Micro-processing in the ultraviolet: UV laser applications in manufacturing consumer electronics (Conference Presentation)

The world market for laser micro-processing has seen a tremendous increase within the last 24 months triggered predominantly by large scale projects in the electronics industry. By far the largest contribution to this growth came from UV nano- and picosecond lasers for various applications for manufacturing consumer electronics devices. The process chain of flexible OLED display used in smart devices (phones, watches, tablets) is heavily relying on ultraviolet lasers: Debonding of the large display foils (typically 1500 x 1850 mm²) from the carrier glass they are produced on is a critical process since it is one of the last steps in the process chain at the peak of the added value. UV nanosecond lasers enable reliable debonding (laser lift-off) without risking any damage to the displays. Subsequently, the display cells are singulated by laser cutting. Also this process step relies heavily on UV lasers, but in this case with ultrashort pulses. The combination of ultrashort pulse duration and short wavelength allows efficient and precise cutting of these multi-layer materials without unwanted heat affected zones or even thermal damage to the electronics in the display. Various additional parts that are integrated in smart devices like polarizer foils and flexible printed circuit boards are based on multi-material foils and are cut to their net shape with UV nanosecond or ultrashort pulsed lasers. In this contribution we present an overview of the different UV laser processes and compare the process results from ns, ps and fs lasers to give an outlook on future applications.