UV adhesive for chip encapsulation, IC component fixing, sealing, bonding, filling, protection, UV photothermal curing.

Core Application Scenarios of UV Adhesives for Chip Packaging

In chip packaging, UV adhesives are mainly classified into the following categories based on their function and application location:

Die Bonding:

Scenario: Bonding bare chips to a substrate (such as leadframes, PCBs).

Requirements: These adhesives typically need to be thermally conductive but insulating (unless they are conductive) and able to withstand the high temperatures of subsequent wire bonding and reflow soldering processes. UV curing may be used as pre-fixation here, followed by a thermal curing process.

Chip Encapsulation:

Scenario: Encapsulating and protecting individual, miniaturized chips (such as chips on CSPs, BGAs) or sensors.

Requirements: Requires excellent resistance to moisture, chemical corrosion, mechanical shock, and alpha particle radiation. Low stress and high purity are typically required.

Underfill:

Scenario: This is one of the most classic and important applications, mainly used for flip chip packaging such as BGAs and CSPs. Adhesive is used to fill the gap between the chip and the substrate.

Objective: To compensate for the difference in thermal expansion coefficients between the chip, solder balls, and substrate through the strong adhesive force of the colloid, uniformly distributing stress and greatly improving the reliability of solder joints against thermal fatigue, preventing solder joint cracking.

Requirements: Good flowability (capillary action) to quickly fill narrow gaps, low thermal expansion coefficient, and high reliability.

Wafer-level packaging:

Scenario: Operations are performed on the entire wafer, such as temporary bonding (adhering the wafer to a carrier for thinning) or as a dielectric material for redistribution layers.

Requirements: Extremely high flatness, purity, and ease of debonding.