Flexible OLED displays are manufactured using the Laser-Lift-Off process. A UV DPSS-Laser and INNOVAVENT Line Beam Optics are integrated into production systems. Low cost of ownership and unbeaten reliability is provided for the Laser-Lift-Off (LLO), respectively UV-Laser-Peeling (ULP) process.
The OLED display is manufactured on a polymer foil. This polymer foil is sealed to a glass substrate during the manufacturing process. After completion of the OLED display the polymer foil is removed from the glass by the Laser-Lift-Off process. The Laser-Lift-Off is using 343nm or 355nm UV laser light formed to a line geometry. This wavelength transmits through the glass substrate (typical 0,5mm thick) without attenuation and is absorbed in a thin “sacrifice layer” (50-60nm a-Si) or at the glass polymer interface. The absorbed pulsed energy results in a lift off of the polymer substrate from the glass without any damage to the display. The full display is scanned through the laser line and fully lifted off.
The glass substrates size starts from mobile display dimensions (100mm line length) up to Gen 6 (1500mm x 1850mm).
VOLCANO UV Laser Optics generate a laser line of 100mm to 750mm length and a width of 20-30µm FWHM. The line is focused on the polyimide through the glass at an energy density of 150-500mJ/cm² and scanned with a typical pitch of 10-20µm (scan speed 100-200mm/s). The TruMicro 8320/8340 laser emits 15-20ns pulses at 10 kHz. When applying a sacrifice layer (50-60nm a-Si) between the glass and the polyimide higher energy density of up to 500mJ/cm2 is required.