Silicon Alley across the metropolitan region, bolstered by the city's emergence as a global node of creativity and entrepreneurship, social tolerance, and environmental sustainability, as well as New York's position as the leading Internet hub and telecommunications center in North America, including its vicinity to several transatlantic fiber optic trunk lines, the city's intellectual capital, and its extensive outdoor wireless connectivity. The term "Silicon Alley" was derived from the long established Silicon Valley in California. It was originally centered in the Flatiron District, in the vicinity of the Flatiron Building at Fifth Avenue near Broadway and 23rd Street, straddling Midtown and Lower
Polycrystalline silicon grain boundaries, see figure 1. The resistivity, mobility, and free-carrier concentration in monocrystalline silicon vary with doping concentration of the single crystal silicon. Whereas the doping of polycrystalline silicon does have an effect on the resistivity, mobility, and free-carrier concentration, these properties strongly depend on the polycrystalline grain size, which is a physical parameter that the material scientist can manipulate. Through the methods of crystallization to form polycrystalline silicon, an engineer can control the size of the polycrystalline grains which will vary the physical properties of the material. The use of polycrystalline silicon in the production of solar cells requires