Sintering is one of the emerging technologies in power devices because of its compatibility to high operating temperature packages that the Silicon Carbide (SiC) and Gallium Nitride (GaN) packages normally require. Moreover, packages that have been processed through sintering have advantages that include high thermal conductivity, high electrical conductivity, low process temperatures and high reliability and compliance compared with the existing semiconductor devices.
TEAM Pacific Corporation, through its new process qualification group, has successfully built prototype samples of a semiconductor device that has undergone silver sintering process at die attach. The silver sintering paste used in the said evaluation is low temperature, pressure-less silver-based paste with Nano-silver technology. The process involves printing the silver paste to the substrate, followed by the placing of the die/chip on the unit and then loading it in an oven. Temperature setting and profile optimization was done to ensure that the silver paste will be cured thus completing the binding of silver Nano-particles (sintering phase).
Measure of quality involves visual inspection, solder voids inspection through X-ray, and bondline thickness. One property of silver paste is that the appearance of the solder coverage prior oven curing will most likely be the same after. Units subjected to silver sintering were observed to have better solder coverage visually and this was confirmed through X-ray inspection as seen on Figure 1.
Figure 1: X-ray Image of Die to Substrate Interface using Sintering
As part of the result, minimum solder void requirement was achieved. More so, consistency of the sintering material is also much better compared to conventional pastes. Bondline thickness of less than 1.2 mils can be achieved which translates to improved thermal and electrical characteristics. Continuous development is being done and Team Pacific Corporation is very much happy on these results.
Want to know more about silver sintering process and products? Team Pacific Corporation is very much willing to qualify silver sintering products with you. Kindly send us an email to tpc-customer@teamglac.com and we’ll be more than happy to provide you with more information.