Abstract: A structure for an improved solder terminal is disclosed. The improved solder terminal is made of a bottom metallic adhesion layer, a CrCu intermediate layer on top of the adhesion layer, a solder bonding layer above the CrCu layer and a solder top layer. The adhesion layer is either TiW or TiN. A process for fabricating an improved terminal metal consists of depositing an adhesive metallic layer, a layer of CrCu over the adhesive layer and a layer of solder bonding material, over which a solder layer is formed in selective regions and the underlying layers are etched using solder regions as a mask.

Abstract: A process for an improved solder terminal is disclosed. The improved solder terminal is made of a bottom metallic adhesion layer, a CrCu intermediate layer on top of the adhesion layer, a solder bonding layer above the CrCu layer and a solder top layer. The adhesion layer is either TiW or TiN. A process for fabricating an improved terminal metal consists of depositing an adhesive metallic layer, a layer of CrCu over the adhesive layer and a layer of solder bonding material, over which a solder layer is formed in selective regions and the underlying layers are etched using solder regions as a mask.

Abstract: Etching processes are disclosed for producing a graded or stepped edge profile in a contact pad formed between a chip passivating layer and a solder bump. The stepped edge profile reduces edge stress that tends to cause cracking in the underlying passivating layer. The pad comprises a bottom layer of chromium, a top layer of copper and an intermediate layer of phased chromium-copper. An intermetallic layer of CuSn forms if and when the solder is reflowed, in accordance with certain disclosed variations of the process. In all the variations, the solder is used as an etching mask in combination with several different etching techniques including electroetching, wet etching, anisotropic dry etching and ion beam etching.