The semiconductor industry continues to move toward higher computing power and higher power consumption, driving continuous upgrades in chip packaging processes. From traditional epoxy underfill to the growing demand today for materials with high thermal conductivity and low stress, the application boundaries of liquid silicone rubber (LSR) in semiconductor packaging are gradually being expanded.

The core material requirements for chip packaging are: high thermal conductivity, a low coefficient of thermal expansion (CTE), and low curing stress. The thermal conductivity of LSR can be formulated to reach high levels, while its flexibility helps create a stress buffer layer between the chip and the substrate, reducing the risk of solder joint cracking caused by CTE mismatch.

Currently, the application of LSR in the semiconductor field is concentrated in several areas: first, as underfill material, replacing some traditional epoxy materials to reduce packaging stress; second, as potting protection for power devices, combining thermal conductivity with electrical insulation; and third, as a temporary bonding and protective coating in wafer-level packaging.

Looking at industry trends, with the widespread adoption of Chiplet technology and 3D packaging, thermal management and stress control inside chips are becoming more complex. LSR, thanks to its tunable hardness, thermal conductivity, and elastic modulus, is expected to find more application opportunities in these new processes.

Furthermore, against the backdrop of extremely high cleanliness requirements in advanced packaging, the low volatile organic compound (VOC) characteristics of LSR are an added advantage. When selecting materials, key parameters to focus on include: thermal conductivity, CTE matching, curing shrinkage, and compatibility with semiconductor processes.

It is foreseeable that as semiconductor packaging processes continue to evolve, the penetration of LSR into this field is likely to deepen further.

More information, please click here.