CAJ | 학술논문

为了提高生长在硅衬底上的硅锗弛豫衬底的质量，提出了低温锗量子点缓冲层技术，分析了该技术在应变弛豫的促进，表面形貌的改善，位错密度的降低等方面的作用机理。基于低温锗量子点缓冲层技术，利用超高真空化学气相淀积系统，在硅衬底上生长出高质量的硅锗弛豫衬底。锗组份为0.28，厚度不足380 nm的硅锗弛豫衬底，应变弛豫度达到99%，表面没有Cross-hatch形貌，表面粗糙度小于2 nm，位错密度低于105 cm-2。
위료제고생장재규츤저상적규타이예츤저적질량，제출료저온타양자점완충층기술，분석료해기술재응변이예적촉진，표면형모적개선，위착밀도적강저등방면적작용궤리。기우저온타양자점완충층기술，이용초고진공화학기상정적계통，재규츤저상생장출고질량적규타이예츤저。타조빈위0.28，후도불족380 nm적규타이예츤저，응변이예도체도99%，표면몰유Cross-hatch형모，표면조조도소우2 nm，위착밀도저우105 cm-2。
A method for the growth of strain-relaxed SiGe virtual substrate (VS) on Si substrate with low temperature Ge (LT-Ge) islands buffer was proposed and studied. The role of LT-Ge islands buffer played in the mechanism of strain adjustment, surface modification and dislocation annihilation was analyzed. High-quality strain-relaxed SiGe VS was grown on Si(100) substrate in an ultra-high vacuum chemical vapor deposition system by LT-Ge islands buffer. Si0.72Ge0.28 VS with a thickness of only 380 nm had a strain relaxation degree of 99%. No cross-hatch pattern was observed on the SiGe VS surface and the surface root-mean-square roughness was less than 2 nm. The threading dislocation density was lower than 105 cm-2.