Continuously Tunable Resonator Using a Novel Triangular Doped Area on a Silicon Substrate

• Published in: IEEE microwave and wireless components letters 2018-12, Vol.28 (12), p.1095-1097
• Main Authors: Allanic, Rozenn, Le Berre, Denis, Quere, Yves, Quendo, Cedric, Chouteau, David, Grimal, Virginie, Valente, Damien, Billoue, Jerome
• Format: Article
• Language: English
• Subjects: Active filters; Bias; Co-design; Electric potential; Electronics; Engineering Sciences; Junctions; p-i-n diode; PIN photodiodes; Resonant frequencies; Resonators; Short circuits; Silicon; silicon (Si) devices; Silicon substrates; Substrates; Tunable circuits and devices; tunable resonators
• ISSN: 1531-1309; 2771-957X; 1558-1764; 2771-9588
• DOI: 10.1109/LMWC.2018.2877661

This letter presents a continuously tunable resonator with a novel triangular doped area on a silicon substrate. The resonator and its tunable element (an n + pp + junction) are co-designed in the same flow, leading to new tradeoffs and novel behaviors. The co-design flexibility allows the active area to be drawn with any doping shape. The base of the triangular doped area is located at the end of a stub. Consequently, when the junction is forward biased with a low bias voltage, the resonator is ended by a short circuit at the triangle base. Then, by increasing the voltage, the short-circuit plan moves continuously until it reaches the top of the triangle, thereby decreasing the length of the short-circuited stub. Besides, a demonstrator validates the concept and offers a continuous resonant frequency tunability of 50%, from 2.2 to 3.3 GHz, with a bias voltage from 0 to −1.3 V.