Silicon power semiconductors

Power recovery, 20 139-143 Power recovery expander, 22 731 Power recovery systems process flow in, 22 730-731 types of, 22 729-730 PowerSearch software, 28 244, 250 Power semiconductors silicon-based, 22 260-261 silicon carbide in, 22 539-540 Power station design, 20 757 Power supplies... 

Due to their tailorable combinations of properties, MMCs may play a key role in advanced electronic packaging, e.g., in power semiconductor diodes. In this application, the silicon wafer cannot be directly soldered to the copper electrode, due to a DIE mismatch (a (Si) = 4.1 X 10 a (Cu) = 17 x 10 C ). Under service conditions, interface delamination would occur as the result of thermal stresses arising from temperature changes. In conventional power diodes, the problem is partly solved by using an intermediate molybdenum or tungsten layer with a CTE between those of silicon and copper (a (Mo) = 5.0 x 10 ° and a (W) = 4.6 x 10 °C ). Another concept is the use a carbon fiber reinforced copper electrode. Carbon fibers have negative CTEs with a CTE matching that of Si [50]. 

Imamura, H., Kikuchi, H., and Watanabe, J., Silicon Nitride (Si3N4) Substrates for Power Semiconductor Modules, Presented at IMAPS New England, May 6, 2004. 

A variety of noncorrosive, thermaUy conductive silicone adhesives are available that are suitable for use in bonding hybrid circuit substrates, connecting power semiconductor components and devices to heat sinks as well as for use in other bonding applications requiring thermal conductivity. The flowable versions are used as thermally conductive potting materials for transformers, power supplies, coils, and other electronic devices that require improved thermal dissipation [41]. 

Silicon is the most popular material for photovoltaic (PV) power. Another material is gallium arsenide (GaAs), which is a compound semiconductor. GaAs has a crystal structure similar to that of silicon, but it consists of alternating gallium and arsenic atoms. It is well suited for PV applications since it has a high light absorption coefficient and only a thin layer of material is required, which reduces the cost. 

Casady, J. B., et al., Silicon Carbide Power MOSFET Technology, IEEE Inti. Symposium on Compound Semiconductors, September 8-11, 1997, pp. 359-362. 

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