Table 1 Thickness and composition of deposited layers
From: Porous silicon bulk acoustic wave resonator with integrated transducer
Nominal | Impedance | Longitudinal | ||
|---|---|---|---|---|
Function | Material | thickness (nm) | (MRayl) | velocity (ms− 1) |
Top electrode | AlCu | 130 | 17 | 6,420 |
W | 120 | 101 | 5,230 | |
Piezo layer | AlN | 1300 | 37 | 10,400 |
Bottom electrode | W | 170 | 101 | 5,230 |
AlCu | 200 | 17 | 6,420 | |
Coupling layer | SiO2 | 500 | 13 | 5,970 |
Seal to PSi | Amorphous Si | 20 | 20 | 8,400 |
Porous layer/multilayers | PSi | variable | variable | variable |