METHOD FOR FORMING SPLIT GATE ELECTRODE OF NVM DEVICE TO MAKE GATE OXIDE LAYER UNDER CONTROL GATE OF SPLIT GATE ELECTRODE HAVE WITHSTAND VOLTAGE WITH RESPECT TO HIGH VOLTAGE APPLIED TO CONTROL GATE AND MAKE OXIDE LAYER IN CONTACT WITH CONTROL GATE SIDEWALL SMOOTHEN TUNNELING EFFECT OF ELECTRONS

摘要

Purpose: a kind of method is used to form under a control door of the gate electrode that a gate electrode device to split of a NVM (nonvolatile memory) splits one and is arranged to manufacture a gate oxide and has the one of the high voltage for being applied to control door relative to one to be subjected to voltage and with a control door side wall contact manufacture oxide layer by making oxide skin(coating) be present between control door and a floating gate tunnel-effect of smooth electronics and under control door with different thicknesses. Construction: after the nitride layer, white layer mode for selectively exposing a polysilicon layer is formed, the spacer oxide layer with a uniform thickness is formed. One etch-back process will carry out forming a gasket, and a polysilicon layer mode split and a power supply line are formed in the opening of nitride layer, white layer mode. After the polysilicon layer mode of exposed nitride layer, white layer mode and exposure is etched to form the floating gate that one splits, gate oxide, which is present in the floating gate to split other than a region and is etched away to an once substrate (100), to be not exposed. The second gate oxide with a uniform thickness is formed in composite structure.