TY - GEN
T1 - Wafer-level fabrication of power inductors in silicon for compact dc-dc converters
AU - Li, Jiping
AU - Tseng, Victor Farm Guoo
AU - Xiao, Zhiming
AU - Xie, Huikai
N1 - Publisher Copyright:
© 2014TRF.
PY - 2014
Y1 - 2014
N2 - This paper reports the design, fabrication and characterization of a novel power inductor embedded inside a silicon substrate and fabricated at wafer level. Such power inductors in silicon (PIiS) fully explore the capability of forming high-aspect-ratio silicon molds by DRIE for large-cross-section copper winding plating (as thick as the silicon wafers) while also utilizing high-resistivity magnetic composites. By completely using electroplating processes to form the copper coils and vias, the contact resistance between conductive layers can be minimized, and the quality factor can be improved significantly. This process also provides surface mounting pads for a compact converter assembly. Square shaped spiral inductors (3×3×0.83mm3) were successfully fabricated, achieving a large inductance (430 nH), low DC resistance (84 mΩ), and high quality factor (21) at 6 MHz. The fabricated inductors were also assembled with a TI TPS62621 buck converter IC, and an efficiency of 83% was achieved.
AB - This paper reports the design, fabrication and characterization of a novel power inductor embedded inside a silicon substrate and fabricated at wafer level. Such power inductors in silicon (PIiS) fully explore the capability of forming high-aspect-ratio silicon molds by DRIE for large-cross-section copper winding plating (as thick as the silicon wafers) while also utilizing high-resistivity magnetic composites. By completely using electroplating processes to form the copper coils and vias, the contact resistance between conductive layers can be minimized, and the quality factor can be improved significantly. This process also provides surface mounting pads for a compact converter assembly. Square shaped spiral inductors (3×3×0.83mm3) were successfully fabricated, achieving a large inductance (430 nH), low DC resistance (84 mΩ), and high quality factor (21) at 6 MHz. The fabricated inductors were also assembled with a TI TPS62621 buck converter IC, and an efficiency of 83% was achieved.
UR - http://www.scopus.com/inward/record.url?scp=85012281285&partnerID=8YFLogxK
U2 - 10.31438/trf.hh2014.109
DO - 10.31438/trf.hh2014.109
M3 - Conference contribution
AN - SCOPUS:85012281285
T3 - Technical Digest - Solid-State Sensors, Actuators, and Microsystems Workshop
SP - 407
EP - 410
BT - 2014 Solid-State Sensors, Actuators and Microsystems Workshop, Hilton Head 2014
A2 - Allen, Mark G.
A2 - Mehregany, Mehran
PB - Transducer Research Foundation
T2 - 2014 Solid-State Sensors, Actuators and Microsystems Workshop, Hilton Head 2014
Y2 - 8 June 2014 through 12 June 2014
ER -