Epitaxy is one of a portfolio of wafer processing technologies for which we provide equipment. The word comes from the Greek epi meaning "above", and taxis meaning "in an ordered manner". It involves the deposition of silicon or silicon compounds to form layers that help to continue and perfect the crystal structure of the bare silicon wafer below. Epitaxy improves the electrical characteristics of the wafer surface, making it suitable for highly complex microprocessors and memory devices. Selective Epitaxy is an Epitaxy process that only deposits silicon or a silicon compound on certain predetermined areas of the wafer.
WHAT HAPPENS DURING EPITAXY?
Epitaxial layers are deposited selectively to form the transistor channel region, as well as the source and drain. The source is the point where charge carriers like electrons enter the channel, and the drain is where they leave. Between them is the gate that controls the conductivity of the channel. It can be switched to allow electrons to flow or to prevent them from flowing. By combining additional elements in the processing source gases, manufacturers can dope Epitaxy films to very precise concentrations of the dopant elements.
Epitaxy improves the electrical characteristics of the wafer surface in a highly controlled manner, making it suitable for highly complex microprocessors and memory devices.