The high performance GaN light emitting diode (LED) from sapphire wafer has been transferred on a plastic substrate
with 308nm XeCl laser lift-off (LLO) for next generation flexible lighting applications. SU-8 passivation with
thermal release tape (TRT) adhesive enables structure coverage and adhesion so that it can be an excellent candidate for
a carrier substrate for non-wetting transfer process using laser liftoff technology. The dimensions of the laser beam are
also investigated in two types (3μm x 5cm and 1.2mm x 1.2mm) to reduce stress when decomposition of GaN occurs.
With careful optimization of carrier substrate and laser beam conditions, we can fabricate flexible GaN LED on
polyimide substrates which shows similar electrical properties to the GaN LED on bulk sapphire substrate.
We propose an advanced time synchronization scheme with additional pre-processor for OFDM systems. The proposed pre-processor scheme makes symbol synchronization and guard-interval length detection possible, even though there is no guard-interval length information. This pre-processor is so useful in the systems like DVB-T, which have several kinds of guard-interval lengths. Simulation results show that the proposed scheme gives satisfactory performance in the guard-interval length detection and the OFDM symbol synchronization over AWGN.