| abstract |
The invention relates to a photodetector for infrared light radiation having a given wavelength (λ), including a stack of layers consisting of: a continuous layer ( 11 ) of a partially absorbent semiconductor material, which constitutes the photodetection area; a spacer layer ( 12 ) of a material that is transparent to said wavelength and has an index ne; and a structured metal mirror ( 13 ), the distance (g) between the top of said mirror and the semiconductor layer being less than (λ)/ne and the mirror surface having a profile corresponding to the periodic repetition, according to period (P), of a basic pattern defined by the alternating series of raised surfaces ( 131, 132 ) and slots ( 133, 134 ) having the widths (L 1 , L 2 ) and (L 3 , L 4 ), respectively, the widths (L 1 ) to (L 4 ) being such that none are equal to zero, and that the sum thereof is equal to P and at least L 1 ≠L 2 or L 3 ≠L 4 . |