KR930011159A - Device isolation structure of semiconductor device and manufacturing method thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a semiconductor device and a method of manufacturing the same. In particular, in a LOCOS device isolation method capable of minimizing side oxidation such as Buzzbee and side diffusion of impurities during an oxidation process of a field region, Patterning a buffer layer for protecting the active region and opening the field region; Performing a step of undercut etching the buffer oxide film of the buffer layer pattern inward after the step; Subsequently, a step of depositing a thin nitride film on the entire surface of the nitride, and then forming a spacer on the side wall of the thin nitride film with a material capable of stack expansion, and etching the nitride film using the spacer as a mask; Next, according to the present invention, a step of oxidizing the open field region is performed by undercut etching a predetermined amount of the underside of the buffer oxide layer under the buffer layer pattern to fill and block the thin nitride film in an inverted form of “T” to laterally oxidize the buffer oxide layer. The phenomenon of Buzzbeek can be almost completely removed, and the flatness of the field region can be improved as well as the spacer width by minimizing the lifting of the thin film by using the volume expansion of the spacer during the oxidation process of the Pilz region. Since the channel diffusion ions have a side diffusion margin, the channel blocking ion charges are limited within the field region, thereby greatly increasing the integration and electrical characteristics of the semiconductor autonomy.

Description

Device isolation structure of semiconductor device and manufacturing method thereof

Since this is an open matter, no full text was included.

3A through 3E are sectional views of a process for forming LOCOS device isolation by the method of the present invention.

Claims (10)

In the LOCOS device isolation region of a semiconductor device, a buffer layer is stacked in an active region on a silicon substrate so that a pad oxide film under a nitride film is undercut etching a predetermined amount into the active region, and a “T” character is formed on the axis of the buffer layer pattern axis. A structure of a semiconductor device, characterized in that a thin nitride film is placed in a reverse phase, and a spacer is provided on one side of the reverse phase of the letter “T” to open a field region. The structure of a semiconductor device according to claim 1, wherein the spacer is a material capable of stack expansion during the selective oxidation of the field region. 3. The structure of a semiconductor device according to claim 2, wherein the material capable of volume expansion is any one of polysilicon or a high temperature thermal oxide film. The structure of a semiconductor device according to claim 1 or 2, wherein said spacer is an ion implantation mask when implanting channel blocking ions into a silicon interface. A LOCOS device isolation method of a semiconductor device, comprising: patterning a buffer layer for protecting an active region on a substrate silicon to open a field region; Performing a step of undercut etching the buffer oxide film of the buffer layer pattern inward after the step; A process of depositing a thin nitride film on the entire surface of the resultant, followed by forming a spacer on the sidewall of the thin nitride film with a material capable of volume expansion, and etching the nitride thin film using the spacer as a mask; And subsequently oxidizing the open field region. The method of claim 5, wherein the buffer layer pattern is a pattern formed by sequentially stacking a buffer oxide film and a buffer nitride film to open a field region by a photolithography process. The method of claim 5, wherein the undercut process of the buffer oxide layer under the buffer layer pattern is a wet etching process using hydrofluoric acid (HF). The method of manufacturing a semiconductor device according to claim 5, wherein the undercut buffer oxide film portion is filled by a nitride film during a nitride film deposition process. The method of manufacturing a semiconductor device according to claim 5, wherein the spacer is made of any one of polysilicon and a high temperature thermal oxide film. The method of manufacturing a semiconductor device according to claim 5 or 9, wherein the space is formed by an entire surface etching back process in anisotropic etching. ※ Note: The disclosure is based on the initial application.