Patent ID: 7224075

Claim:
An apparatus comprising: a substrate; a first die-attach material attaching a first die to the substrate, the first die-attach material having a first associated processing temperature; a second die-attach material attaching a second die to the first die, the second die-attach material having a second associated die-attach material processing; and a third die-attach material attaching a third die to the second die, the third die-attach material having a third associated die-attach material processing temperature, wherein the first associated die-attach material processing temperature is a first laminating temperatures, the second associated die-attach material processing temperature is a second laminating temperature, and the third associated die-attach material processing temperature is a third laminating temperature, wherein the first die-attach material, attaching the first die to the substrate, comprises a first thermoplastic film having a first glass transition temperature, the second die-attach material, attaching the second die to the first die, comprises a second thermoplastic film having a second glass transition temperature that is lower than the first glass transition temperature, and the third die-attach material, attaching the third die to the second die, comprises a third thermoplastic film having a third glass transition temperature that is lower than the second glass transition temperature, and wherein the first die-attach material achieves a different modulus at a different die-attach material processing temperature than that at the second die attach material processing temperature and does not significantly degrade at the second laminating temperature.