A new silicon blue / UV selective stripe-shaped photodiode

摘要

A new silicon stripe-shaped photodiode for the selective detection of blue / UV light was realized in standard industrial 0.5μm CMOS technology, with a simple post-processing step. The selectivity is achieved using a shallow active region,limited by a high potential barrier at a depth of 450 nm. A stripe-shaped structure is used to minimize the dead layer area and thus enhance the UV sensitivity. The peak wavelength is at 440 nm. A ratio of the responsivities at 440 nm and 1μm better than 60 was achieved. An increase of the UV responsivity using our stripe-shaped photodiode by a factor 1.7 is predicted and demonstrated. This structure can be used in applications where low-cost blue / UV selective photodetectors are needed.