Manufacturing method capable of improving plane VDMOS gate-oxide breakdown

Abstract

The invention discloses a manufacturing method capable of improving plane VDMOS gate-oxide breakdown. The method is characterized in that the method comprises an epitaxial layer, a well region, a source region, a gate oxygen layer, a polycrystalline layer, a polycrystalline shape-preserving dielectric layer, a dielectric layer and a metal layer. The method comprises the following steps: 1) formingthe epitaxial layer through a conventional method; 2) preparing the well region and the source region; 3) carrying out deposition of the gate oxygen layer; 4) carrying out polycrystalline layer deposition and doping; 5) carrying out polycrystalline lithography; 6) forming the polycrystalline shape-preserving dielectric layer through a mode of low-temperature LPCVD of SiO2, wherein the thickness of the polycrystalline shape-preserving dielectric layer is 10nm-60nm; 7) carrying out deposition of the dielectric layer through a conventional method; 8) carrying out hole lithography etching and interconnection metal sputtering; and 9) carrying out interconnection metal lithography and alloy.

Description

technical field [0001] The invention relates to the field of semiconductor power devices, in particular to a manufacturing method for improving planar VDMOS gate oxide breakdown. Background technique [0002] Vertical double-diffusion power MOSFET (VDMOS: Vertical Double-diffusion Metal Oxide Semiconductor) device is widely used in motor speed regulation and inverter due to its advantages of low power consumption, fast switching speed, strong driving capability, and negative temperature coefficient. , electronic switches, automotive electrical appliances and electronic ballasts, etc., are one of the core components of power integrated circuits and power integrated systems. [0003] As the gate oxide process at the core of MOS devices, it plays a vital role in the key parameters and long-term reliability of the device. The deterioration of gate oxide quality will lead to problems such as threshold voltage shift and gate leakage increase. With the reduction of process size, t...

AI Technical Summary

Problems solved by technology

Based on the characteristics of the planar VDMOS process, although the conventional polysilicon oxidation process or annealing treatment with oxygen atmosphere avoids the problem of impurity precipitation in the high-temperature process of heavily doped polysilicon, it leads to the reduction of gate oxide breakdown.

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