The invention concerns a device for photodetection with a vertical metal semiconductor microresonator and procedure for the manufacture of this device.

According to the invention, in order to detect an incident light, at least one element is formed over an insulating layer that does not absorb this light, including a semiconductor material and at least two electrodes holding the element, with the element and electrode unit being suitable for absorbing this light and designed to increase the light intensity with respect to the incident light, in particular by making a surface plasmon mode resonate between the unit interfaces with the layer and the propagation medium for the incident light, with the resonance of this mode taking place in the interface between the element and at least one of the electrodes, with this mode being excited by the component of the magnetic field of the light, parallel to the electrodes. Application for optical telecommunications.