New generation of enhanced performance SPAD devices focused on NIR

27-11-2023 | X-FAB | Semiconductors

X-FAB Silicon Foundries SE has introduced a specific NIR version to its SPAD device portfolio. Like the previous SPAD generation launched in 2021, this version is based on the company’s 180nm XH018 process. Including an extra step to the fabrication, the workflow has produced notable increases in signal while still retaining the same low noise floor without negatively affecting parameters such as dark count rate, afterpulsing and breakdown voltage.

Through this latest variant, the company is successfully expanding the scope of its SPAD offering, enhancing its ability to address multiple emerging applications where NIR operation proves critically important. Among these are ToF sensing in industrial applications, vehicle LiDAR imaging, biophotonics and FLIM research work, and various medical-related activities. Sensitivity is increased over the whole NIR band, with respective improvements of 40% and 35% at the key wavelengths of 850nm and 905nm.

The new SPAD devices will reduce the complexity of visible light filtering since UV and visible light are already suppressed. Filter designs will, therefore, be simpler, with fewer component parts involved. Furthermore, having the same footprint dimensions as the previous SPAD generation supplies a straightforward upgrade route. Customers’ existing designs can gain major performance benefits by swapping in the new devices.

The company has compiled a comprehensive PDK for the NIR SPAD variant, with extensive documentation and application notes featured. Models for optical and electrical simulation will provide engineers with the additional design support they need, enabling them to integrate these devices into their circuitry quickly.

As Heming Wei, product marketing manager sensors at X-FAB, explains, “Our SPAD technology has already gained a very positive market response, seeing uptake with a multitude of customers. Thanks to continuing innovation at the process level, we have now been able to develop a solution that will secure business for us within various NIR applications across automotive, healthcare and life sciences.”

By Seb Springall