A photodetector for the detection of a light beam, comprising: ∘ a substrate layer and two adjacent layer stacks mounted on the substrate layer, ∘ wherein a first layer stack comprises ∘ a metal layer acting as a ground plane, ∘ a semiconductor layer covering the metal layer, wherein the semiconductor layer is made of at least two different materials forming an heterostructure adapted for generating a detection current by absorbing the light beam bringing electrons from a fundamental state to an excited state, the thickness of the semiconductor layer being inferior to a wavelength of the light beam to be detected, ∘ an array of metal pads and metal connection strips covering the semiconductor layer collecting the light beam and directing it towards the semiconductor layer, each of the metal pads, together with the semiconductor layer and the metal layer underneath it, forming a vertical cavity type resonator, the metal pads being interconnected by the metal connection strips for conducting the detection current, wherein the semiconductor layer is completely etched in the areas of the semiconductor layer that are neither covered by the metal pads nor by the connection strips, and wherein each metal pad is forming an antenna for collecting incident photons of the light beam on an effective collection surface (Σ') of the light at least twice larger than a physical collection surface of the semiconductor layer covered by said metal pad, characterized in that ∘ a second layer stack comprises: ∘ an insulating layer and ∘ a patch antenna, said patch antenna being planar and disposed on said insulating layer, and facing at least one metal pad so as to focus incident photons on the vertical cavity type resonator, and wherein at least one metal pad is connected to the patch antenna and the ground plane is a strip metal layer. ∘ a substrate layer and two adjacent layer stacks mounted on the substrate layer, ∘ wherein a first layer stack comprises ∘ a metal layer acting as a ground plane, ∘ a semiconductor layer covering the metal layer, wherein the semiconductor layer is made of at least two different materials forming an heterostructure adapted for generating a detection current by absorbing the light beam bringing electrons from a fundamental state to an excited state, the thickness of the semiconductor layer being inferior to a wavelength of the light beam to be detected, ∘ an array of metal pads and metal connection strips covering the semiconductor layer collecting the light beam and directing it towards the semiconductor layer, each of the metal pads, together with the semiconductor layer and the metal layer underneath it, forming a vertical cavity type resonator, the metal pads being interconnected by the metal connection strips for conducting the detection current, wherein the semiconductor layer is completely etched in the areas of the semiconductor layer that are neither covered by the metal pads nor by the connection strips, and wherein each metal pad is forming an antenna for collecting incident photons of the light beam on an effective collection surface (Σ') of the light at least twice larger than a physical collection surface of the semiconductor layer covered by said metal pad, characterized in that ∘ a second layer stack comprises: ∘ an insulating layer and ∘ a patch antenna, said patch antenna being planar and disposed on said insulating layer, and facing at least one metal pad so as to focus incident photons on the vertical cavity type resonator, and wherein at least one metal pad is connected to the patch antenna and the ground plane is a strip metal layer. ∘ a metal layer acting as a ground plane, ∘ a semiconductor layer covering the metal layer, wherein the semiconductor layer is made of at least two different materials forming an heterostructure adapted for generating a detection current by absorbing the light beam bringing electrons from a fundamental state to an excited state, the thickness of the semiconductor layer being inferior to a wavelength of the light beam to be detected, ∘ an array of metal pads and metal connection strips covering the semiconductor layer collecting the light beam and directing it towards the semiconductor layer, each of the metal pads, together with the semiconductor layer and the metal layer underneath it, forming a vertical cavity type resonator, the metal pads being interconnected by the metal connection strips for conducting the detection current, wherein the semiconductor layer is completely etched in the areas of the semiconductor layer that are neither covered by the metal pads nor by the connection strips, and wherein each metal pad is forming an antenna for collecting incident photons of the light beam on an effective collection surface (Σ') of the light at least twice larger than a physical collection surface of the semiconductor layer covered by said metal pad, characterized in that ∘ a second layer stack comprises: ∘ an insulating layer and ∘ a patch antenna, said patch antenna being planar and disposed on said insulating layer, and facing at least one metal pad so as to focus incident photons on the vertical cavity type resonator, and wherein at least one metal pad is connected to the patch antenna and the ground plane is a strip metal layer. ∘ an insulating layer and ∘ a patch antenna, said patch antenna being planar and disposed on said insulating layer, and facing at least one metal pad so as to focus incident photons on the vertical cavity type resonator, and wherein at least one metal pad is connected to the patch antenna and the ground plane is a strip metal layer.