RESUMO
Carbon nanotube-FETs (CNTFETs) have become a potential challenger because of their exceptional electrical properties and compatibility with conventional CMOS technology. The design and study of digitally tunable transconductance amplifiers (DTTAs) using CNTFETs are the main topics of this work. By utilizing the special characteristics of CNTFETs, the suggested DTTA design makes transconductance tunable, providing a versatile method of adjusting amplifier settings without requiring modifications to the hardware architecture. This study provides a complete description of the CNTFET modeling techniques utilized for realistic circuit simulations, along with a detailed analysis of the DTTA based on CNTFETs. The circuit is implemented using a 32 nm CNTFET model and verified results with HSPICE.
RESUMO
In this paper, the study is supported by design, FEA simulation, and practical RF measurements on fabricated single-port-cavity-based acoustic resonator for gas sensing applications. In the FEA simulation, frequency domain analysis was performed to enhance the performance of the acoustic resonator. The structural and surface morphologies of the deposited ZnO as a piezoelectric layer have been studied using XRD and AFM. The XRD pattern of deposited bulk ZnO film indicates the perfect single crystalline nature of the film with dominant phase (002) at 2θ = 34.58°. The AFM micrograph indicates that deposited piezoelectric film has a very smooth surface and small grain size. In the fabrication process, use of bulk micro machined oxide (SiO2) for the production of a thin membrane as a support layer is adopted. A vector network analyzer (Model MS2028C, Anritsu) was used to measure the radio frequency response of the resonators from 1 GHz to 2.5 GHz. As a result, we have successfully fabricated an acoustic resonator operating at 1.84 GHz with a quality factor Q of 214 and an effective electromechanical coupling coefficient of 10.57%.