Due to the sensitivity of the piezoelectric layer
in surface acoustic wave (SAW) resonators to temperature,
a method of achieving device stability as a function of
temperature is required. This work presents two methods of
temperature control for CMOS SAW resonators using
embedded polysilicon heaters. The first approach employs
the oven control temperature stabilization scheme. Using
this approach, the device’s temperature is elevated using
on-chip heaters to Tmax = 42°C to maintain constant
device temperature. Both DC and RF measurements of the
heater together with the resonator were conducted.
Experimental results have indicated that the TCF of the
CMOS SAW resonator of -97.2 ppm/°C has been reduced
to -23.19 ppm/°C when heated to 42°C. The second
scheme uses a feedback control circuit to switch the onchip
heaters on and off depending on the ambient temperature.
This method provided reduction of the TCF from
-165.38 ppm/°C, to -93.33 ppm/°C. Comparison of both
methods was also provided
