Laterally double diffused metal oxide semiconductor transistor and manufacturing method thereof

Abstract

The invention provides a laterally double diffused metal oxide semiconductor (LDMOS) transistor and a manufacturing method thereof. In one embodiment of the invention, LDMOS transistor comprises (1) n doping deep n well area (DNW) on a substrate, (2) a gate oxide and a drain oxide between a source electrode area and a drain electrode area, wherein the gate oxide is adjacent to the source electrode area and the drain oxide is adjacent to drain electrode area, (3) conductive gate on the gate oxide and part of drain oxide, (4) p-doped p-body area in the source electrode area, (5) n-doped area inthe drain electrode area, (6) a first n-doped n+ area and p-doped p+ area in the p-doped p-body area of the drain electrode area, wherein the first n-doped n+ area is adjacent to the p-doped p+ area,(7) a second n-doped n+ area in the drain electrode area.

Description

technical field [0001] The invention relates to the field of semiconductor devices, in particular to a lateral double-diffused metal oxide semiconductor (LDMOS) transistor and a manufacturing method thereof. Background technique [0002] Voltage regulators, such as DC-DC voltage converters, are used to provide a stable voltage source for a wide variety of electronic device systems. Low-voltage devices (such as notebook computers, mobile phones, etc.) especially require high-efficiency DC-DC converters for battery management. A switching voltage regulator generates an output voltage by converting an input DC voltage to a high frequency voltage, which is then filtered to produce an output DC voltage. Specifically, a switching regulator includes a switch to alternately connect and disconnect an input DC voltage source (such as a battery) and a load (such as an integrated circuit). The output filter generally consists of an inductor and capacitor placed between the input volta...

AI Technical Summary

Problems solved by technology

[0004] The present invention provides a lateral double-diffused metal oxide semiconductor (LDMOS) transistor and its manufacturing method to solve the problem of the reliability of the discontinuity region between the thin gate oxide layer and the thick high voltage oxide layer in the prior art and the HV gate in the manufacturing process The field oxide layer (FOX) is thinned when the oxide layer is etched, which will have a negative impact on the field isolation area.

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