摘要
在MPCVD单晶金刚石同质外延生长中,为实现对等离子体的调控,进而改善单晶金刚石二维扩大生长中表面形貌的均匀性,在单晶金刚石周围放置一中间为方孔的圆形衬环即约束环。结合发射光谱、表面形貌、白光干涉测试及拉曼光谱表征结果研究了约束环的尺寸对金刚石均匀性、质量及生长速率的影响。结果表明:在其他沉积参数相同的条件下,增大约束环的直径会降低等离子体中C2基团的浓度,从而降低单晶金刚石的生长速率,但有利于获得高质量的生长面形貌。当约束环的直径从10 mm增加到14 mm时,单晶金刚石的生长速率由10.4μm/h减小到6.4μm/h,单晶生长面上的多晶及丘包状缺陷被完全抑制,拉曼光谱中位于1460 cm-1附近的波包基本消失,单晶质量显著提高。采用直径14 mm的约束环,用同一HPHT种晶的上下两面分别进行二维扩大生长实验,两个面的尺寸分别由3 mm×3 mm扩大至3.82 mm×3.89 mm及3.97 mm×4.07 mm,适当的约束环设置有利于单晶金刚石的侧向外延。
In the homoepitaxial growth of single crystal diamond by MPCVD,in order to realize the control of the plasma and improve the uniformity of the surface morphology in the two-dimensional expanded growth of single crystal diamond,a circular lining ring with a square hole in the middle,the confinement ring,is placed around the single crystal diamond.The effect of the size of the confinement ring on the uniformity,quality and growth rate of diamond was studied by combining the results of emission spectroscopy,surface morphology,white light interference measurement and Raman spectroscopy.The results showed that under the same conditions of other deposition parameters,increasing the diameter of the confinement ring would reduce the concentration of C2groups in the plasma,thereby reducing the growth rate of single crystal diamond,but it was beneficial to obtaining high-quality growth surface morphology.When the diameter of the confinement ring increased from 10 mm to 14 mm,the growth rate of single crystal diamond decreased from 10.4 μm/h to 6.4 μm/h,the polycrystalline and dome-shaped defects on the single crystal growth surface were completely suppressed,and the wave packet near 1460 cm-1in the Raman spectrum basically disappeared,and the quality of the single crystal was significantly improved.Two-dimensional expansion growth experiments were performed on the upper and lower sides of the same HPHT seed crystal using confinement rings with a diameter of 14 mm;the dimensions of the two sides were enlarged from 3 mm × 3 mm to 3.82 mm × 3.89 mm and 3.97 mm × 4.07 mm,respectively,and the appropriate confinement ring settings are beneficial to the lateral epitaxy of single crystal diamond.
作者
高登
马志斌
GAO Deng;MA Zhibin(School of Material Science and Engineering,Hubei Key Laboratory of Plasma Chemical and Advanced Materials,Wuhan Institute of Technology,Wuhan 430073,China)
出处
《真空科学与技术学报》
CAS
CSCD
北大核心
2022年第7期541-546,共6页
Chinese Journal of Vacuum Science and Technology
基金
国家自然科学基金项目(11575134)。
关键词
化学气相沉积
单晶金刚石
白光干涉
表面形貌
CVD
Single crystal diamond
White light interference
Surface morphology
