Production method of high voltage MOS transistor

Abstract

A method for manufacturing a high-voltage MOS transistor, comprising the following steps: forming an auxiliary active region pattern to be exposed at the junction of an active region pattern to be exposed and an isolation region pattern to be exposed, and the auxiliary active region pattern to be exposed and the pattern to be exposed The pattern of the active region is connected to the pattern of the isolation region to be exposed; the pattern of the active region to be exposed, the pattern of the isolation region to be exposed and the pattern of the auxiliary active region to be exposed are transferred to the silicon substrate to form the active region, the isolation region and the auxiliary region. Active region; forming a gate oxide layer on the silicon substrate of the active region and the auxiliary active region; forming a polysilicon layer on the gate oxide layer; forming an opening pattern to be exposed in the gate pattern to be exposed; The pattern and the pattern of the opening to be exposed are transferred to the polysilicon layer to form a gate including an opening, the opening completely exposes the auxiliary active region, and the overlapping part of the gate and the active region is a channel. After the above steps, the bimodal phenomenon will not appear, thereby reducing the power consumption of the device and increasing the stability of the device operation.

Description

technical field [0001] The invention relates to a semiconductor manufacturing process, in particular to a method for manufacturing a high-voltage MOS transistor, in particular to a method for preventing double-peak effects in the process of manufacturing a high-voltage MOS transistor. Background technique [0002] In semiconductor technology, even though the device size continues to shrink, it is still desirable to improve the performance of transistors, and it is also desirable to manufacture integrated circuit semiconductor devices that combine low, high, and medium voltage applications. For example, integrated circuits (hereinafter referred to as driver ICs) used to drive image sensors, LCDs, and printed magnetic heads, etc., are composed of ICs with strong withstand voltage between the drain and source that operate at a power supply voltage above +V. The drive output unit of the high-voltage MOS transistor and the logic unit of the control drive output unit of the low-vo...

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Problems solved by technology

[0010] The problem to be solved by the present invention is to provide a method for manufacturing a semiconductor transistor, which prevents gate oxidation from being easily caused during the formation of the gate oxide layer due to the fact that the gate oxide layer of the high-voltage MOS transistor is relatively thick and is affected by the chamfering of the shallow trench isolation region. The edge part of the layer is thinner than the middle part, resulting in a lower threshold voltage at the edge of the gate oxide layer, resulting in a double peak phenomenon, resulting in high power consumption of the device and poor stability of the device.

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