Method of copper transport prevention by a sputtered gettering layer on backside of wafer

• Main Authors: HO, PAUL KWOK KEUNG, SUDIJONO, JOHN LEONARD, ALIYU, YAKKUB, CHOOI, SIMON, YI, XU, ZHOU, MEI SHENG, GUPTA, SUBHASH, ROY, SUDIPTO RANENDRA
• Format: Patent
• Language: English; French; German
• Published: 23.01.2002
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; SEMICONDUCTOR DEVICES; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

A method of preventing copper transport on a semiconductor wafer, comprising the following steps. A semiconductor wafer (10) having a front side (11) and a backside (13) is provided. Metal, selected from the group comprising aluminum, aluminum-copper, aluminum-silicon, and aluminum-copper-silicon is sputtered on the backside of the wafer to form a layer of metal (12). The back side sputtered aluminum layer may be partially oxidized at low temperature to further decrease the copper penetration possibility and to also provide greater flexibility in subsequent copper interconnect related processing. Once the back side layer is in place, the wafer can be processed as usual. The sputtered back side aluminum layer can be removed during final backside grinding.