Abstract: The invention concerns a method for producing a field effect transistor having a trench gate comprising: —the forming (110) of at least one trench (11, 12, 13) in a semi-conductive substrate (1) having a first type of conductivity, said substrate comprising two opposing faces called front face and rear face, —the primary implantation (120) of ions having a second type of conductivity so as to implant each trench of the substrate to form an active gate area, —the depositing (160) of a layer of polycrystalline silicon having the second type of conductivity on the implanted active gate area, —the oxidation (160) of the layer of polycrystalline silicon, and —the metallization (180) of the substrate on the front and rear faces of same in order to form active source and drain areas.