The invention discloses a semiconductor manufacture method comprising the following steps of forming a first oxide layer on the side wall of a control grid; forming insulation layers on both sides of the first oxide layer; forming second oxide layers on both sides of each insulation layer; removing the second oxide layers by etching; and forming self-aligning silicide on semiconductor substrates on both sides of each insulation layer and the control grid. The invention increases the insulation thickness of the second oxide layers and nitride by forming the second oxide layers and the nitride so as to avoid excessively etching the first oxide layer because of too high etching speed in the process of etching the second oxide layers and prevent the self-aligning silicide from spreading to the control grid when forming the self-aligning silicide. Thus, the control grid is prevented from passing through the self-aligning silicide and the occurrence of electricity leakage between a source electrode and a drain electrode is avoided so that the performance of devices can be improved.