Development of GaAsBiN alloys for next generation photodiodes and solar cells.

铋(Bi)和氮(N)是V族元素，可以少量添加到传统的III-V半导体中，以改变价/导带结构，而晶格参数变化相对较小。这使得它有可能用于一系列光电设备，如光电探测器、发光二极管和太阳能电池。学生将密切参与GaAsBiN外延层的生长以及它们的光学、电学和结构特性的表征。合适的测试结构将被培养出来，学生将观察这种材料的光致发光和泄漏电流特性，最初是在室温下，然后降低到77开尔文。一个主要目标将是在这些外延层的生长过程中将缺陷和陷阱的发生降至最低。

Bismuth (Bi) and Nitrogen (N) are Group V elements that can be added in small quantities to conventional III-V semiconductors like GaAs, to vary the valence/conduction band structure with a relatively small change to the lattice parameter. This makes it potentially useful for a range of opto-electronic devices such as photodetectors, light emitting diodes and solar cells. The student will be closely involved in the growth of epitaxial layers of GaAsBiN and the characterisation of their optical, electrical and structural properties. Suitable test structures will be grown and the student will look at the photoluminescence and leakage current properties of this material, initially at room temperature but then down at 77 Kelvin. A major objective will be to minimise the occurrence by defects and traps during the growth of these epitaxial layers.