Enabling low-cost QCL by large scale fabrication on CMOS pilot line

The costs of manufacturing QCL are still a major bottleneck for the adoption of this technology for chemical sensing. The integration of MIR sources on Si substrate based on CMOS technology paves the way for high-volume low-cost fabrication. Furthermore, the use of Si-based fabrication platform open the way to the co-integration of QCL MIR sources with Si-based waveguides, allowing realization optical sensors fully integrated on planar substrate. We report the fabrication of DFB QCL sources operating at 7.4μm on silicon substrate within 200 mm CMOS/MEMS pilot line. To do so, we have developed an appropriate fabrication process flow that fully respects the design and the process rules of a standard CMOS manufacturing line. Moreover, we have developed wafer level electro-optic characterization on prober station. The characterizations done at wafer level on thousands devices have demonstrated average threshold current densities close to between 3 kA/cm2 and 2.5 kA/cm2 with a relative dispersion around 5%. The optical power can reach 1 mW at ambient temperature, 1.5% duty cycle. This fabrication run achieves performance at the state of the art, that are comparable with those of QCL fabricated on InP substrate. With a yield of 98% on the wafer central fields, this work give perspectives to address application fields needing low cost MIR laser sources.