On-chip hotplate for temperature control of CMOS SAW resonators

A. N. Nordin, I. Voiculescu, M. Zaghloul
2008 2008 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS  
Substrate Ground Shield Reflector Reflector Input IDT Output IDT SiO Fig.1. Implementation of a two-port SAW resonator structure in CMOS. For clarity, the piezoelectric ZnO layer is not shown [1], SiO2 ZnO Metal 1 Si Substrate Polysilicon Transducer Fig. 2. Cross-section of CMOS SAW Resonator with embedded heaters Abstract-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
more » ... is required. This work presents the design, modeling and characterization of integrated dual-serpentine polysilicon resistors as a method of temperature control for CMOS SAW resonators. The design employs the oven control temperature stabilization scheme where the device's temperature is elevated to higher than T max to maintain constant device temperature. The efficiency of the polysilicon resistor as a heating element was verified through a 1-D partial differential equation model, 3-D CoventorWare ® finite element simulations and measurements using Compix ® thermal camera. To verify that the on-chip hotplate is effective as a temperature control method, 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/ o C has been reduced to -23.19 ppm/ o C when heated to 56 o C. I.
doi:10.1109/dtip.2008.4752955 fatcat:dijhjxea4jb77d4awemkm3rz2i