CLUSTERLINE 200 II Bulk-Acoustic-Wave and Surface-Acoustic-Wave Applications
Addressing the requirements of the resonator market
BAW (FBAR/SMR) filters are key components in the RF front-ends of wireless mobile communication devices. They rely on the deposition of thin piezo-electric films, as well as metal electrodes, where film properties and uniformity are key to the device operation. Oerlikon has developed a dedicated resonator manufacturing solution based on its CLUSTERLINE 200 II platform, which includes the deposition of high quality piezo-electric materials like Aluminum-nitride (AlN) and the associtaed electrodes (Mo, Pt, Al, W, Ti, ...) and dielectric (SiO2) films.
CLUSTERLINE 200 II - Benefits
- Single wafer, reactive pulsed-DC magnetron sputtering technology for 100, 150 and 200mm wafer sizes
- Sputter source for high uniformity piezo and electrode films, enabling dynamic adjustment of film uniformity over target life
- Excellent control of process pressure, gas flow and temperature uniformities for best piezoelectric film properties
- Integrated soft/clean-etch process module for surface treatment and layer smoothing
- RF bias for piezo layer stress control
- Excellent process stability at high deposition rates for maximized throughput and yield control
AlN film properties
Typical AlN orientation obtained on various sublayers
| Sublayer | Si or Si02 | Mo | P |
|---|---|---|---|
| AIN c-axis orientation FWHM | < 1.0° | < 1.5° | < 1.5° |
Typical AlN thickness properties (150mm wafer)
| Within-wafer uniformity | < 1.0% 3σ |
|---|---|
| Wafer-to-wafer repeatability | < 1.5% 3σ |
| Deposition rate | Up to 100nm/min-1 |
Legend: SEM cross-section image showing the SMR-type film stack
PECVD Plasma Box for SAW passivation - Benefits
- Excellent temperature uniformity and control thanks to Plasma Box concept - No temperature gradient between front and backside of wafer
- High repeatability of material properties due to self-cleaning capability
- Large process window
- Large expertise in nitride deposition, SiN PECVD layer properties meeting SAW passivation requirements