SBIR Phase I: Investigation of Charge Trapping in Plasma Enhanced Chemical Vapor Deposition (PECVD) Dielectrics Using Electrostatically Actuated Mechanical Resonators

这个小企业创新研究（SBIR）第一阶段项目将开发一种新的方法来测量电荷陷阱在电子束。我们的方法的可行性，通过将其应用于等离子体增强化学气相沉积（PECVD）的氮化物和氧化物的表征将被证明。 这些材料的沉积化学留下陷阱位点，当受到大电场时捕获电荷。陷阱电荷影响使用这些电荷的微机电（MEM）器件的稳定性和性能。 提出了一种新的技术，使用谐振，静电致动的机械结构来测量被困在悬浮的电介质层中的电荷。 使用网络分析仪测量的器件阻抗的真实的部分可以与由俘获电荷引起的电介质中的电场变化相关联。PECVD半导体是MEM器件的关键组成部分，年销售额达到35亿美元（光学元件、RF元件和医学成像元件）。虽然该技术本身不是商业产品，但它广泛适用于利用悬浮PECVD介电层的MEMS器件的工程，例如射频（RF）开关和微镜。 这种在高工艺敏感性PECVD工艺中对电荷捕获的控制将使我们能够实现我们的超声设备在医学成像应用中的全部商业潜力。

This Small Business Innovation Research (SBIR)Phase I project will develop a novel way to measure charge trapping in dielectrics. The feasibility of our method by applying it to the characterization of plasma enhanced chemical vapor deposition (PECVD) nitride and oxide will be demonstrated. The deposition chemistry of these materials leaves trap sites that capture charge when subjected to large electric fields. Trapped charge affects the stability and performance of micro-electro-mechanical (MEM) devices that employ these dielectrics. A novel technique that uses a resonant, electro-statically actuated mechanical structure to measure charge trapped in a suspended dielectric layer is proposed. The real part of the device impedance, measured using a network analyzer, can be correlated to changes in electric field in the dielectric resulting from trapped charge..PECVD dielectrics are critical constituents in MEM devices that enable $3.5 Billion in annualized sales (optical components, RF components, and medical imaging components). Although the technique itself is not a commercial product, it is broadly applicable to the engineering of MEMs devices utilizing suspended PECVD dielectric layers, such as radio frequency (RF) switches and micro-mirrors. This control of charge trapping in highly process sensitive PECVD dielectrics will allow us to realize the full commercial potential of our ultrasound devices in medical imaging applications.