Reproducible liquid phase epitaxial growth of InGaAsP buried heterostructure lasers.

Lasers are formed using planar layers grown by hydride vapor phase epitaxy, which are masked and etched to define laser mesas, with final regrowth by liquid phase epitaxy. Controlled melt-etching of the exposed wafer surface is introduced just prior to the liquid phase epitaxial regrowth to form etched mesa buried heterostructure lasers. The melt etching uses an In-InP melt undersaturated by only ~0.2C and does not degrade the dimensional shape of the etched mesas. This process is shown to dramatically improve the growth reproducibility and results in excellent device characteristics. This closely controlled removal of the mesa sidewall just prior to epitaxy is also expected to contribute to increased laser reliability.