Back to results
US 5,472,902 AGranted
Silicon-on-insulator isolation technology using liquid phase deposition
AssigneeUnited Microelectronics Corp.
InventorWater Lur
Life of this patent
Estimating the term…
Abstract
A method of forming an isolated structure on a silicon substrate having a silicon-on-insulator (SOI) structure using liquid phase deposition which is capable of selectively depositing oxide only in trenches of the substrate. Recessed field oxides are grown with the same height and leave a flat surface on a top surface of the substrate. The liquid phase deposition is performed using saturated hydrofluosilicic acid as a reactant.
Claims8
A method of forming an isolated structure on a silicon substrate, comprising the following steps:
- (a) forming a buried insulating layer in said silicon substrate;
- (b) forming at least one trench having a bottom surface therein which at least meets the buried insulating layer in said silicon substrate;
- (c) forming a tungsten layer covering said silicon substrate except the bottom surface of said at least one trench;
- (d) subsequently depositing a field oxide to fill the resulting trench using liquid phase deposition;
- (e) removing the tungsten layer and thereby leaving at least one gap along a sidewall of said at least one trench;
- and
- (f) depositing a dielectric layer to fill said at least one gap.
4 more elements
Dependencies are inferred from the claim text.