epiwafer

An epiwafer is a wafer of semiconducting material made by epitaxial growth (called epitaxy) for use in making microelectronic devices such as light-emitting diodes (LEDs). Two methods of growing the epitaxial layer on existing silicon or other wafers are currently used: metal organic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE).

These wafers are typically newer types of semiconductors such as gallium nitride (GaN), or some combination of the elements gallium, indium, aluminum, nitrogen, phosphorus or arsenic.