Smooth and Vertical-Sidewall InP Etching Using CL sub 2/N sub 2 Inductively Coupled Plasms

Inductively-coupled plasma operated in the reactive-ion etching mode (ICP-RIE) is used for mesa etching of InP using Cl sub 2/N sub 2 chemistry with a Ni metal mask. Etch rate of approximately 140nm/min with very smooth and vertical sidewalls is obtained at a DC bias of 120V. The effects of temperature, gas flow, chamber pressure, ICP source power and substrate bias power on etch rate; sidewall profile and surface morphology will be discussed.