The occurrence of a large number of polytypes in SiC and the strong influence this has on many of its properties is well known. Rhombohedral (trigonal) 15R-SiC is the second commonest polytype. Rhombohedral polytypes, such as 21R- and 27R-SiC, have also been identified but very rarely....
百度试题 题目α-SiC、β-SiC、6H-SiC、15R-SiC在晶体构造上差别,列举几种SiC合成办法及反映式 相关知识点: 试题来源: 解析 答:表1-26 二氧化硅碳热还原法:SiO2+3C=SiC+2CO 气相沉积法:反馈 收藏
摘要: 碳化硅(SiC)有200多种不同的晶型结构,对应于不同晶型的光学及电子能带特性具有明显差异,国内外研究者对于SiC晶体材料的光学特性研究较多[1,2].本文重点研究了4H-,6H-及15R-SiC单晶的吸收与拉曼(Raman)光谱特性.SiC晶体样品均为垂直于生长方向(0001)切割,经双面研磨抛光...
无紫外光照射下n型15R—SiC及6H—SiC晶体的电化学腐蚀 维普资讯 http://www.cqvip.com
The tungsten-related optical centers are reported in 4H-, 6H-, and 15R-SiC. Further, a crystal field model for a tungsten atom occupying a Si-site is suggested. This crystal field model is in agreement with the experimental data available: polarization, temperature dependence and magnetic field...
6H-SiC，4H-SiC，3C-SiC，2H-SiC，15R-SiC，51R-SiC的形成温度各是多少？
6H-SiC，4H-SiC，3C-SiC，2H-SiC，15R-SiC，51R-SiC的形成温度各是多少？
The optical absorption of 4H-, 6H- and 15R-SiC single crystals has been measured at room temperature. The band gaps were calculated, and the reasons for ba... LI Xiang-Biao,EW Shi,ZZ Chen - 《Chinese Journal of Structural Chemistry》 被引量: 0发表: 2007年 Electronic Configuration of Tun...
The Raman scattering intensity of the unfolded longitudinal optical mode shows a pronounced decrease for all polytypes in the UV-spectral range, except for 3C-SiC. It is shown, that the position of the decrease in the intensity is related with the ...
On the other hand, the Raman spectrum of the bottom region, which was distant from the laser irradiation, exhibited Raman modes at 514, 785, and 965 cm -1, that correlate to 6H-SiC and 15R-SiC, respectively [36–39]. The Raman results indicate that sintering of the composite particles ...