Patent ID: 7868406

Claim:
A photodiode being monolithically integrated onto a waveguide, the photodiode comprising a substrate having a first side and an opposing second side, the waveguide consisting essentially of a layer from a semi-insulating material having a first side and an opposing second side, the first side being arranged in direct contact with a semi-insulating surface, wherein the layer constituting the waveguide has a first refractive index, an electroconductive n-contact layer having a first side and an opposing second side, wherein the first side of the electroconductive n-contact layer is located on the second side of the waveguide, the n-contact layer having a second refractive index, an absorption layer having a first side and an opposing second side, wherein the first side of the absorption layer is arranged on the second side of the electroconductive n-contact layer, at least one p-contact layer having a first side and an opposing second side, wherein the first side of the p-contact layer is arranged on the second side of the absorption layer, wherein the second refractive index of the n-contact layer is larger than the first refractive index of the semi-insulating waveguide layer, and wherein the n-contact layer is elongated in the direction of the waveguide by a length L compared to the absorption layer and the p-contact layer.