Semiconductor package with flip chip solder joint capsules

A method of forming a semiconductor package comprising:

• applying a viscous polymeric precursor to either each of a set of die contacts of a semiconductor die, or to electrical contact areas of a die attach site of a leadframe;
• positioning the semiconductor die on the die attach site in a flip chip configuration with the viscous polymeric precursor covering solder of each of the set of die contacts;
• reflowing the solder of each of the set of die contacts to form a set of solder joints to electrically connect each die contact of the set of die contacts to the electrical contact areas of leadframe in the flip chip configuration;
• curing the viscous polymeric precursor to form a set of solder joint capsules covering each of the set of solder joints against the leadframe;
• positioning a clip on the leadframe over the semiconductor die;
• and
• reflowing solder between the clip and the leadframe to form a clip solder joint.

A semiconductor package comprising:

• a leadframe forming a plurality of die leads with a die attach site, sensor coil leads and a first sensor coil between the sensor coil leads;
• a semiconductor die including a set of metal pillars mounted to the die attach site in a flip chip configuration with each metal pillars of the set of metal pillars electrically connected to leadframe via one of a set of solder joints;
• a set of solder joint capsules covering each of the set of solder joints against the leadframe,
• wherein each of the set of metal pillars extends from an opening of a dielectric layer on an active side of the semiconductor die, through one of the set of solder joint capsules, and to one of the set of solder joints;
• a clip mounted to the leadframe over the semiconductor die with a clip solder joint,
• wherein the clip includes a second sensor coil, the second sensor coil forming a parallel conductive path with the first sensor coil via the clip solder joint,
• wherein the semiconductor die includes a sensor operable to detect magnetic fields created by electrical current through the first sensor coil and the second sensor coil, the semiconductor die operable to output a signal representative of the detected magnetic fields via the die leads;
• and
• a dielectric mold compound covering the set of solder joints of the flip chip configuration and the set of solder joint capsules and at least partially covering the leadframe, the semiconductor die, and the clip,
• wherein the dielectric mold compound contacts each of the set of metal pillars adjacent to the dielectric layer on the active side of the semiconductor die.