SURFACE TREATMENTS FOR CONTACT PADS USED IN SEMICONDUCTOR CHIP PACKAGES AND METHODS OF PROVIDING SUCH SURFACE TREATMENTS

摘要

An inorganic solder mask (48) for use as a surface treatment in masking a connection conductor (32) of a semiconductor chip package (10) against solder wetting when mounting the chip package (10) to a printed wiring board (50) or other substrate. The connection conductor (32) is partially covered by a metallization contact (42) formed from a distinct metal. The inorganic solder mask (46) is applied to an exposed portion (44) of the connection conductor (32) not covered by the metallization contact (42). The metallization contact (42) is not coated by the inorganic solder mask (46). The presence of the inorganic solder mask (46) significantly reduces or prevents wetting of the exposed portion (44) when molten solder is present on the connection conductor (32) without affecting the solidified solder layer (48) formed on the metallization contact (42). As a result, an extraneous mass of solder does not solidify on the exposed portion (44) of the connection conductor (32).