LDMOS (Laterally Diffused Metal Oxide Semiconductor) transistor and manufacturing method thereof

Abstract

The invention provides an LDMOS (Laterally Diffused Metal Oxide Semiconductor) transistor and a manufacturing method thereof. A plurality of STI (Shallow Trench Isolation) structures are arranged between a source region and a drain region, so that the breakdown voltage of the transistor is improved, and the problem that the central region of the bottom of the STI structure protrudes when the width of the STI structure broadens; based on the existing manufacturing process of the LDMOS transistor, the additional manufacturing process of the LDMOS transistor provided by the invention is not added, so that the degree of complexity of manufacturing is reduced; after the plurality of STI structures are formed, the subsequent manufacturing process does not need to be changed, so that the possibility of impact on certain characteristics of other devices positioned on the same semiconductor substrate is avoided; and the impact on some characteristics of the transistor itself is also avoided.

Description

technical field [0001] The invention relates to the field of double diffused metal oxide semiconductors (DMOS), in particular to an LDOMS transistor and a manufacturing method thereof. Background technique [0002] In power applications, since DMOS (double-diffused metal-oxide-semiconductor) technology adopts a vertical device structure (such as a vertical NPN bipolar transistor), it has many advantages, including high current drive capability, low on-resistance and high breakdown Voltage, etc., the document of patent No. 200810103337 discloses a high voltage resistant DMOS transistor. There are two main types of DMOS transistors, vertical double-diffused metal oxide semiconductor field effect transistor VDMOSFET (vertical double-diffused MOSFET) and lateral double-diffused metal oxide semiconductor field effect transistor LDMOSFET (lateral double-dif fused MOSFET). Compared with common field effect transistors, LDMOS transistors have obvious advantages in key device charac...

AI Technical Summary

Problems solved by technology

However, in the actual production process, it will be found that such an approach cannot increase the breakdown voltage of the LDMOS transistor, and even in some cases such an approach will reduce the breakdown voltage of the LDMOS transistor.

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