Plasma-Assisted Net-Shape Deposition for Microfabrication

探索性研究将用于开发尺寸小于一毫米的新型微等离子体反应器，用于沉积金属、介电材料或用于微加工的聚合物。在适当的条件下，在微电极和对电极之间的常压下可以产生直径小于几百微米的强等离子体球。这种等离子体球是自我维持的，是“冷”型的，类似于微芯片制造中使用的高真空等离子体源。基于这种微等离子体球，提出了一种完全不同的微加工方法——等离子体辅助净形沉积（PAND）。采用PAND法，沉积将在常压下进行，从而消除了昂贵的高真空设备。此外，所需特征的净形状直接在基板表面“印刷”，从而消除了耗时和资本密集型的光刻。拟议的为期一年的项目还涉及影响PAND反应堆设计和运行的基本机制。由于大气压微等离子体放电的实验表征是一项具有挑战性的任务，因此提出了综合过程建模以了解系统的内在物理和化学特性。创新的建模策略将用于模拟这里讨论的独特放电（“冷”大气压微等离子体）。将为反应器开发一个高分辨率的放电物理模型，以检查各种工艺参数对原料气的电离和解离特性的影响。数值计算和实验室测量的结果将有助于表征“冷”大气压微等离子体。

Exploratory studies will be conducted for the development of novel micro plasma reactors that are less than a millimeter in size, for the deposition of metals, dielectric materials, or polymers for microfabrication. An intense plasma ball of less than a few hundred microns diameter can be generated under atmospheric pressure between a microelectrode and a counter electrode under suitable conditions. Such a plasma ball is self-sustaining and is of 'cold' type similar to the high vacuum plasma sources used in microchip manufacturing. Based on this micro plasma ball, a radically different method of microfabrication - plasma-assisted net-shape deposition (PAND) - is proposed. With the PAND method, the deposition will be carried out under atmospheric pressure to eliminate the costly high vacuum equipment. Also, the net shape of the desired feature is 'printed' at the substrate surface directly thereby eliminating the time-consuming and capital-intensive photolithography. The proposed one-year project also addresses the fundamental mechanisms affecting the design and operation of the PAND reactors. Since the experimental characterization of the atmospheric pressure micro-plasma discharge is a challenging task, comprehensive process modeling is proposed to understand the inherent physics and chemistry of the system. Innovative modeling strategies will be used to simulate the unique discharge ('cold' atmospheric pressure micro-plasma) addressed here. A high-resolution discharge physics model will be developed for the reactor to examine the effects of various process parameters on the ionization and dissociation characteristics of the feed gases. The results from numerical computations and laboratory measurements will help in characterizing the 'cold' atmospheric pressure micro-plasma.