This project investigates new materials suitable for achieving Q-factors in excess of 1 million in resonating gyroscopes. Experimental studies of dissipation caused by thermoelastic and surface losses will be performed using resonator test structures. The effect of doping and microstructure is explored on CVD diamond MEMS resonators. Hundreds of surface micromachined double ended tuning fork (DETF) resonators were fabricated in nanocrystalline diamond (NCD) and microcrystalline diamond (MCD) films deposited using hot filament CVD technique with varying levels of Boron doping. Higher boron doping resulted in reduced Q due to defect losses. Moreover, the thermal conductivity of diamond films were measured using TDTR technique for further mapping of theory and experiment.
- Hadi Najar
- Chen Yang (UC Berkeley)
- Najar, H.; Thron, A; Yang, C.; Fung, S.; van Benthem, K.; Lin, L.; Horsley, D.A, “Increased thermal conductivity polycrystalline diamond for low-dissipation micromechanical resonators,” Micro Electro Mechanical Systems (MEMS), 2014 IEEE 27th International Conference on , vol., no., pp.628,631, 26-30 Jan. 2014
- A. Heidari, M.-L. Chan, H.-A. Yang, G. Jaramillo, P. Taheri-Tehrani, P. Fonda, H. Najar, K. Yamazaki, L. Lin, and D. A. Horsley, “Hemispherical wineglass resonators fabricated from the microcrystalline diamond,” J. Micromech. Microeng., vol. 23, no. 12, p. 125016, Dec. 2013.
- Heidari, A; Chan, M.-L.; Yang, H.-A; Jaramillo, G.; Taheri-Tehrani, P.; Fonda, P.; Najar, H.; Yamazaki, K.; Lin, L.; Horsley, D.A, “Micromachined polycrystalline diamond hemispherical shell resonators,” Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS & EUROSENSORS XXVII), 2013 Transducers & Eurosensors XXVII: The 17th International Conference on , vol., no., pp.2415,2418, 16-20 June 2013
- H. Najar, A. Heidari, M.-L. Chan, H.-A. Yang, L. Lin, D. G. Cahill, and D. A. Horsley, “Microcrystalline diamond micromechanical resonators with quality factor limited by thermoelastic damping,” Applied Physics Letters, vol. 102, no. 7, p. 071901, Feb. 2013.
- Najar, H.; Mei-Lin Chan; Jin Xie; Liwei Lin; Horsley, D.A, “Impact of doping and microstructure on quality factor of CVD diamond micromechanical resonators,” Frequency Control Symposium (FCS), 2012 IEEE International , vol., no., pp.1,5, 21-24 May 2012