Chlorine-based dry etching of III/V compound semiconductors for optoelectronic application

Chlorine-based dry etching of III/V compound semiconductors for optoelectronic applications has been reviewed. The advantages of the ultrahigh-vacuum (UHV)-based electron cyclotron resonance (ECR)-plasma reactive ion beam etching (RIBE) over conventional RF-plasma reactive ion etching (RIE) were emphasized as the capability to use carbon-free, chlorine (Cl-2) gas plasmas, controllability of ion energies and compatibility with other UHV-based chambers such as a molecular beam epitaxy (MBE) chamber. The RIBE technique was shown to exhibit excellent laser diode performances, such as extremely low threshold-current, high polarization-controllability and a lifetime of more than 3000 h for structures with more than 1-mu m-wide etched-mesa width. The degree of etching-induced damage was evaluated in terms of the nonradiative surface recombination velocity S-r and the possibilities of practical applications of the dry-etched devices were discussed using the S-r values.