News Release

As electronic devices become smaller, lighter, and more advanced, they require semiconductor packages that are also smaller, lighter, and able to be mounted more densely on substrates. In response to this need, the focus on packaging technology called Wafer Level Chip Scale Package (WLCSP) has grown in recent years. In contrast to the conventional packaging process, the WLCSP process allows the chip to be directly mounted on the substrate without the need for wire connection and molding. This packaging is no larger than the chip itself, which makes it possible to minimize the size and weight of the device. For this reason, the technology has been adopted in the manufacture of smartphones and computers.

WLCSP is structurally designed with bumps that serve as protruding electrodes to provide an interconnection between the die and substrate. When subjected to thermal deformation, the stress causes these bumps to crack. To solve this issue, Lintec has developed BSF, which boosts the durability and reliability of semiconductor chips using resin to protect the bumps and inhibit cracking of the interconnection.

Lintec BSF is designed so that temperature changes alter the viscosity of the resin, allowing the film to be laminated to the wafer surface while heated so that the film adheres closely to the bumps without air bubbles. BSF can also be used as a back grinding tape to make the wafer thinner and prevents the surface of the circuit from being contaminated by grinding water or grinding dust. When the back grinding tape layer of this film is peeled off after the grinding process, only the BSF layer protecting the bumps remains. No new equipment or changes to the manufacturing process are required, and the film itself can be customized to accommodate bumps of different shapes and sizes.

Lintec will continue to develop tape, equipment, and manufacturing process solutions that enhance the reliability of semiconductor chips.