Off-Equilibrium Doping of Semiconductor Nanowires

为了将纳米线的掺杂控制在超过热力学平衡极限的水平，本奖项的研究目标是：1)证明半导体纳米线中的极端掺杂水平与体中相当；2)显示沿径向均匀的活化纳米线掺杂；3)打破纳米线材料的天然掺杂倾向。建议开展外展活动，通过培训和指导来自不同背景的学者来促进纳米科学领域的多样性。该方法将采用离子注入和脉冲激光处理相结合的极度非平衡技术来控制气液固合成纳米线的掺杂动力学和物理特性。申请人?初步结果表明，与其他平衡方法相比，该方法在掺杂硅纳米线的所有技术指标上都具有优越性。将制作用于评价活性掺杂剂浓度和分布的单纳米线器件。采用有限元模型模拟掺杂纳米线的静电学和电动力学，分析实验数据。如果成功，该研究将为新一代微电子和光电子技术奠定材料基础，从而造福整个社会。我们将发现一种新的方法，使半导体纳米线达到前所未有的高浓度和均匀分布。许多技术上重要的半导体的天然掺杂倾向和差异将被克服。这一成就将在理解纳米材料的缺陷物理和动力学方面产生重大进展。这种掺杂策略的论证将促进半导体纳米结构合成和器件加工的创新。将获得有关材料科学和纳米尺度加工的新知识。

Aimed at controlling the doping of nanowires to the level exceeding the thermodynamical equilibrium limit, the research objectives of this award are: 1) to demonstrate extreme doping levels in semiconductor nanowires comparable to those in the bulk, 2) to show uniform activated nanowire doping along the radial direction; and 3) to break the natural doping propensity of nanowire materials. Outreach activities are proposed to promote diversity in the nanoscience sector by the training and mentoring of scholars from diverse backgrounds. The approach will be to employ an extremely off-equilibrium technique combining ion implantation and pulsed-laser processing to control the doping kinetics and physics in nanowires synthesized by the vapor-liquid-solid method. The proposer?s preliminary results have shown superiority of this technique on all technical metrics in doping silicon nanowires compared to other equilibrium methods. Single-nanowire devices will be fabricated for evaluation of activated dopant concentration and distribution. Finite element modeling will be performed to simulate the electrostatics and electrodynamics of doped nanowires for analyzing experimental data.If successful, the research will benefit society at large by laying a materials foundation for a new generation of microelectronic and optoelectronic technologies. A new strategy will be discovered to dope semiconductor nanowires at unprecedentedly high concentrations and uniform distribution. The natural doping propensity and disparity of many technologically important semiconductors will be overcome. The achievement would produce significant advancements in the understanding of defect physics and kinetics in nanoscale materials. Demonstration of such doping strategy will promote innovations in semiconductor nanostructure synthesis and device processing. New knowledge will be gained concerning the materials science and processing at the nanoscale.