Noise Spectroscopy for the Investigation and Characterization of Ultra-Thin Gate Dielectrics

我们的研究目标是开发一种新的高灵敏度技术，用于表征和研究先进的超薄栅极电介质中的应力诱导击穿，这些电介质构成了下一代最先进和下一代VLSI技术的关键部件之一。我们的噪声光谱技术是基于这样一种认识，即电介质击穿必然涉及由高能载流子（电子或空穴）的冲击引起的原子键的断裂和重排，这必然导致载流子阱态的形成。隧道中的过量电流噪声，通过栅极电介质的泄漏电流代表了这些陷阱的存在和性质的极其敏感的探针，这些陷阱在隧道过程中充当垫脚石，因此，通过噪声光谱对过量噪声进行详细和系统的调查，有可能在生长后立即提供关于介电薄膜质量的直接信息，以及电介质击穿的途径。这项研究在短期内的潜在影响是开发出一种更敏感和信息更丰富的技术来确定超薄栅极电介质的质量和鲁棒性，这将对硅超大规模集成电路工业有用，补充传统的充电击穿和CV技术。从长远来看，当对电介质击穿的物理机制有了清晰的认识时，它应该会导致设计和制造更好、更坚固的栅极电介质的能力，例如，通过添加微量杂质来抑制原子运动并减少陷阱的形成。在教育方面，我们打算招收三名研究生，一名研究噪声光谱技术，另一名研究介电生长。这两个方面都将涉及各自领域的最先进方法。此外，我们计划最大限度地促进工业联系。

The goal of our research is to develop a new and highly sensitive technique for the characterization and investigation of stress-induced breakdown in the advanced, ultra-thin gate dielectrics which constitute one of the key components for next state-of-the-art and next generation VLSI technology. Our technique of Noise Spectroscopy is based on the realization that dielectric breakdown must involve the breakage and rearrangement of atomic bonds arising from the impact of energetic carriers (electrons or holes) which invariably leads to the formation of CARRIER TRAP STATES. EXCESS CURRENT NOISE in the tunneling, leakage current through gate dielectrics represents an extremely sensitive probe of both the presence and the nature of these TRAPS which serve as stepping stones in the tunneling process and therefore the detailed and systematic investigation of excess noise via Noise Spectroscopy has the potential of providing direct information on the QUALITY OF DIELECTRIC FILMS immediately after growth as well as the PATHWAY TO DIELECTRIC BREAKDOWN.The potential impact of this research in the shorter term is the development of a more sensitive and informative technique to ascertain the quality and robustness of ultra thin gate dielectrics which will be useful to the silicon VLSI industry complementary to conventional charge to breakdown and CV techniques. In the longer term, when a clear understanding of the physical mechanism of dielectric breakdown is achieved it should lead to the ability to design and manufacture better and more robust gate dielectrics e.g. via addition of trace impurities to pin atomic motion and reduce trap formation. In terms of education, we intend to involve three graduate students, one for the Noise Spectroscopy technique and the others for dielectric growth. Both aspects will involve state-of-the-art methods in the respective areas. In addition we plan to foster industrial ties to the fullest extent.