Preparation method of semiconductor device

Abstract

The invention provides a preparation method of a semiconductor device. The method comprises the steps of providing a semiconductor substrate, wherein a grid electrode, a source electrode and a drain electrode are formed on the semiconductor substrate; forming an interlayer dielectric layer on the semiconductor substrate, and etching the interlayer dielectric layer to form contact holes, wherein the contact hole communicated with the drain electrode is in a strip shape, at least part of the drain electrode is continuously exposed, the contact hole communicated with the grid electrode and the source electrode is in a dot shape, and at least part of the grid electrode and the source electrode are discontinuously exposed; and obliquely injecting ions into the interlayer dielectric layer so asto ensure that the ions in at least one direction are injected into the drain electrode through the contact hole to form an ion injection region. According to the invention, ion injection is carried out through contact holes in an interlayer dielectric layer to realize ESD protection, and compared with the prior art in which a yellow light defined ion implantation region is firstly made on the drain before the interlayer dielectric layer, the method of the inventionreduces a one-step photomask process, saves the process cost, and is simple and easy to implement.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a method for preparing a semiconductor device. Background technique [0002] As semiconductor device technology continues to enter submicron and deep submicron, the reliability of ESD (electrostatic discharge) protection devices becomes more and more important. For MOS devices used as ESD protection, in order to achieve the purpose of internal circuit protection, the breakdown voltage of MOS devices used as ESD protection is often required to be slightly lower than the protected device, and the series resistance of the drain region is higher than that of the protected device. In order to achieve this goal, the method of increasing ion implantation (ESD implant) in the drain area is often used to reduce the breakdown voltage of the ESD device, but increasing the ion implantation in the drain area requires an additional mask, thus increasing the manufacturing co...

AI Technical Summary

Problems solved by technology

In order to achieve this goal, the method of increasing ion implantation (ESD implant) in the drain area is often used to reduce the breakdown voltage of the ESD device, but increasing the ion implantation in the drain area requires an additional mask, thus increasing the manufacturing cost

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