Monolithic III-V microdisk lasers on silicon by template-assisted selective epitaxy

Abstract

In the present talk we discuss the application of Template-Assisted Selective Epitaxy (TASE) for the monolithic integration of III-V active photonic devices on silicon. The main concept of TASE relies on the guided growth of III-Vs within a confined oxide template. At one extremity of the template there is access to silicon to start the nucleation, and subsequently it is the template which guides the growth progression. This decoupling of the resulting geometry from the growth mode and substrate orientation, results in a larger processing window as we no longer rely on the growth conditions to tune the geometry, as well as a number of other advantages. A further unique advantage of TASE for silicon photonics applications is that it allows for the truly local integration of III-V material at precisely defined positions, since the location of the III-V may be defined with nm-scale precision in the same lithographic step as silicon passives. TASE was originally developed for electronics, but in recent years we have expanded it to enable several photonic devices. In the present talk, I will discuss our work on GaAs and InP microdisk lasers fabricated by either direct growth or via the use of micro-substrates. These devices show lasing at room temperature around 870 nm with thresholds of about 10 pJ/pulse. We also explore the use of metal-clad cavities for further light confinement.