Patent ID: 6420773
Filing Date: 2002-07-16
Classification: H01L

Abstract:
A high inductance and high-Q monolithic inductor structure for RF application fabricated by using a multilevel interconnect technology of m conducting levels, wherein m is a nature number larger than 4, comprising:a first insulator formed on a substrate of said inductor structure; a first metal level used as a conducting cross-under line formed on said first insulator and then a second insulator formed on said first insulator and said first metal level; a first spiral coil with N1 turn fabricated by a second metal level and formed on said second insulator over said first metal level and then a third insulator formed on said second insulator and said second metal level; a second spiral coil with N2 turn fabricated by a third metal level, formed on said third insulator over said first spiral coil and positioned with reflection and rotation transformations with respect to the center of said first spiral coil and then a fourth insulator formed on said third insulator and said third metal level; a third spiral coil with N3 turn fabricated by a fourth metal level, formed on said fourth insulator over said second spiral coil and positioned with reflection and rotation transformations with respect to the center of said first spiral coil and then a fifth insulator formed on said fourth insulator and said fourth metal level; and an edge end terminal of said first spiral coil connected to an edge end terminal of said second spiral coil through a first via plug and a central end terminal of said second spiral coil connected to a central end terminal of said third spiral coil through a second via plug, wherein N1, N2 and N3 are nature numbers and not smaller than 3 (&lE;3) and said conducting cross-under line is connected between a first pad and said first spiral coil, thereby said first, second and third spiral coils include current flows in the same direction.