Method for forming a temporary attachment between a semiconductor die and a substrate using a metal paste comprising spherical modules

A method for forming a temporary attachment between a semiconductor die and a substrate, comprising the steps of:

• placing a solder paste composed of substantially spherical solder nodules upon a contact pad on the substrate;
• partially melting the solder paste at approximately a lowest melting temperature of the solder paste to get a first partial liquidus region between the spherical solder nodules to partially fuse the spherical solder nodules together;
• aligning an interconnect protrusion on an active surface of the semiconductor die to the contact pad;
• and
• reheating the solder paste at approximately a lowest melting temperature of the solder paste to get a second partial liquidus region to join the interconnect protrusion to the contact pad with a tack joint to form an electrical contact between the semiconductor die and the contact pad.

A method for testing a semiconductor die, comprising the steps of:

• providing a test substrate having a pattern of conductive traces terminating in a plurality of contact pads on a surface of the test substrate;
• placing a metal paste, composed of substantially spherical metallic nodules, upon a contact pad of the plurality of contact pads;
• partially melting the metal paste at approximately a lowest melting temperature of the metal paste to obtain a first partial liquidus region to partially fuse the spherical metallic nodules together;
• aligning an interconnect protrusion on an active surface of the semiconductor die to said contact pad having the metal paste thereon;
• reheating the metal paste at approximately a lowest melting temperature of the metal paste to obtain a second partial liquidus region to join the interconnect protrusion to the contact pad with a tack joint to form an electrical contact between the semiconductor die and the contact pad;
• and
• testing the semiconductor die through contacting the pattern of conductive traces on the test substrate.