A packaged semiconductor device with a particle roughened surface on a portion of the lead frame that improves adhesion between the molding compound and the lead frame. A packaged semiconductor device with a particle roughened surface on a portion of the lead frame that improves adhesion between the molding compound and the lead frame and with a reflow wall that surrounds a portion of the solder joint that couples the semiconductor device to the lead frame. A packaged semiconductor device with a reflow wall that surrounds a portion of a solder joint that couples a semiconductor device to a lead frame.

When a semiconductor element is bonded to a base plate electrode, a cushioning is used for protecting the surface of the semiconductor element. A protrusion having an outwardly cutting shape is formed around an area on the base plate electrode for bonding the semiconductor element to disperse and reduce shear force acting on the cushioning during the bonding, so that no cushioning adheres to the surface of the semiconductor element after bonding.

A solder bump structure includes a pillar formed on an electrode pad. The pillar has a concave curve-shaped surface and a geometry defined at least in part by dimensions including a first height greater than a first width. The solder bump structure further includes solder formed on the concave curve-shaped surface of the pillar. The solder has a convex top surface and having dimensions including a second height greater than a second width due to the geometry of the pillar.

A microelectronic device has bump bond structures on input/output (I/O) pads. The bump bond structures include copper-containing pillars, a barrier layer including cobalt and zinc on the copper-containing pillars, and tin-containing solder on the barrier layer. The barrier layer includes 0.1 weight percent to 50 weight percent cobalt and an amount of zinc equivalent to a layer of pure zinc 0.05 microns to 0.5 microns thick. A lead frame has a copper-containing member with a similar barrier layer in an area for a solder joint. Methods of forming the microelectronic device are disclosed.

A microelectronic device has bump bond structures on input/output (I/O) pads. The bump bond structures include copper-containing pillars, a barrier layer including cobalt and zinc on the copper-containing pillars, and tin-containing solder on the barrier layer. The barrier layer includes 0.1 weight percent to 50 weight percent cobalt and an amount of zinc equivalent to a layer of pure zinc 0.05 microns to 0.5 microns thick. A lead frame has a copper-containing member with a similar barrier layer in an area for a solder joint. Methods of forming the microelectronic device are disclosed.

A method of the present invention includes preparing a substrate having a surface on which a electrode pad is formed, forming a resist layer on the substrate, the resist layer having an opening on the electrode pad, filling conductive paste in the opening of the resist layer; sintering the conductive paste in the opening to form a conductive layer which covers a side wall of the resist layer and a surface of the electrode pad in the opening, a space on the conductive layer leading to the upper end of the opening being formed, filling solder in the space on the conductive layer and removing the resist layer.

A microelectronic device has a pillar connected to an external terminal by an intermetallic joint. Either the pillar or the external terminal, or both, include copper in direct contact with the intermetallic joint. The intermetallic joint includes at least 90 weight percent of at least one copper-tin intermetallic compound. The intermetallic joint is free of voids having a combined volume greater than 10 percent of a volume of the intermetallic joint; and free of a void having a volume greater than 5 percent of the volume of the intermetallic joint. The microelectronic device may be formed using solder which includes at least 93 weight percent tin, 0.5 weight percent to 5.0 weight percent silver, and 0.4 weight percent to 1.0 weight percent copper, to form a solder joint between the pillar and the external terminal, followed by thermal aging to convert the solder joint to the intermetallic joint.

A packaged semiconductor device with a particle roughened surface on a portion of the lead frame that improves adhesion between the molding compound and the lead frame. A packaged semiconductor device with a particle roughened surface on a portion of the lead frame that improves adhesion between the molding compound and the lead frame and with a reflow wall that surrounds a portion of the solder joint that couples the semiconductor device to the lead frame. A packaged semiconductor device with a reflow wall that surrounds a portion of a solder joint that couples a semiconductor device to a lead frame.

A microelectronic device has bump bond structures on input/output (I/O) pads. The bump bond structures include copper-containing pillars, a barrier layer including cobalt and zinc on the copper-containing pillars, and tin-containing solder on the barrier layer. The barrier layer includes 0.1 weight percent to 50 weight percent cobalt and an amount of zinc equivalent to a layer of pure zinc 0.05 microns to 0.5 microns thick. A lead frame has a copper-containing member with a similar barrier layer in an area for a solder joint. Methods of forming the microelectronic device are disclosed.

A microelectronic device has bump bond structures on input/output (I/O) pads. The bump bond structures include copper-containing pillars, a barrier layer including cobalt and zinc on the copper-containing pillars, and tin-containing solder on the barrier layer. The barrier layer includes 0.1 weight percent to 50 weight percent cobalt and an amount of zinc equivalent to a layer of pure zinc 0.05 microns to 0.5 microns thick. A lead frame has a copper-containing member with a similar barrier layer in an area for a solder joint. Methods of forming the microelectronic device are disclosed.