Uniform Monolayer Pealing by Cyclic Etching of Gallium Arsenide (100) and Silicon (100) Surfaces

9307259 Kummel本研究利用饱和剂量的Cl2和激光诱导解吸，通过精确的整数层来精确蚀刻GaAs（100）和Si（100）。分子氯是必需的，因为它只吸收覆盖在这两个表面的单层。激光诱导热解吸的关键品质是(a)样品的均匀性；(b)完全去除所有蚀刻产物；(c)表面恢复到干净有序的状态。这些特性将通过使用纳秒激光脉冲序列或单微秒激光脉冲而不是传统的纳秒单脉冲技术来寻求。单层剥离技术对量子阱器件的发展至关重要，因为如果成功，它将允许蚀刻到两个薄半导体层之间的精确界面，如GaAs和AlGaAs。本研究的目标是设计一种在室温下蚀刻GaAs（100）和Si（100）而不破坏表面的方法，并对蚀刻深度进行超精确的原子水平控制。提出了一种氯循环蚀刻和激光诱导热脱附的单层剥离技术。单层剥离技术对于使用化合物半导体量子阱等结构的先进电子和光子器件和集成电路的发展至关重要，因为它将为关键的制造工艺提供基础，蚀刻到两个超薄半导体层（如GaAs和AlGaAs）之间的精确界面。

9307259 Kummel This research addresses precise etching of GaAs(100) and Si(100) by an exact integral number of monolayers using saturation dosing of Cl2 followed by laser induced desorption. Molecular chlorine is required because it only absorbs to a coverage of one monolayer on these two surfaces. The critical qualities for the laser induced thermal desorption are (a) uniformity across the sample; (b) complete removal of all etching products; (c) restoration of the surface to a clean well-ordered state. These characteristics will be sought through the use of sequences of nanosecond laser pulses or single microsecond laser pulses rather than the conventional nanosecond single pulse technique. The monolayer peeling technique is critical to the development of quantum well devices because, if successful, it would allow etching to the exact interface between two thin semiconductor layers such as GaAs and AlGaAs. %%% The goal of this study is to devise a method of etching GaAs(100) and Si(100) at room temperature without surface damage and with an ultra-precise atomic level control over etch depth. This proposed technique of monolayer peeling is cyclic etching with chlorine and laser induced thermal desorption. The monolayer peeling technique is critical to the development of advanced electronic and photonic devices and integrated circuits using structures such as compound semiconductor quantum wells, because it would provide the basis for a critical fabrication process, etching to the exact interface between two ultra-thin semiconductor layers such as GaAs and AlGaAs.