Raman spectroscopy is a powerful technique capable of identifying the chemical composition of substances through their fingerprint vibrational spectrum. However due to the extremely weak Raman signal strength commercial Raman systems are invariably too expensive (several 1000 to 10000 €) and also too bulky for consumer use.
We aspire to build the smallest and most lightweight Raman spectrometer in the world, with a target size of 5x10x1 mm3 and a weight of only 0.1 g. To realize this chip-scale proof-of-concept device, we will build upon key achievements of the ERC Advanced Grant InSpectra and use mature building blocks: a 785 nm laser source, a Si3N4 photonic integrated circuit (PIC) and a CMOS imager chip. By using a standard CMOS process toolset for fabricating the spectrometer, a cost-effective and high yield product can be guaranteed with a price level at least an order of magnitude lower than current commercial systems. The exceptional form factor of the spectrometer will generate a rich variety of innovative applications of Raman spectroscopy. A spectrometer this small can be implanted, incorporated in smartphones or smartwatches and fits into textiles, drones etc. While the potential applications are very broad, the application targeted in this PoC-project will be the monitoring of harmful chemicals or air pollutants for personal safety monitoring, both at work and at home.