Structural and optical properties of Al1-xInxN epilayers on GaN template grown by metalorganic chemical vapor deposition

This paper reports that Al1 xInxN epilayers were grown on GaN template by metalorganic chemical vapor de-position with an In content of 7%-20%. X-ray diffraction results indicate that all these Al1 xInxN epilayers have a relatively low density of threading dislocations. Rutherford backscattering/channeling measurements provide the exact compositional information and show that a gradual variation in composition of the Al1 xInxN epilayer happens along the growth direction. The experimental results of optical reflection clearly show the bandgap energies of Al1 xInxN epilayers. A bowing parameter of 6.5 eV is obtained from the compositional dependence of the energy gap. The cathodoluminescence peak energy of the Al1 xInxN epilayer is much lower than its bandgap, indicating a relatively large Stokes shift in the Al1 xInxN sample.     

基于贝叶斯算法的CPU散热片结构自动优化

本文基于数值模拟、结构设计、优化设计以及贝叶斯优化算法提出一种针对散热片结构的自动优化框架，并对CPU正弦式散热片的振幅、周期和高度进行结构优化。结果表明，优化后的正弦式散热片与平板式散热片和初始正弦式散热片相比，表面平均努塞尔数提高了195%，表面最高温度降低了6.51?C。分析了优化前后正弦散热片场协同角的变化，进一步证实了流场和温度场协同性能对散热的本质影响。