Rapid Crystallization of Levitated and Undercooled Semiconducting Material Melts
Rapid Crystallization of Levitated and Undercooled Semiconducting Material Melts
复制标题
DOI：
10.1007/s11837-012-0423-0
复制
发表时间：
2012-09-01
期刊：
影响因子：
2.6
通讯作者：
Nagayama, Katsuhisa
中科院分区：
文献类型：
--
作者：
Ishibashi, Yusuke;Kuribayashi, Kazuhiko;Nagayama, Katsuhisa
利用CO_2激光器电磁悬浮装置，进行了Si和Ge的无容器晶化。从界面形貌的角度，将生长速度与过冷度的关系分为三个区域。在区域I和II中，虽然生长晶体的形态是不同的：在区域I中的板状针状晶体和在区域II中的多面枝晶，但在这两个区域中的生长速度从根本上由热扩散率和由潜热释放引起的温度升高来缩放。这一结果意味着生长速度可以用热扩散率和生长动力学的乘积来表示。的枝晶形态的分析表明，在区域I和II中的晶体生长的动力学表示在两个平行的双胞胎的边缘处形成的凹角处的二维成核。在区域III中，热扩散控制的界面附着动力学控制所描述的修改后的威尔逊-弗伦克尔模型。
Using a CO2 laser-equipped electromagnetic levitator, we carried out the containerless crystallization of Si and Ge. From the point of interface morphologies, the relation between growth velocities and undercoolings was classified into three regions. In regions I and II, although the morphologies of growing crystals are different: plate-like needle crystals in region I and facetted dendrite at region II, the growth velocities in these two regions are fundamentally scaled by the thermal diffusivities and the temperature increase caused by the release of the latent heat. This result means that the growth velocity can be expressed by the product of the thermal diffusivity and the growth kinetics. An analysis of the dendrite morphologies revealed that the kinetics of crystal growth in regions I and II represent two-dimensional nucleation at the reentrant corner formed at the edge of the two parallel twins. In region III, thermal diffusion-controlled interface attachment kinetics control as described by a modified Wilson-Frenkel model.