Diamond-like carbon (DLC) coated tips have been successfully applied in field emitter arrays, and scanning probe microscope (SPM) based nanofabrications. DLC deposition on tips is conventionally realized by thermal and plasma-enhanced chemical vapor deposition processes. In this study, we use laser-assisted method employing strongly enhanced near field around the tip apex for DLC deposition. DLC films were deposited on tungsten (W) tips under KrF excimer laser irradiation in a benzene solution and in a laser chemical vapor deposition (LCVD) chamber. Simulation results showed a highly localized optical field enhancement at the tip apex. There was also an optical-field gradient from apex to tip body. Experiment results showed that a locally confined DLC film was deposited based on energy dispersive X-ray (EDX) analysis. Raman spectra showed that at positions close to apexes, films tend to be more diamond-like. This implies that quality of DLC film varies according to local optical intensity along the tip. Hence, the deposition process was confirmed to be induced by the local near field generated by laser and nanotip interaction.
Laser processing has large potential in the packaging of integrated circuits (IC). It can be used in many applications such as laser cleaning of IC mold tools, laser deflash to remove mold flash from heat sinks and lead wires of IC packages, laser singulation of BGA (ball grid array) and CSP (chip scale packages), laser reflow of solder ball on GBA, laser peeling for CSP, laser marking on packages and on Si wafers. Laser nanoimprinting of self-assembled nanoparticles has been recently developed to fabricate hemispherical cavity arrays on semiconductor surfaces. This process has the potential applications in fabrication and packaging of photonic devices such as waveguides and optical interconnections. During the implementation of all these applications, laser parameters, material issues, throughput, yield, reliability and monitoring techniques have to be taken into account. Monitoring of laser-induced plasma and laser induced acoustic wave has been used to understand and to control the processes involved in these applications. Numerical simulations can provide useful information on process analysis and optimization.