Design of Au/Cdbr2/Au as Negative Capacitance Devices and as Band Filters Suitable for 4G Technologies

• Autor(a) principal: Qasrawi,A. F.
• Data de Publicação: 2021
• Outros Autores: Hamarsheh,Areen A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Materials research (São Carlos. Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000600224
• topic: CdBr2; 4G band filter; negative capacitance; microwave resonators

Herein, cadmium bromide thin film devices are designed for possible use in communication technology. The 1.0 μ m thin layer of CdBr2 is sandwiched between two Au (1.0 μ m thick) layers using the thermal evaporation technique under a vacuum pressure of 10-5 mbar. The Au/CdBr2/Au devices are structurally morphologically and electrically characterized. It is observed that the hexagonal cadmium bromide exhibits large lattice mismatches with cubic Au substrates. The randomly distributed nano- rod like grains is accompanied with average surface roughness of ~26 nm. When an ac signal of low amplitude is imposed between the terminals of the Au/CdBr2/Au devices, a negative capacitance effect in the frequency domain of 10-1800 MHz is observed. In addition, analysis of the impedance spectra in the same domain has shown that the device behaves as band pass/stop filters suitable for 4G technology. The microwave based standard analysis of the Au/CdBr2/Au band filters have shown that it displays a notch ( f c o) frequency of 2.0 GHz. The cutoff frequency at f c o reaches 7.86 GHz. The features of the Au/CdBr2/Au devices nominate it for use as microwave resonators and as negative capacitance devices suitable for; 4G technology, noise reduction and for parasitic capacitance cancellation.