関連する実験動画
Updated: Jun 4, 2026

12:04
Microfluidic Preparation of Liquid Crystalline Elastomer Actuators
Published on: May 20, 2018
シリコンの結晶化過程における液体多形化の役割
Caroline Desgranges1, Jerome Delhommelle
1Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58201, USA.
Journal of the American Chemical Society
|February 17, 2011
まとめ
シリコン結晶化は,高密度液体 (HDL) 段階内で形成される低密度液体ポリモルフ (LDL) によって推進されます. この液体ポリモルフ経路は,結晶核形成のエネルギーバリアを大幅に低下させます.
科学分野:
- マテリアルサイエンス 材料科学
- 物理化学 物理化学
- 計算物理学の物理
背景:
- シリコン結晶化は,半導体製造において極めて重要です.
- 核形成経路を理解することは,結晶形成を制御する鍵です.
- シリコンの液体ポリモルフは仮説化されているが,実験的に確認されていない.
研究 の 目的:
- シリコン結晶化における液体ポリモルフの役割を明らかにする.
- 溶けたシリコンの核形成経路を調査する.
- 液体ポリモルフィズムを組み込むことにより,既存の核化理論に挑戦する.
主な方法:
- シリコンの融解行動をモデル化するために,分子動力学シミュレーションが採用されました.
- 分析は,液相の構造的および動的性質に焦点を当てた.
- 核形成経路を決定するために,自由エネルギー計算を行いました.
主要な成果:
- シリコンメルトは低冷却時に高密度液体 (HDL) ポリモルフとして存在します.
- 結晶化は,HDL内の低密度液体 (LDL) ポリモルフドロップレットの形成によって開始されます.
- 結晶胚形成は,LDLドロップレット内で発生し,核形成エネルギー障壁を減少させます.
結論:
- 液体ポリモルフは,シリコン結晶化において重要な役割を果たします.
- 古典的な核化理論とオストワルドの法則は,液体ポリモルフを持つシステムに対して修正を必要とする.
- この発見は結晶化プロセスを理解し制御するための新しい枠組みを提供します.
関連する概念動画
Polymer Classification: Crystallinity
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Recrystallization: Solid–Solution Equilibria
Recrystallization is a purification technique used to separate impurities from solid compounds. In this technique, no chemical reactions occur. Instead, it exploits physical properties only, specifically, the solubility differences between the desired compound and impurities, either at a single temperature or at different temperatures, and under other selected conditions. The solid-solution equilibrium (solubility equilibrium) of each component in the solution represents a binary phase...
Classification and Mechanical Properties of Synthetic Polymers
Synthetic polymers are classified as elastomers, fibers, or plastics based on their crystallinity. Crystallinity, the degree of long-range order in the solid state, influences the mechanical properties (stretching or contracting) of elastomers. Elastomers are flexible polymers that can expand or contract easily upon the application of an external force. They have numerous crosslinks that pull them back into their original shape when stress is removed. Silicones, for instance, are highly elastic...
Crystal Growth: Principles of Crystallization
Crystallization is a phase transformation process in which crystals are precipitated from a supersaturated solution or formed from other sources. During crystallization, atoms or molecules arrange themselves into a well-defined, rigid crystal lattice to minimize energy.
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent – the...
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent – the...
Polymer Classification: Stereospecificity
Polymerization generates chiral centers along the entire backbone of a polymer chain. Accordingly, the stereochemistry of the substituent group has a significant effect on polymer properties. Polymers formed from monosubstituted alkene monomers feature chiral carbons at every alternate position in the polymer backbone. Relative to the predominant orientation of substituents at the adjacent chiral carbons, the polymer can exist in three different configurations: isotactic, syndiotactic, and...
Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism
Polymorphism refers to the existence of a drug substance in multiple crystalline forms, known as polymorphs. Recently, this term has been expanded to include solvates (forms containing a solvent), amorphous forms (non-crystalline forms), and desolvated solvates (forms from which the solvent has been removed).
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...

