Electro-optical detector for lab-on-chip applications
This paper presents the integration on the same glass substrate of an amorphous silicon photodiode and a diffused waveguide, to achieve an integrated evanescent waveguide sensor. Simulations performed with COMSOL Multiphysics show that the coupling efficiency between the waveguide and the photosensor is strongly affected by the presence of the passivation layer, and by thickness and refractive index of the transparent electrode of the photodiode. A first prototype has been fabricated using standard microelectronics techniques in a 6-masks process flow.