Facet passivation of GaAs semiconductor lasers using chemical and plasma methods

To remove the cavity surface contamination of semiconductor lasers and improve their COD threshold, the novel sulfur solution, acid pre-treatment plus sulfur solution and RF Ar plasma cleaning had been used on GaAs (100) substrate. The PL intensities after three types of processing increased by 30%, 42% and 33% respectively. With three methods used for laser process, we found that, in addition to acid pre-treatment, the COD threshold of lasers processed by other two methods have been improved greatly.