Collaborative Research: Studies of Explosive Crystallization

提案编号：CTS-0431431 CTS-0431409主要研究者： Benard J. Matkowsky和亚历山大A. Golovin Costas Grigoropoulos所属机构： 非晶材料的爆炸结晶是一个迷人的现象，吸引了工程师，物理学家，材料科学家和其他人的关注超过二十年。它本身表现为固体材料从亚稳态非晶态到稳定晶态的热激活的高度放热相变，其以自蔓延结晶前沿的形式发生。可以通过机械产生的局部热上升或通过激光束来触发前传播。激光束触发的非晶半导体薄膜的爆炸结晶是一种广泛使用的现代技术，用于生产绝缘体上硅结构，该绝缘体上硅结构在各种光伏器件如太阳能电池或红外探测器中具有许多应用，在平板显示器中具有低成本、低功耗，拟议项目的目标是发起和发展西北大学理论小组与实验组在伯克利分校，进行系统的理论和实验研究的几个重要方面的爆炸结晶，以前没有研究。合作将集中在爆炸结晶前沿和由此产生的微观结构所表现出的不稳定性的非线性动力学的数学建模和实验研究。具体而言，我们建议调查的稳定性和非线性动力学的爆炸结晶前沿在几种不同的模式的正面传播，以及爆炸结晶合金和掺杂剂的结晶动力学的影响。从基本的观点来看，所提出的研究的意义在于阐明诸如在几种模式中爆炸结晶前沿的不稳定性和非线性动力学等重要效应，这些模式提供了远离热力学平衡的系统中复杂非线性行为的例子。这一结果将加深我们对非晶薄膜爆炸晶化现代工艺过程的理解。建立的合作将使我们能够在未来的联合研究中进一步深入到爆炸结晶材料的微观结构的更详细的研究，这是控制和优化过程的必要先决条件。拟议研究的更广泛影响在于其跨学科性质，以及对科学家和工程师的重要性。它还将为在未来的合作研究阶段培养研究生创造良好的基础，为他们提供独特的机会，参与工程，应用物理和应用数学前沿的重要研究，结合了理论和实验的组成部分。这项研究已经由数学和物理科学理事会数学科学部和工程局化学和运输系统司。 资金来自数学科学：与科学和工程计划接口的创新，公告NSF 04-538。

Proposal Number: CTS-0431431CTS-0431409Principal Investigator: Benard J. Matkowsky and Alexander A. GolovinCostas GrigoropoulosAffiliation: Northwestern UniversityUniversity of California-BerkeleyProposal Title: Collaborative Research: Studies of explosive crystallizationAbstractExplosive crystallization of amorphous materials is a fascinating phenomenon that has attracted much attention from engineers, physicists, materials scientists and others for over two decades. It manifests itself as a thermally activated, highly exothermic phase transition of a solid material from a metastable amorphous state to a stable crystalline state, that occurs in the form of a self-propagating crystallization front. The front propagation can be triggered by a local heat rise produced mechanically, or by a laser beam. The laser-beam-triggered explosive crystallization of amorphous semiconductor films is a widely used modern technology for producing silicon-on-insulator structures that have many applications in various photovoltaic devices like solar cells or infrared detectors, low-cost, low-power consuming at panel displays, etc. The objective of the proposed project is to initiate and develop a fruitful collaboration between the theoretical group at Northwestern and the experimental group at Berkeley, to carry out systematic theoretical and experimental investigations of several important aspects of explosive crystallization that have not been previously studied. The collaboration will focus on mathematical modeling and experimental studies of nonlineardynamics of instabilities exhibited by explosive crystallization fronts and the resulting microstructures. Specifically, we propose to investigate the stability and nonlinear dynamics of explosive crystallization fronts in several different modes of frontal propagation, as well as explosive crystallization in alloys and the effect of dopants on the crystallization dynamics. From the fundamental point of view, the significance of the proposed research is in elucidating such important effects as the instabilities and nonlinear dynamics of explosive crystallization fronts in several modes that provide examples of complex nonlinear behavior in systems far from thermodynamic equilibrium.From the technological point of view, the results will enhance our understanding of the modern technological process of explosive crystallization in thin amorphous films. The established collaboration will allow us to move further in our future joint research to more detailed investigations of microstructure in explosively crystallizing materials which is a necessary prerequisite to control and optimization of the process. The broader impact of the proposed research lies in its interdisciplinary nature, its importance for bothscientists and engineers. It will also create a sound basis for training graduate students in future stages of the collaborative research that will provide them with the unique opportunity to participate in important research at the cutting edge of engineering, applied physics and applied mathematics, combining both theoretical and experimental components.This research has been funded jointly by the Division of Mathematical Sciences in the Mathematics and Physical Sciences Directorate and the Division of Chemical and Transport Systems in the Engineering Directorate. Funding is from the Mathematical Sciences: Innovations at the Interface with the Sciences and Engineering Program, Announcement NSF 04-538.