METHOD FOR FABRICATING TWO DIFFERENT KINDS OF MOSFET'S(METAL-OXIDE-SEMICONDUCTOR FIELD-EFFECT-TRANSISTORS) IN ONE CHIP

摘要

Purpose: after a trench process is performed, a kind of method is arranged to (the metal-oxide-semiconductor (MOS) field-effect-transistor) of two different types of MOSFET of manufacture for manufacture one DMOS (dmos structures) transistors by the gate oxide that is formed in a low pressure range and according to a high voltage region of each work electricity in monolithic. Construction: low pressure range and the high voltage region definition in the semi-conductive substrate (100) with a scheduled foundation structure. One insulating layer deposition is in semiconductor substrate. One bar ditch are formed in substrate by a scheduled photolithography process. After the first gate oxide (106) is formed in ditch, the first gate oxide in low pressure range is removed. After the second gate oxide (108) is formed in the ditch in low pressure range and high voltage region, polysilicon layer (110) is deposited, and the first recess process is performed. Insulating layer is eliminated. An one scheduled photolithography process and scheduled implantation process is performed on low pressure range and high voltage region is formed a body region (111). Second polysilicon layer (112) is deposited on composite structure.