Editing Reactive-ion etching (section)

== Equipment ==
A typical (parallel plate) RIE system consists of a cylindrical vacuum chamber, with a [[wafer (electronics)|wafer]] platter situated in the bottom portion of the chamber. The wafer platter is electrically isolated from the rest of the chamber.  Gas enters through small inlets in the top of the chamber, and exits to the [[vacuum pump]] system through the bottom. The types and amount of gas used vary depending upon the etch process; for instance, [[sulfur hexafluoride]] is commonly used for etching [[silicon]]. Gas pressure is typically maintained in a range between a few milli[[torr]] and a few hundred millitorr by adjusting gas flow rates and/or adjusting an exhaust orifice.

Other types of RIE systems exist, including [[inductively coupled plasma]] (ICP) RIE. In this type of system, the plasma is generated with a [[radio frequency]] (RF) powered [[magnetic field]]. Very high plasma densities can be achieved, though etch profiles tend to be more [[Isotropy|isotropic]].

A combination of parallel plate and inductively coupled plasma RIE is possible. In this system, the ICP is employed as a high density source of ions which increases the etch rate, whereas a separate RF bias is applied to the substrate (silicon wafer) to create directional [[Electric field|electric fields]] near the substrate to achieve more anisotropic etch profiles.<ref>{{Cite journal|date=2011-01-01|title=Large-area multicrystalline silicon solar cell fabrication using reactive ion etching (RIE)|url=https://www.sciencedirect.com/science/article/abs/pii/S0927024810001583|journal=Solar Energy Materials and Solar Cells|language=en|volume=95|issue=1|pages=2–6|doi=10.1016/j.solmat.2010.03.029|issn=0927-0248|last1=Yoo |first1=Jinsu |last2=Yu |first2=Gwonjong |last3=Yi |first3=Junsin |url-access=subscription}}</ref> The RF power given to the substrate is often a tunable parameter called 'platen power', and controls the energy of ions bombarding the surface.<ref name="Rawal Agarwal Sharma Sehgal 2008 pp. 244–250">{{cite journal | last=Rawal | first=D.S. | last2=Agarwal | first2=Vanita R. | last3=Sharma | first3=H.S. | last4=Sehgal | first4=B.K. | last5=Muralidharan | first5=R. | title=A Reproducible High Etch Rate ICP Process for Etching of Via-Hole Grounds in 200μm Thick GaAs MMICs | journal=JSTS:Journal of Semiconductor Technology and Science | publisher=The Institute of Electronics Engineers of Korea | volume=8 | issue=3 | date=2008-09-30 | issn=1598-1657 | doi=10.5573/jsts.2008.8.3.244 | pages=244–250}}</ref>