摘要 |
A semiconductor device (10) is provided with copper traces 916) for connecting active elements to an external device, and insulating layers of black oxide (90) (cupric oxide) are formed on the traces. The active elements may be, for example, conductors on the active surface of a semiconductor die (12). The external device may be, for example, a memory device or an input/output device. The invention eliminates the need for a resist solder mask. The black oxide (90) prevents solder from adhering to the traces except where desired. The black oxide layers preferably do not cover the entire surfaces of the semiconductor device (10). The oxide layers grow only on the surfaces of the copper traces. Consequently, the dimensions of the finished device may be minimized. Black oxide may also be used to promote adhesion between the die and the substrate. |