this invention discloses a semiconductor power device disposed in a semiconductor substrate including an active cell areas and a termination area . the semiconductor power device further comprises a plurality of gate trenches formed at a top portion of the semiconductor substrate in the active cell area wherein each of the gate trenches is partially filled with a conductive gate material with a top portion of the trenches filled by a high density plasma insulation layer . the semiconductor power device further comprises mesa areas of the semiconductor substrate disposed between the gate trenches wherein the mesa areas are recessed and having a top mesa surface disposed vertically below a top surface of the hdp insulation layer wherein the hdp insulation layer covering over the conductive gate material constituting a stick - out boundary - defining layer surrounding the recessed mesa areas in the active cell areas between the gate trenches .