Suppressing recombination on silicon contact interfaces is a topic being addressed for various applications such as photo sensors and solar cells. Although salicidation of the contacts enables low contact resistance, it is usually avoided for these applications as it increases the recombination rate on the contact interfaces. This study explores the use of salicided polysilicon buffer layer in photodiodes' contacts, acting to reduce the recombination rate at the silicide contact. The contact incorporates the advantage of low contact resistance due to silicidation with polysilicon interface that reduces recombination by creating carrier selective junction. The introduction of a polysilicon interlayer was found to increase the short circuit current and the fill factor and to decrease the dark leakage current. The improvement in the light collection parameters was found to be more pronounced under high light intensity (1000 W/m2) than under low light intensity (400 W/m2). The benevolent effect of the polysilicon interlayer is expected to be noticed in devices that are sensitive to contacts' performance. This includes not only image sensors but also high efficiency silicon solar cells.
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