ALSCN-ON-DIAMOND SAW RESONATORS
May18, 2025
A novel surface acoustic wave (SAW) resonator platform using Aluminum Scandium Nitride (AlScN) on polycrystalline diamond, optimized for Ku-band frequencies (12–18 GHz).
The platform leverages the Sezawa acoustic mode to overcome limitations of traditional Rayleigh-mode SAW devices in terms of phase velocity, power handling, and frequency scalability.
Material Stack:
200 nm Al₀.₇Sc₀.₃N thin film
300 µm polycrystalline CVD diamond substrate
50 nm Aluminum electrodes
Key Performance Metrics at 12.9 GHz (Sezawa mode):
Phase Velocity (Vp): 8671 m/s
Electromechanical Coupling (keff²): 2.1%
Bode-Q (Qmax): 408
Power Handling: >12.5 dBm without performance degradation
Comparative Advantages
| Feature | AlScN-on-Diamond | SiC | Sapphire | LN-on-Si |
|---|---|---|---|---|
| Vp (m/s) | 8671 | 6490 | 6045 | 3210 |
| keff² (%) | 2.1 | ~1.8 | <1.5 | ~1 |
| Power Handling (dBm) | >12.5 | Moderate | Poor | Poor |
| Qmax | 408 | 380 | <300 | <100 |
