Silicon Alley Silicon Alley Silicon Alley, centered around the Flatiron district in Manhattan, is an area of high tech industries. The term was coined in the 1990s during the dot-com boom, as a reference to <nowiki>"Silicon Valley", the tech center in California. As the New York tech industries began a revival around 2003, the businesses spread outside of Manhattan making the term 'Silicon Alley'</nowiki> somewhat obsolete. , New York City hosted 300,000 employees in the tech sector. In 2015, New York generated over US$7.3 billion in venture capital investment. High technology startup companies and employment are growing in New York City and
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