Modified clean chemistry and megasonic nozzle for removing backside CMP slurries
AssigneeTexas Instruments Incorporated
InventorsChangfeng Xia, Linlin Chen
Life of this patent
Estimating the term…
Abstract
A cleaning chemistry for lowering defect levels on the backside of a semiconductor wafer after chemical mechanical planarization (CMP). In a preferred embodiment of the present invention, a cleaning chemistry comprising nitric acid, hydrofluoric acid, and phosphoric acid in solution with deionized water is applied to the wafer surface to be cleaned preferably while subjected to megasonic assist cleaning. The wafer is preferably then subjected to brush scrubbing and a deionized water rinse with megasonic assist cleaning.
Claims17
A method for removing particulate defects from a semiconductor wafer backside comprising the steps of applying an aqueous cleaning solution consisting essentially of 10 to about 40 weight percent of nitric acid (HNO3), 2 to about 15 weight percent of hydrofluoric acid (HF), and 5 to about 20 weight percent of phosphoric acid (H3PO4 to the semiconductor wafer backside wherein the particulate defects are metal particles and slurry particles comprising silica or alumina.
Dependencies are inferred from the claim text.