Title :
Capacitance estimation of PN varactors based on unit cells
Author :
Marrero-Martín, M. ; González, B. ; García, J. ; Hernández, A.
Author_Institution :
Inst. for Appl. Microelectron., Univ. de Las Palmas de Gran Canaria
Abstract :
Integrated varactors are key elements in radio frequency integrated circuits. In this paper, several structures of varactors, based on p-n junction cells, are considered. A capacitance model is required to use these structures in a CAD environment. We have developed a model which considers area and perimeter capacitances of adjacent unit cells so as the reverse voltage dependence. Tuning ranges and quality factors are all well estimated. This model is applied to four varactors and their respective unit cells fabricated with AMS SiGe 0.35 mum technology. Modeled values are compared with measurements and the error between our estimations and measurements are smaller than 7% in all cases.
Keywords :
Ge-Si alloys; Q-factor; capacitance; p-n junctions; semiconductor materials; varactors; CAD environment; Si-Ge; capacitance model; integrated varactors; p-n junction cells; quality factors; radio frequency integrated circuits; reverse voltage; Anodes; Capacitance measurement; Circuit optimization; Geometry; Germanium silicon alloys; Q factor; Radiofrequency integrated circuits; Silicon germanium; Varactors; Voltage;
Conference_Titel :
Electron Devices, 2009. CDE 2009. Spanish Conference on
Conference_Location :
Santiago de Compostela
Print_ISBN :
978-1-4244-2838-0
Electronic_ISBN :
978-1-4244-2839-7
DOI :
10.1109/SCED.2009.4800536
