Method of fabrication of a photonic chip comprising at least one photodiode of the SACM-APD type lying on a carrier substrate , and a waveguide extending parallel to the carrier substrate and optically coupled to the photodiode , comprising the following steps: ∘ formation of a contact portion made of a first semiconductor material doped according to a first type of conductivity, starting from a layer of the first semiconductor material lying on an insulating layer of the carrier substrate ; ∘ deposition of an encapsulation layer (12.1) covering the contact portion , and formation of a through-opening through the encapsulation layer (12.1) opening onto a surface of the contact portion ; ∘ formation, in the through-opening , of a multiplication portion made of the first semiconductor material starting from the surface of the contact portion , the multiplication portion having a thickness less than a height of the through-opening ; ∘ formation of a first spacer made of a first dielectric material, such that it covers the sides of the through-opening together with a peripheral part of constant width of a surface of the multiplication portion ; ∘ formation of a charge region in the multiplication portion and flush with an upper face of the latter, the charge region being bounded laterally by the first spacer such that it exhibits a constant peripheral recessing dr zc with respect to an edge of the multiplication portion ; ∘ formation of a second spacer made of a second dielectric material, distinct from the first dielectric material, such that it covers the first spacer together with a peripheral part of constant width of a surface of the charge region ; ∘ formation of an absorption portion made of a second semiconductor material, starting from a free surface of the charge region , the absorption portion being bounded laterally, at the interface with the charge region , by the second spacer such that its periphery is recessed by a constant amount dr pa with respect to an edge of the charge region . ∘ formation of a contact portion made of a first semiconductor material doped according to a first type of conductivity, starting from a layer of the first semiconductor material lying on an insulating layer of the carrier substrate ; ∘ deposition of an encapsulation layer (12.1) covering the contact portion , and formation of a through-opening through the encapsulation layer (12.1) opening onto a surface of the contact portion ; ∘ formation, in the through-opening , of a multiplication portion made of the first semiconductor material starting from the surface of the contact portion , the multiplication portion having a thickness less than a height of the through-opening ; ∘ formation of a first spacer made of a first dielectric material, such that it covers the sides of the through-opening together with a peripheral part of constant width of a surface of the multiplication portion ; ∘ formation of a charge region in the multiplication portion and flush with an upper face of the latter, the charge region being bounded laterally by the first spacer such that it exhibits a constant peripheral recessing dr zc with respect to an edge of the multiplication portion ; ∘ formation of a second spacer made of a second dielectric material, distinct from the first dielectric material, such that it covers the first spacer together with a peripheral part of constant width of a surface of the charge region ; ∘ formation of an absorption portion made of a second semiconductor material, starting from a free surface of the charge region , the absorption portion being bounded laterally, at the interface with the charge region , by the second spacer such that its periphery is recessed by a constant amount dr pa with respect to an edge of the charge region . <EOS>