US 5,308,784 A · Semiconductor device and method for making the same

Abstract

There is disclosed in the present invention a method for manufacturing a semiconductor device including an isolation region defined by trenches having different or equal widths respectively on a single semiconductor substrate comprising the steps of: forming insulating films on the semiconductor substrate and then forming an aperture on a passive region (isolation region); forming spacers of etch rate different from that of the insulating films on sidewalls of the aperture to define ring-shaped trench regions surrounding outline of active regions; forming another insulating film of etch rate different from that of the spacers on the substrate where the spacers are defined and removing the spacers by etching to expose the substrate within the etched spacers; and forming trenches on the exposed area of the substrate, forming an insulating film of equal character to that of the insulating films used at the time of the formation of the aperture to refill the trenches and forming the spacers on the sidewalls of the insulating film in the passive region, thereby forming ring-shaped trenches surrounding the outlines of the active regions to be an isolation region.

Claims11

Dependent claims

A method of making a semiconductor device comprising the step of

forming at least one layer of an insulating film on a surface of a semi-conductor substrate;
removing portions of said insulating film from said surface of the substrate to form a plurality of passive regions exposing said surface and a plurality of active regions with said insulating film thereon;
forming a pair of spacers of an etch rate different from the etch rate of said insulating film on said substrate surface and on opposite sides of at least one passive region;
forming a second layer of an insulating film on at least said surface of said substrate between said pair of spacers, said second layer having an etch rate different from said etch rate of said spacers;
etching said spacers from said substrate to expose said substrate surface thereat;
removing portions of the exposed substrate to form a pair of trenches in said substrate on opposite sides of said one passive region;
forming a third layer of a high-temperature insulating film over the remaining portions of said one layer, the remaining portions of said second layer of insulating film and each passive region while filling each trench with the material of said third layer;
and
thereafter etching the high-temperature film and remaining portions of said one layer from the substrate to expose said active regions while retaining said remaining portions of said second layer and while retaining the material in said trenches as spacers in each passive region.

6 more elements

Dependencies are inferred from the claim text.

Semiconductor device and method for making the same

Life of this patent

Semiconductor device and method for making the same

Life of this patent

Abstract

Claims11