Patent ID: 6995386

Claim:
A fluorescence detecting device comprising: a semiconductor integrated circuit substrate including a plurality of photodiodes and a signal detecting circuit for detecting charges obtained as a result of photoelectric conversion by the plurality of photodiodes; and a fluorescence reaction vessel where a fluorescence reaction occurs, the fluorescence reaction vessel being formed on the plurality of the photodiodes, with a plurality of photodiodes provided per one fluorescence reaction vessel; wherein the fluorescence reaction in the one fluorescence reaction vessel generates fluorescence that enters the plurality of photodiodes and is subjected to the photoelectric conversion, and wherein an excitation-light-entry preventing layer is formed at either or both of a surface portion of the plurality of photodiodes and a position between the plurality of photodiodes and the fluorescence reaction vessel; wherein the photodiodes include a high concentration first-conductivity-type semiconductor layer, a second-conductivity-type semiconductor layer, and a low-concentration first-conductivity-type semiconductor layer that are laminated in the stated order from a surface side of the photodiodes, wherein when a reverse bias is applied, a part of the high-concentration first-conductivity- type semiconductor layer is not depleted, and the second-conductivity-type semiconductor layer is depleted, and the high-concentration first-conductivity-type semiconductor layer constitutes the excitation-light-entry preventing layer.