US 2002/0162571 A1 · Planar clean method applicable to shallow trench isolation

Abstract

The present invention provides a planar clean method applicable to shallow trench isolation (STI) for cleaning a substrate having a STI region formed thereon and a high density plasma (HDP) oxide on the surface of the STI region. A buffer oxide etch cleaning solution is exploited and matched by a planar clean way to let the oxide losses of the surface of the silicon substrate and the STI corners match the height and shape of the HDP oxide in the STI region. Thereby, the phenomenon of wrap rounding at the STI corners, which influences growth of the next thermal oxide, can be avoided. The present invention can prevent the STI corners from generating parasitic device characteristics and enhance electric characteristics of the device.

Claims4

Dependent claims

A planar clean method applicable to shallow trench isolation, a shallow trench isolation region being formed on a substrate, a high density plasma oxide being deposited on a surface of said shallow trench isolation region, said high density plasma oxide covering corners of said shallow trench isolation region, said clean method comprising the steps of:

providing a buffer oxide etch cleaning solution;
and
letting said buffer oxide etch cleaning solution levelly and uniformly flow over surfaces of said substrate and said high density plasma oxide to perform the cleaning action.

Dependencies are inferred from the claim text.

Facts

Application

09/846,184Filed 2 May 2001

Published

7 Nov 2002

Term ends

Not estimatedThe source records don’t support an estimate.

Classification8 codes

H10P 95/064
Involving a dielectric removal step: the removal being chemical etching
B08B 3/08
Cleaning involving contact with liquid: the liquid having chemical or dissolving effect
H10W 10/014
Of isolation regions comprising dielectric materials: using trench refilling with dielectric materials, e.g. shallow trench isolations
H10W 10/17
Isolation regions comprising dielectric materials: formed using trench refilling with dielectric materials, e.g. shallow trench isolations

Planar clean method applicable to shallow trench isolation

Life of this patent

Planar clean method applicable to shallow trench isolation

Life of this patent

Abstract

Claims4