The effect of Ultrasonic Wave on Czochralski Process for Growing Single Crystal

超声波对单晶生长直拉法的影响

• 批准号: 63550489
• 负责人: KUWABARA Mamoru
• 金额: $ 1.86万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63550489/
• 关键词: Czochralski Method; Single Crystal; Unidirectional Solidification; Ultrasonic Wave; Natural Convection; Double Diffusive Phenomena; Flow Visualization; チョコラルスキ-法; チョクラルスキー法; 熱対流; 流動解析

This study originally proposes a new Czoehralski process with radiating ultrasonic wave into liquid bath from which single crystal grows. This new method effectively utilizes ultrasonic standing wave established in the bath mainly so as to suppress thermal and solutal fluctuation induced by natural convection as well as to grow large crystal under suppressed supercooling of melt. Concluding remarks are as follows: 1. Flow regimes of natural convection in melt are classified and illustrated on a diagram as is specified by an interrelation between thermal and solutal Rayleigh numbers. 2. A resonant liquid depth exists at every depth equal to half of the wave length. 3. Degassed melt should be utilized in this process so as to suppress cavitation phenomena which interfere effective control of fluid convection. 4. The effect of ultrasonic wave on natural convection in degassed water is investigated on the basis of both the flow field visualized by a shadowgraph method and the sonic field d … More etected by an ultrasonic meter. Ultrasonic wave constrained a heated part of fluid at a sonic node whereas a cooled one at a sonic loop. The direction of force induced in water coincides with that of the radiation pressure acting on a hypothetically submerged fluid particle which has different acoustic properties from surrounding bulk depending on different density and different sonic velocity. 5. At increased density of ultrasonic energy, flow pattern visualized by the aluminum tracer method indicated that a stagnant area, in which moderate circulation of fluid occurs was formed nearby a sonic loop even at a uniform temperature field. This area is considered to be resulted from periodically distributed radiation pressure in fluid. 6. Using a simulated CZ device, the effect of ultrasonic wave on forced convection, natural convection and mixed convection in water has been investigated. At low density of ultrasonic energy, ultrasonic wave stabilizes the convection field whereas a stagnant area which emerges in increased energy case considerably changes even the flow field including forced convection. Less

本研究首次提出一种新的超音波辐射单晶生长的方法。这种新方法主要是有效地利用在熔池中建立的超声驻波来抑制由自然对流引起的温度和溶质波动，并在抑制熔体过冷的条件下生长大晶体。结论如下：1.本文对熔体自然对流的流型进行了分类，并用热力学和溶质瑞利数之间的相互关系作了说明。2.共振液体深度存在于等于波长的一半的每个深度处。3.在此过程中应使用脱气的熔体，以抑制干扰流体对流的有效控制的空化现象。4.本文根据阴影法显示的流场和声场图研究了超声波对脱气水中自然对流的影响。 ...更多信息 由超声波仪检测。超声波将被加热的流体约束在声速节点处，而将被冷却的流体约束在声速环处。在水中引起的力的方向一致的辐射压力作用在一个假设的淹没的流体颗粒，具有不同的声学特性，从周围的散装取决于不同的密度和不同的声速。5.在超声能量的密度增加，流动模式可视化的铝示踪剂方法表明，一个停滞区，其中发生适度的流体循环附近的声波回路，即使在均匀的温度场形成。这一区域被认为是流体中周期性分布的辐射压力的结果。6.利用模拟CZ装置，研究了超声波对水中强制对流、自然对流和混合对流的影响。在低密度的超声波能量，超声波稳定的对流场，而在增加的能量的情况下出现的停滞区显着改变，甚至流场，包括强制对流。少

项目成果

尾崎幸克: "超音波による液中熱対流の制御" 材料とプロセス. 3. 131-131 (1990)

Yukatsu Ozaki：“超声波控制液体中的热对流”材料与工艺 3. 131-131 (1990)。

尾崎幸克: "液中における熱対流の超音波による抑制" 材料とプロセス. 2. 274-274 (1989)

Yukatsu Ozaki：“超声波抑制液体中的热对流”材料与工艺 2. 274-274 (1989)。

Keiji Okumura: "Numerical Analysis and Model Experiment on Thermosolutal Convection during Unidirectional Solidification in the Vertical Direction" Tetsu-to-Hagane, 75, p.618, 1989.

Keiji Okumura：“垂直方向单向凝固过程中热溶质对流的数值分析和模型实验”Tetsu-to-Hagane，75，第 618 页，1989 年。

Keiji Okumura: "Theoretical Analysis on Thermosolutal Convection during Unidirectional Solidification in the Vertical Direction" 2nd Sympo. on Computational Dynamics, p.9, 1989.

Keiji Okumura：“垂直方向单向凝固过程中热溶质对流的理论分析”第二次研讨会。

奥村圭二: "垂直一方向凝固時における熱溶質対流の数値解析" 第2回計算力学講演会講演概要集. 9-10 (1989)

Keiji Okumura：“垂直单向凝固过程中热溶质对流的数值分析”第二届计算力学会议摘要 9-10 (1989)。