Microelectronics materials processing, application

M. G. Pecht, L. Nyugen, and E. B. Hakim, Plastic Encapsulated Microelectronics Materials, Processes Quality, Reliability and Applications, John Wiley Sons, Inc., New York, 1995. 

Excimer lasers are of great importance for UV and vacuum UV (VUV) spectroscopy and photochemistry. They are also found in a wide range of applications. For example, they are used in micromachine medical devices, including refractive surgery, in photo-lithography for the microelectronics industry, for material processing, as optical pump sources for other type of lasers (dyes), and so on. More details about excimer lasers can be found in Rodhes (1979). 

The silicon employed for microelectronic and photovoltaic applications must first go through extensive processing to ensure that the material is of utmost purity. This section will describe these steps, with a discussion of perhaps the most intriguing conversion in the realm of materials science the synthesis of high-purity polished silicon wafers from a naturally occurring form of silicon - sand. 

Photochemical surface reactions of polymer systems are an important field not only from the point of view of micro-electronic materials processing, but also from a more general scientific and materials application perspective. We have reviewed our studies in this field, which include investigations of excimer laser ablation, studies of the photo-oxidation of polymer surfaces, and the use of surface cross-linking and surface polymer depositions for microlithographic applications. With the increasing miniaturization of microelectronic devices, the fundamental and the applied aspects of surface photochemistry of polymers becomes increasingly important. 

The acoustic microscopy s primary application to date has been for failure analysis in the multibillion-dollar microelectronics industry. The technique is especially sensitive to variations in the elastic properties of semiconductor materials, such as air gaps. SAM enables nondestructive internal inspection of plastic integrated-circuit (IC) packages, and, more recently, it has provided a tool for characterizing packaging processes such as die attachment and encapsulation. Even as ICs continue to shrink, their die size becomes larger because of added functionality in fact, devices measuring as much as 1 cm across are now common. And as die sizes increase, cracks and delaminations become more likely at the various interfaces. 

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