A thin-film multilayer high-Q inductor having a ferromagnetic core and
spanning at least three metal layers is formed by forming a plurality of
parallel first metal runners on the semiconductor substrate. A plurality
of first and second vertical conductive vias are formed in electrical
connection with each end of the plurality of metal runners. A plurality
of third and fourth conductive vias are formed over the plurality of
first and second conductive vias and a plurality of second metal runners
are formed interconnecting the plurality of third and fourth conductive
vias. The first metal runners and second metal runners are oriented such
that one end of a first metal runner is connected to an overlying end of
a second metal runner by way of the first and third vertical conductive
vias. The other end of the second metal runner is connected to the next
metal one runner by way of the second and fourth vertical conductive
vias., forming a continuously conductive structure having a generally
helical shape. An inductor core is formed by first forming a silicon
layer between each one of the plurality of first metal runners. A
germanium layer is formed thereover and the structure is annealed,
causing formation of quantum dots of germanium. A cobalt layer is then
formed over the quantum dots and another anneal process drives the cobalt
into the quantum dots, where it is captured to form the ferromagnetic
core.