Self-Diffusion in beta-Ga2O3 Single Crystals

β-Ga2O3 单晶中的自扩散

• 批准号: 433461542
• 负责人: Professor Dr. Harald Schmidt
• 金额: --
• 依托单位: Institut für Metallurgie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/433461542?language=en
• 关键词: Self; Diffusion; beta; Ga2O3; Single

Gallium oxide (beta-Ga2O3) is an ultra-wide bandgap semiconductor with increasing importance in various technological fields because of its multifunctional use in diverse applications (power electronics, gas sensor, photo detector, transparent conducting oxide etc.). The electrical and optical properties of beta-Ga2O3 depend critically on the concentration, charge state and migration of native point defects (oxygen vacancies, gallium interstitials, gallium vacancies etc.). Self-diffusion experiments can give information on the nature of native defects and their mobility in the material. However, up to now there are no self-diffusion studies available in literature.The aim of the present proposal is the systematic experimental determination of oxygen and gallium tracer diffusivities in beta-Ga2O3 single crystals as a function of temperature. This work will be carried out with secondary ion mass spectrometry (SIMS). Oxygen tracer diffusion experiments will be achieved by isotope exchange using 18O2 as a gaseous tracer source. In order to investigate the Ga diffusion, Al will be used as a substitute tracer. From the results, activation energies and pre-exponential factors will be derived. The diffusion experiments will be done as a function of oxygen partial pressure at different temperatures. By consideration of fundamental defect reactions and comparison to theoretical work as given in literature, certain model assumptions on dominating defect structures and their kinetics can be proven or discarded. The results will also help to understand the oxygen partial pressure dependence of electronic conductivity and the contribution of ion conductivity at moderate temperatures below 900 K.

氧化甘露（β-GA2O3）是一种超宽的带隙半导体，由于其在各种应用中的多功能用途（电力电子，气体传感器，光电检测器，透明导电氧化物等），因此在各种技术领域的重要性越来越重要。 β-GA2O3的电气和光学特性急剧取决于天然点缺陷的浓度，电荷状态和迁移（氧气空位，胆汁间隙，胆汁空位等）。自扩散实验可以提供有关本地缺陷性质及其在材料中的流动性的信息。但是，到目前为止，文献中尚无自扩散研究。本提案的目的是系统的实验确定β-GA2O3单晶的氧气和甘油示踪剂扩散作为温度的函数。这项工作将使用次级离子质谱法（SIMS）进行。使用18O2作为气态示踪剂来源，将通过同位素交换来实现氧气示踪剂扩散实验。为了研究GA扩散，AL将用作替代示踪剂。从结果中，将得出激活能和指数前因子。扩散实验将作为在不同温度下的氧局部压力的函数进行。通过考虑基本缺陷的反应以及与文献中给出的理论工作的比较，可以证明或丢弃有关缺陷结构及其动力学的某些模型假设。结果还将有助于理解电子电导率的氧部分压力依赖性以及在900 K以下的中等温度下离子电导率的贡献。