High performance self-organized InGaAs quantum dot lasers on silicon

Abstract

We report the molecular beam epitaxial growth and characteristics of room temperature InGaAs quantum dot lasers grown directly on silicon utilizing thin (⩽2μm) GaAs buffer layers and quantum dot layers as dislocation filters. Cross-sectional transmission electron microscopy studies show that defect-free quantum dot active regions can be achieved. Room temperature photoluminescence emission from quantum dots grown on silicon is comparable, in intensity and linewidth, to that from similar dots grown on GaAs substrates. The best devices are characterized by relatively low threshold current (Jth∼1100A∕cm2), high output power (>150mW), large characteristic temperature (T0=244K), and constant output slope efficiency (⩾0.3W∕A) in the temperature range of 5–95°C.