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Rotating Pocket Heater
A rotating pocket heater, also called pocket heater or Kinder heater, holds and rotates a substrate during vacuum deposition. During rotation, the substrate is sequentially exposed to more than one environment, for example, heat, oxygen, metal vapor, etc. Rotating pocket heaters has been used in reactive evaporation system to create YBa2Cu3O7 layers on planar semiconductor wafers. Magnesium diboride The illustration on the right shows an example of a pocket heater being used to deposit a layers of magnesium diboride on a substrate. A vertical shaft (32) turns a horizontal disk (30) several hundred rotations per minute (RPM). The illustration shows two of several substrates (14) attached to the underside of the rotating disk. The substrates are attached at their edges, so that most of the undersides of the substrates are exposed to the vapor below. The entire apparatus is enclosed in a chamber kept at low pressure by a vacuum pump. Magnesium diboride (MgB2) is an ionic solid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (electronics)
In electronics, a wafer (also called a slice or substrate) is a thin slice of semiconductor, such as a crystalline silicon (c-Si), used for the fabrication of integrated circuits and, in photovoltaics, to manufacture solar cells. The wafer serves as the substrate for microelectronic devices built in and upon the wafer. It undergoes many microfabrication processes, such as doping, ion implantation, etching, thin-film deposition of various materials, and photolithographic patterning. Finally, the individual microcircuits are separated by wafer dicing and packaged as an integrated circuit. History In the semiconductor or silicon wafer industry, the term wafer appeared in the 1950s to describe a thin round slice of semiconductor material, typically germanium or silicon. Round shape comes from single-crystal ingots usually produced using the Czochralski method. Silicon wafers were first introduced in the 1940s. By 1960, silicon wafers were being manufactured in the U.S. by c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
