Method of making a semiconductor chip assembly with an aluminum post/base heat spreader and a silver/copper conductive trace

A method of making a semiconductor chip assembly, comprising:

• providing a post, a base, an adhesive and a copper layer, wherein
• the post is adjacent to the base, extends above the base in an upward direction, extends into an opening in the adhesive, is aligned with an aperture in the copper layer and is aluminum,
• the base extends below the post in a downward direction opposite the upward direction, extends laterally from the post in lateral directions orthogonal to the upward and downward directions and is aluminum,
• the adhesive is mounted on and extends above the base, is sandwiched between the base and the copper layer and is non-solidified, and
• the copper layer is mounted on and extends above the adhesive;
• then
• flowing the adhesive into and upward in a gap located in the aperture between the post and the copper layer;
• solidifying the adhesive;
• then
• providing a conductive trace that includes a pad and a terminal, wherein the conductive trace further includes a silver coating and a copper core, the silver coating is located above and overlaps the copper core, and the copper core is a selected portion of the copper layer that is coplanar with the post and the adhesive at a lateral surface that includes the post, the adhesive and the copper core and faces in the upward direction;
• then
• mounting a semiconductor device on the post, wherein an aluminum heat spreader includes the post and the base and the semiconductor device is mounted on and overlaps the post;
• electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal;
• and
• thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

A method of making a semiconductor chip assembly, comprising:

• providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions and the post and the base are aluminum;
• providing an adhesive, wherein an opening extends through the adhesive;
• providing a copper layer, wherein an aperture extends through the copper layer;
• mounting the adhesive on the base, including inserting the post into the opening, wherein the adhesive extends above the base and the post extends into the opening;
• mounting the copper layer on the adhesive, including aligning the post with the aperture, wherein the copper layer extends above the adhesive and the adhesive is sandwiched between the base and the copper layer and is non-solidified;
• then
• applying heat to melt the adhesive;
• moving the base and the copper layer towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the copper layer, wherein the pressure forces the molten adhesive to flow into and upward in a gap located in the aperture between the post and the copper layer;
• applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the copper layer;
• then
• providing a conductive trace that includes a pad and a terminal, wherein the conductive trace further includes a silver coating and a copper core, the silver coating is located above and overlaps the copper core, the copper core is a selected portion of the copper layer that is coplanar with the post and the adhesive at a lateral surface that faces in the upward direction, the silver coating and the copper core provide portions of the pad and the pad is electrically connected to the terminal;
• then
• mounting a semiconductor device on the post, wherein an aluminum heat spreader includes the post and the base and the semiconductor device overlaps the post;
• electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal;
• and
• thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

A method of making a semiconductor chip assembly, comprising:

• providing a post, a base, an adhesive and a substrate, wherein
• the substrate includes a copper layer and a dielectric layer,
• the post is adjacent to the base, extends above the base in an upward direction, extends through an opening in the adhesive, extends into an aperture in the substrate and is aluminum,
• the base extends below the post in a downward direction opposite the upward direction, extends laterally from the post in lateral directions orthogonal to the upward and downward directions and is aluminum,
• the adhesive is mounted on and extends above the base, is sandwiched between the base and the substrate and is non-solidified,
• the substrate is mounted on and extends above the adhesive, and the copper layer extends above the dielectric layer, and
• a gap is located in the aperture between the post and the substrate;
• then
• flowing the adhesive into and upward in the gap;
• solidifying the adhesive;
• then
• mounting a semiconductor device on the post, wherein an aluminum heat spreader includes the post and the base, the semiconductor device overlaps the post, a conductive trace includes a pad and a terminal and further includes a silver coating and a copper core, the silver coating is located above and overlaps the copper core, the copper core is a selected portion of the copper layer that is coplanar with the post and the adhesive at a lateral surface that faces in the upward direction, the silver coating and the copper core provide portions of the pad and the pad is electrically connected to the terminal;
• electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal;
• and
• thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.

A method of making a semiconductor chip assembly, comprising:

• providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions and the post and the base are aluminum;
• providing an adhesive, wherein an opening extends through the adhesive;
• providing a substrate that includes a copper layer and a dielectric layer, wherein an aperture extends through the substrate;
• mounting the adhesive on the base, including inserting the post through the opening, wherein the adhesive extends above the base and the post extends through the opening;
• mounting the substrate on the adhesive, including inserting the post into the aperture, wherein the substrate extends above the adhesive, the copper layer extends above the dielectric layer, the post extends through the opening into the aperture, the adhesive is sandwiched between the base and the substrate and is non-solidified, and a gap is located in the aperture between the post and the substrate;
• then
• applying heat to melt the adhesive;
• moving the base and the substrate towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the substrate, wherein the pressure forces the molten adhesive to flow into and upward in the gap and the post and the molten adhesive extend above the dielectric layer;
• applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the substrate;
• then
• mounting a semiconductor device on the post, wherein an aluminum heat spreader includes the post and the base, the semiconductor device overlaps the post, a conductive trace includes a pad and a terminal and further includes a silver coating and a copper core, the silver coating is located above and overlaps the copper core, the copper core is a selected portion of the copper layer that is coplanar with the post and the adhesive at a lateral surface that faces in the upward direction, the silver coating and the copper core provide portions of the pad and the pad is electrically connected to the terminal;
• electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal;
• and
• thermally connecting the semiconductor device to the post, thereby thermally connecting the semiconductor device to the base.