Environmentally friendly plasma processing

化合物半导体是实现净零排放的多项关键使能技术的基础。许多具有高全球变暖潜势(GWP)的气体在这些技术的制造步骤中起到了重要作用。该项目的重点是全氟化合物，特别是SF6和NF3，其全球升温潜能值分别为23500和17200。全氟碳化物在等离子体刻蚀中用作氟自由基源，并用于清洗等离子体增强化学气相沉积(PECVD)室。由于分子的稳定性，SF6和NF3是具有较长大气寿命的合成分子。前体供应链中的大气损失，以及等离子处理工具废气中未破裂分子的排放，大大增加了半导体工业的温室气体净排放量。目前，将此类排放降至最低的努力主要集中在工艺优化和使用点减少系统上。我们的目标是通过系统研究全球变暖潜能值低的替代品来消除这些排放。此外，我们将研究减排和工艺优化技术，以最大限度地减少废气的影响。该项目与行业非常相关，因此将重点放在可伸缩性上，同时保持CS结构的质量。

Compound Semiconductors are the basis of multiple key enabling technologies in the move to net zero emissions. A number of gases of high Global Warming Potential (GWP) are instrumental in the fabrication steps of such technologies. This project focusses on Perfluorinated Compounds (PFCs), particularly SF6 and NF3 with GWPs of 23500 and 17200 respectively. PFCs are used as sources of fluorine radicals in Plasma Etching, and for the cleaning of Plasma Enhanced Chemical Vapour Deposition (PECVD) chambers. SF6 and NF3 are synthetic molecules with long atmospheric lifetimes, in virtue of the molecule's stability. Losses to atmosphere within the precursor supply chains, and the emission of uncracked molecules in the exhaust of plasma processing tools contributes significantly to the net greenhouse gas emissions of the semiconductor industry. Current attempts to minimise such emissions focus on process optimisation and point of use abatement systems. We aim to eliminate these emissions through the systematic investigation of low GWP alternatives. Additionally, we'll investigate abatement and process optimisation techniques to minimise impacts from exhaust gasses. This project is extremely relevant to industry, and thus will focus heavily on scalability while maintaining the quality of CS structures.