Multiphysics simulation for the optimisation of CMOS processes for high precision optical measurement applications

During the last years complementary metal oxide semiconductor (CMOS) technologies found widespread use in the fabrication of optical sensors and imagers.1-3 However, during the development of CMOS photodiodes for special high precision applications like spectroscopy various aspects have to be considered that are negligible for photodiodes employed in common imaging applications.4 Using two approaches, each combining optical simulations of the impinging radiation with electrical simulations of the generated charge carriers, an improved photodiode design for spectroscopy applications is studied in terms of spectral sensitivity as well as optical and electrical crosstalk. It will be demonstrated how the proper combination of these two approaches leads to an efficient development of the improved photodiode design prior to the first fabrication activities, which is important due to the huge effort, both in cost and time, that is involved in CMOS fabrication.