Title :
Gate-assisted high-Q-factor junction varactor
Author :
Gau, J.-H. ; Wu, R.-T. ; Sang, Steven ; Kuo, C.-H. ; Chang, T.-L. ; Chen, H.-H. ; Chen, Anchor ; Ko, Joe
Author_Institution :
Central R&D Group, United Microelectron. Corp., Hsinchu, Taiwan
Abstract :
In this letter, we demonstrate a high-performance gate-assisted junction varactor. The gate plays an important role in the varactor; it can decrease the series resistance and enlarge the junction capacitance of this device. With the assistance of a positive-biased gate, the Q-factor of a varactor with 723 fF capacitance at 2.4 GHz is as high as 108. Its tuning ratio is 30.1% when it is operated in the range of 0.5 to 2.5 V.
Keywords :
CMOS integrated circuits; Q-factor; junction gate field effect transistors; varactors; 0.5 to 2.5 V; 2.4 GHz; 723 fF; gate-assisted junction varactor; high-Q-factor junction varactor; junction capacitance; series resistance; tuning ratio; Capacitance; Circuit optimization; Electrical resistance measurement; P-n junctions; Phase locked loops; Radio frequency; Tuning; Varactors; Voltage; Voltage-controlled oscillators; tuning ratio; varactor;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2005.853642
