Grinys Tomas, Kadys Arūnas, Malinauskas Tadas, Lapukas Petras, Podlipskas Žydrūnas, Gudaitis Rimantas, Meškinis Šarūnas
Institute of Photonics and Nanotechnology, Faculty of Physics, Vilnius University, 10257, Vilnius, Lithuania.
Institute of Material Science, Kaunas University of Technology, 51423, Kaunas, Lithuania.
Sci Rep. 2025 Jul 27;15(1):27316. doi: 10.1038/s41598-025-12904-9.
In this work, we present a detailed analysis of GaN layers up to 500 nm thick, directly grown on ScO(111)/Si(111) templates using metal-organic vapor phase epitaxy. A range of measurement techniques, including X-ray diffraction, Raman spectroscopy, atomic force microscopy, cathodoluminescence, and scanning electron microscopy (SEM), were used to evaluate structural quality, strain/stress states, surface morphology, and dislocation densities. The micro-stripe formation was observed when the growth was conducted in a nitrogen atmosphere, with the stripes completely disappearing when the growth atmosphere was switched to hydrogen. The stripes were determined to be of a cubic GaN phase. The epitaxial relationships between the cubic GaN crystalline lattice and ScO, Si, and hexagonal GaN were examined in detail. Continuous, c-axis-oriented, monocrystalline GaN layers on ScO can be achieved in both [Formula: see text] and [Formula: see text] atmospheres. Prolonged nitridation processes of up to 1200 s improved the smoothness and crystallinity of the GaN layers, significantly reducing the number of extended defects. Switching the growth atmosphere from [Formula: see text] to [Formula: see text] led to reduced dislocation densities, minimized cubic GaN formation, and improved the surface morphology of the GaN layers. Our analysis shows that due to the lattice and thermal mismatch between GaN and the Si substrate, the GaN layers experience tensile strain. To manage this strain, [Formula: see text] [Formula: see text]N interlayers were inserted after 100 nm of GaN growth. This strain-engineering approach resulted in smooth, crack-free GaN epitaxial layers, demonstrating the potential for integrating GaN into silicon technology using a [Formula: see text] [Formula: see text].
在这项工作中，我们详细分析了采用金属有机气相外延法直接生长在ScO(111)/Si(111)模板上、厚度达500 nm的GaN层。使用了一系列测量技术，包括X射线衍射、拉曼光谱、原子力显微镜、阴极发光和扫描电子显微镜（SEM），来评估结构质量、应变/应力状态、表面形貌和位错密度。当在氮气气氛中进行生长时，观察到微条纹的形成，而当生长气氛切换到氢气时，条纹完全消失。确定这些条纹为立方GaN相。详细研究了立方GaN晶格与ScO、Si和六方GaN之间的外延关系。在[公式：见原文]和[公式：见原文]气氛中，都可以在ScO上实现连续的、c轴取向的单晶GaN层。长达1200 s的长时间氮化过程改善了GaN层的平滑度和结晶度，显著减少了扩展缺陷的数量。将生长气氛从[公式：见原文]切换到[公式：见原文]导致位错密度降低、立方GaN形成最小化，并改善了GaN层的表面形貌。我们的分析表明，由于GaN与Si衬底之间的晶格和热失配，GaN层承受拉伸应变。为了管理这种应变，在生长100 nm GaN后插入了[公式：见原文][公式：见原文]N中间层。这种应变工程方法产生了光滑、无裂纹的GaN外延层，证明了使用[公式：见原文][公式：见原文]将GaN集成到硅技术中的潜力。
