Method for contact profile improvement

摘要

A method to produce a contact or via opening and filled metallurgy for CMOS or other integrated circuits is described. Semiconductor device structures are provided in and on a semiconductor substrate. An insulating layer structure is formed thereover comprising a first layer of tetraethoxysilane (TEOS), a second layer of borophospho-TEOS (BPTEOS), and a third layer of TEOS. A contact opening is etched through the insulating layer structure not covered by a mask to the semiconductor device structures to be electrically contacted wherein the profile of the contact opening is not vertical because the BPTEOS layer is etched. horizontally more than the first and third TEOS layers and wherein native oxide builds up on the sidewalls of the contact opening. The substrate is dipped into a hydrofluoric acid solution to remove the native oxide on the sidewalls of the contact opening whereby the hydrofluoric acid etches the BPTEOS layer at a slower rate than it etches the first and third TEOS layers whereby the contact profile is made vertical. A glue layer is sputter deposited over the surface of the insulating layer structure and within the contact opening. A conducting layer is deposited over the glue layer filling the contact opening completing the electrical contact in the fabrication of the integrated circuit device.