Process of increasing screen dielectric thickness
AssigneeTexas Instruments Incorporated
InventorsSeetharaman Sridhar, Youngmin Kim, Zhiqiang Wu, Mark S. Rodder
Life of this patent
Estimating the term…
Abstract
A method of forming a semiconductor device using shallow trench isolation, includes forming a trench within a semiconductor substrate and forming a screen dielectric stack outwardly from the semiconductor substrate. The screen dielectric stack includes a first sacrificial dielectric layer disposed outwardly from the semiconductor substrate and a second sacrificial dielectric layer disposed outwardly from and in contact with the first sacrificial dielectric layer. In one embodiment, the first sacrificial dielectric layer is formed before forming the trench and the second sacrificial dielectric layer is formed after forming the trench.
Claims3
A method of manufacturing a semiconductor device using shallow trench isolation, comprising:
- forming a dielectric stack outwardly from a semiconductor substrate, the dielectric stack comprising:
- a first sacrificial dielectric layer disposed outwardly from the semiconductor substrate;
- and
- a second sacrificial dielectric layer disposed outwardly from the first sacrificial dielectric layer;
- wherein the first sacrificial dielectric layer is selectively etchable from the second sacrificial dielectric layer;
- removing a portion of the first sacrificial dielectric layer, a portion of the second sacrificial dielectric layer, and a portion of the substrate to form a trench within the semiconductor substrate and the dielectric stack;
- forming a first isolation dielectric region within the trench using thermal oxidation;
- forming a second isolation dielectric region on said first isolation dielectric region within the trench;
- removing the second sacrificial dielectric layer;
- and
- after removing the second sacrificial dielectric layer, depositing a dielectric material to form a third sacrificial dielectric layer outwardly from the first sacrificial dielectric layer, wherein a combined thickness of the first sacrificial dielectric layer and the third sacrificial dielectric layer comprises at least 100 Angstroms.
Dependencies are inferred from the claim text.