Used as a photoacid generator (PAG) in advanced photolithography processes, particularly in semiconductor manufacturing. Upon exposure to deep ultraviolet (DUV) or extreme ultraviolet (EUV) light, it releases a strong acid that catalyzes chemical transformations in photoresist materials, enabling precise pattern development on silicon wafers. Its sulfonium cation provides high thermal stability and efficient acid generation, while the methylthiophenyl and phenyl groups help tune solubility and reactivity. Commonly employed in chemically amplified resists for high-resolution patterning in microelectronics fabrication.