Belgian group unveils pb-free QD-based SWIR sensor
Imec and its partners (Ghent University, QustomDot BV, ChemStream BV and Ams Osram) in the Belgium-funded Q-COMIRSE project have presented a first of its kind prototype shortwave infrared image sensor with InAs quantum dot photodiodes.
The proof-of-concept sensor, tested on both glass and silicon substrates, is believed to be the first of its kind to produce successful 1390 nm imaging results.
While QDs are considered fragile in nature, careful selection of stack materials resulted in >300 hour air-stability, enabling fab manufacturing compatibility. In addition, the pixel architecture can readily be integrated with CMOS technology for image sensing applications, but also allows flat panel display integration.
Pawel Malinowski, Imec technology manager and domain lead imaging, emphasised the significance of this breakthrough: "The first generation of QD sensors was crucial for showcasing the possibilities of this flexible platform. We are now working towards a second generation that will serve as a crucial enabler for the masses - aiming at cost-efficient manufacturing in an environmentally friendly way. With major industry players looking into quantum dots, we are committed to further refine this semiconductor technology towards accessible, compact, multifunctional image sensors with new functionalities."
Stefano Guerrieri, engineering fellow at Ams Osram, added: "Replacing lead in colloidal quantum dots with a more environmentally friendly material was our key goal in Q-COMIRSE. Our remarkable development work with Flemish partners Imec, Ghent University, QustomDot and ChemStream paves the way toward a low-cost and Pb-free short-wave-infrared technology that, once mature for industrial products, could enable unprecedented applications in robotics, automotive, AR/VR and consumer electronics among others."
Pictured above: Proof-of-concept lead-free quantum dot photodiode integrated into a shortwave infrared optical sensor
