Method of forming metal contact pads and terminals on semiconductor chips.

摘要

A method of forming metal contact terminals (35) of a determined size on a structure (23) of the type having an insulating substrate (17) with a metal land (18) formed thereon and a passivating layer (19) provided with an opening exposing a part of said metal land including the steps of: a) depositing chromium (28), copper (29) and gold (30) layers onto the structure through a metal mask (27) having holes greater than the said determined size to form an intermediate metal contact pad (33') in the said contact opening and at the close vicinity thereof; b) applying a photoresist layer (31) onto the structure and patterning it to leave a pattern (31) of the said determined size aligned and above said intermediate contact pad (33') exposing the parts thereof in excess; c) delineating the intermediate metal contact pad (33') using said pattern (31) as an in-situ mask and removing the excess metal thereof to provide the final metal contact pad (33) having the said determined size; d) removing the remaining photoresist pattern (31); Adding the steps of: forming a solder ball (34) on the contact pad site. The above method has applicability to the fabrication of contact terminals for high density/high count I/O connections for advanced semiconductor chips that are appropriate for flip-chip (C4) or face-down bonding thereof on metallized ceramic (MC) substrates.