tailieunhanh - Wave Propagation 2010 Part 7

Tham khảo tài liệu 'wave propagation 2010 part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 9 Detection and Characterization of Nano-Defects Located on Micro-Structured Substrates by Means of Light Scattering Pablo Albella 1 Francisco Gonzalez 1 Fernando Moreno 1 José María Saiz1 and Gorden Videen2 University of Cantabria 2Army Research Laboratory Spain 2USA 1. Introduction Detection and characterization of microstructures is important in many research fields such as metrology biology astronomy atmospheric contamination etc. These structures include micro nano particles deposited on surfaces or embedded in different media and their presence is typical for instance as a defect in the semiconductor industry or on optical surfaces. They also contribute to SERS and may contribute to solar cell performance Sonnichsen et al. 2005 Stuart et al. 2005 Lee et al. 2007 . The central problem related to the study of morphological properties of microstructures size shape composition density volume etc. is often lumped into the category of Particle Sizing and has been a primary research topic Pena et al. 1999 Moreno and Gonzalez 2000 Stuart et al. 2005 Lee et al. 2007 . There are a great variety of techniques available for the study of micro- and nanostructures including profilometry and microscopy of any type optical electron atomic force microscopy AFM etc. Those based on the analysis of the scattered light have become widely recognized as a powerful tool for the inspection of optical and non-optical surfaces components and systems. Light-scattering methods are fast flexible and robust. Even more important they are generally less expensive and non-invasive that is they do not require altering or destroying the sample under study Germer et al. 2005 Johnson et al. 2002 Mulholland et al. 2003 . In this chapter we will focus on contaminated surfaces composed of scattering objects on or above smooth flat substrates. When a scattering system gets altered either by the presence of a defect or by any kind of irregularity on its surface the scattering pattern changes in a way