Abstract: In one embodiment, the disclosure relates to an electronic device successively comprising from its base to its surface: (a) a support layer, (b) a channel layer adapted to contain an electron gas, (c) a barrier layer and (d) at least one ohmic contact electrode formed by a superposition of metallic layers, a first layer of which is in contact with the barrier layer. The device is remarkable in that the barrier layer includes a contact region under the ohmic contact electrode(s). The contact region includes at least one metal selected from the metals forming the superposition of metallic layers. Furthermore, a local alloying binds the contact region and the first layer of the electrode(s).