2.4 GHz SAW filters using AlN deposited on off-angle R-plane sapphire substrates by MOCVD

A-plane AlN films deposited on off-angle R-plane sapphire substrates, in which a surface plane was tilted towards [1-101] sapphire direction, were shown to be effective in restraining the generation of inverted twins. Surface acoustic wave (SAW) filters at 2.4 GHz were reliably made using the optimized AlN on the off-angle sapphire substrate. 2.4 GHz spread spectrum (SS) signals were able to be directly demodulated to baseband data using the optimized front-end SAW matched filter (MF) and delay line (DL) on the AlN.