UV peelable pressure sensitive adhesives (PSAs), widely used in semiconductor manufacturing, particularly during wafer (silicon wafer) dicing processes, must provide strong adhesion during processing while allowing controlled and easy removal afterward. Addressing this requirement, the new study introduces a UV active peelable adhesive designed by blending a castor oil based urethane acrylate oligomer capable of dual curing, thermal and UV, with a functionally tailored acrylic copolymer.
Strong Adhesion and UV Triggered Release in a Single Formulation
In the study, the adhesive system was formulated as a mixture of an acrylic copolymer, a castor oil based urethane acrylate oligomer, and a reactive diluent. During the thermal curing stage, a reaction occurs between the NCO groups of the oligomer and the hydroxyl groups of the copolymer, resulting in a crosslinked network structure. This reaction significantly increases the initial peel strength and ensures the level of adhesion required during processing.
The Role of Benzophenone and Siloxane
One of the key features of the formulation is the covalent incorporation of benzophenone and siloxane groups into the acrylic backbone. Under UV irradiation, benzophenone groups initiate additional crosslinking, increasing network density, while siloxane groups alter surface properties in a way that facilitates release. As a result, adhesion strength decreases markedly after UV exposure, enabling controlled and clean debonding.
Why It Matters
Such adhesives play a critical role in semiconductor applications where components must be separated quickly, safely, and without damaging sensitive surfaces once wafer dicing is complete. By combining a bio based raw material such as castor oil with functional acrylic chemistry, the study presents an approach that delivers both high initial adhesion and rapid UV triggered debonding. This combination is considered to offer strong potential for improving efficiency and process reliability in precision manufacturing environments.
