress of 0.16 GPa are nearly equal to those predicted by theory.3.We have found that hydrogen atoms incorporate more easily into the compressively strained SiGe film on Ge substrate than the tensile strained SiGe film on Si substrate. We have also found that the pre-incorporated hydrogen atoms enhanced the strain relaxation of the SiGe film on Ge during subsequent thermal treatment. Such a result that strain of lattice affects the dynamics of hydrogen is an accomplishment beyond the expectation in the first research project.