The vast majority of RFIC devices used in cellular phones and wireless infrastructures are made of GaAs substrates. GaAs material is most competitive for high frequency, high speed and/or low power consumption for components such as power amplifiers and switches. ASMPT is Market leader in processing RFIC wafers.
Bulk Acoustic Wave (BAW) Filters are RF bandpass filters that can be used in a wide range of applications up to 6 GHz. BAW filters have a quartz crystal substrate with metal patches on the top and bottom side of the quartz. These metal patches excite the acoustic waves, which propagates vertically between them to form a standing acoustic wave. The resonant frequency is determined by the thickness of the slab and the mass of the electrodes. We see FBAR and SMR filters
A Surface Acoustic Wave (SAW) filter working principle is based on transferring the electrical signal into an acoustic wave over piezo-electrical material like quartz. On top of this material, bars transfer the electrical signal into mechanical waves and backwards. SAW bandpass filters are used in the frequency range of 50 MHz to 3 Ghz
Tuners & Switches
Tuners & Switches in modern mobile phones has become increasingly complex due to the growing number of frequency bands. More antennas (up to 8) are required to deliver higher data rates. At the same time, the space available for the mobile system antenna has shrunk, lowering the antenna’s efficiency. Some of this lost performance can be recovered with antenna tuning. They allow antennas to be efficient across the entire LTE and 5G bands, while saving battery power and thin phone designs