Laser lift-off for OLED displays

© Foto | Maurizio Pesce (CC BY 2.0, detail)

Laser beams detach sensitive OLED film displays from the carrier glass. Here solid state lasers work extra efficiently and with low maintainance.

Curved but rigid displays – and bendable panels in the future – are on the advance, particularly for the so-called “wearables” – smart devices that one wears on the body – glasses or a wristband, for example.

To make up such displays the electronics industry coats backing glass panes with polyimide. The dried plastic then forms the substrate for the flexible display. Organic light-emitting diodes (OLEDs) are then applied to the polyimide. Once this has been done, the flexible display is to be released from the backing pane.

To do this, a laser beam is aimed from the rear, through the backing glass, and onto the surface of the polyimide film. It heats up the film which when then loses adhesion and detaches from the backing pane. The sensitive OLEDs are completely untouched by the process.

It's that easy: A laser beam is aimed through the backing glass, and onto the surface of the polyimide film. It heats up the film which then loses adhesion.  Illustration | TRUMPF

It’s that easy: A laser beam is aimed through the backing glass, and onto the surface of the polyimide film. It heats up the film which then loses adhesion. Illustration | TRUMPF

 

Highly efficient solid state laser

TruMicro Series 7000

The short pulsed lasers of the TruMicro Series 7000 offer high productivity in microprocessing, with an average power of up to 750 watts. Depending on wavelength, pulse durations of 30 ns or 300 ns can be used.

TRUMPF has developed a process using the solid-state laser TruMicro 7370. When compared with the excimer laser normally employed here, the beam source requires little maintenance, increases the available operating time, and thus lowers production costs. The very short pulses make the process highly efficient, since a single pulse can work a larger surface area.

The TruMicro 7370 is extremely precise in its work and highly reliable in the process. This is due to the great stability of the pulse energy and the temporal sequence of the pulses. Both are ensured by TRUMPF with a special pulse synchronization technology. The regulation installed here lends additional stability to the overall process.

Contact

Christof Siebert
Head of Industry Management Microelectronics
e-mail: Christof.Siebert@de.trumpf.com
phone: +49 7156 303-30116

Required fields: Comment, Name & Mail (Mail will not be published).