以氫化物氣相磊晶成長非極性氮化鎵厚膜之研究

Abstract

本篇論文的研究重點鎖定在以氫化氣相磊晶的方式成長非極性 氮化鎵厚膜的成長與分析。有別於傳統異質磊晶的方式所成長的極性 氮化鎵材料，非極性氮化鎵材料由於有較好的內部量子發光效率與較 短的載子發光生命期，而更有本質上的優勢取代以傳統極性氮化鎵為 材料的藍光LED。 然而，成長非極性氮化鎵材料相對於一般極性面的狀況將有更多 需要克服的問題，其中包含多種物理量於in-plane 異相性的特徵， 致使成長高品質厚膜的困難度將會更為提升。因此本論文採用方法先 改變不同磊晶參數來了解非極性面成長的行為，再進一步開設光罩來 降低缺線密度與達到表面平坦度的目標。

In this research, we will focus on the growth process and analysis for how to get high quality non-polar GaN thick film by HVPE(hydride vapor phase epitaxy). Rather than the traditional technique to grow polar -GaN through hetereoepitaxy, we want to develop the non-polar GaN material having the potential to replace the original material of blue LED due to its high internal quantum efficiency and lower carriers recombination life time. However, there are many problems waited for being solved upon non-polar GaN material, such as the anisotropy characteristics of in-plane physical parameters. These problems will cause the difficulties for us to develop high quality thick film. Therefore, we tune the recipe for the first step in order to understand the surface morphology and crystal quality, and then design the mask with different fill factor to get the flat surface and lower threading dislocation density.