Anisotropic reactive ion etching of InP in methane/hyclrogen based plasmas

Abstract

We have investigated reactive ion etching of InP in methane/hydrogen based plasmas. We have determined mask systems and etch chemistries for low roughness anisotropic etching of photonic device structures. Methane/hydrogen mixtures have been known to etch InP, however the simultaneous deposition of carbon containing polymer, surface roughness and lack of reliable rate control has limited their utility.1 We have carefully examined the role of etching conditions and chemistries to optimize the rate and anisotropy and to understand and control the polymer deposition in methane/hydrogen based etching. Part of the investigation included empirical modeling of the etch process.2 We have also studied the inclusion of oxygen in the etch gas for enhanced results.