SiGe Semi chip serves GPS, Galileo

What is a semiconductor?
A class of materials, for instance silicon and germanium, whose electrical properties lie between those of conductors (such as copper and aluminum) and insulators (such as glass and rubber). It displays relatively high resistance in pure state and much lower resistance when it contains small amounts of certain impurities.

What is SiGe?
SiGe (silicon-germanium) is the alloy of silicon and germanium. Germanium is very similar to silicon, but when one layer is grown on top of the other to form the base of the transistor, the resulting transistor can switch faster and yield higher performance. SiGe is commonly used in the semiconductor industry, where it is employed for producing heterojunction bipolar transistors or as a strain-inducing layer for CMOS transistors.