Inductor with a decreased surface area and an improved ability to conduct strong currents
An inductor formed in a stacking of insulating layers. The inductor comprises first and second access terminals, at least first and second interlaced loops on a first level, and at least third and fourth interlaced loops on a second level distinct from the first level. The third loop is the symmetrical of the first loop with respect to a plane. The fourth loop is the symmetrical of the second loop with respect to said plane. The internal ends of the first and second loops are connected to the internal ends of the third and fourth loops. The external ends of the first and third loops are connected to the first and second access terminals. The external ends of the second and fourth loops are interconnected.
1. An inductor formed in a stacking of insulating layers, the inductor comprising:
first and second access terminals,
at least first and second interlaced loops on a first level (N 1 ), and
at least third and fourth interlaced loops on a second level (N 2 ) distinct from the first level,
the third loop being, as seen along the stacking direction, symmetrical with the first loop with respect to a plane (P′) and
the fourth loop being, as seen along the stacking direction, symmetrical with the second loop with respect to said plane,
internal ends of the first and second loops being connected to internal ends of the third and fourth loops,
external ends of the first and third loops being connected to the first and second access terminals, and
the external ends of the second and fourth loops being interconnected.
2. The inductor of claim 1 , comprising a midpoint (M′) at a junction connecting the external end of the second and fourth loops.
3. The inductor of claim 1 , wherein
the first loop comprises a first internal end and a second external end,
the second loop comprising a third internal end and a fourth external end and
the third loop comprising a fifth internal end and a sixth external end and
the fourth loop comprises a seventh internal end and an eighth external end and wherein
the first end is connected to the seventh end,
the second end being connected to the first access terminal,
the third end being connected to the fifth end,
the fourth end being connected to the eight end and
the sixth end being connected to the second access terminal.
4. The inductor of claim 3 ,
wherein the fourth end of the second loop is located opposite to the first access terminal with respect to the center of the inductor and
wherein the eighth end of the fourth loop is located opposite to the second access terminal with respect to the center of the inductor.
5. The inductor of claim 1 , comprising metal tracks of at least one first and one second metallization level (M 4 , M 5 ), the inductor further comprising:
in the first metallization level (M 4 ):
a first portion forming a first half-loop and connected to the first access terminal;
a second portion forming a second half-loop and connected to the first portion;
a third portion forming, a third half-loop, symmetrical to the first portion with respect to said plane (P′) and extending along the external edge of the second portion and
a fourth portion forming a fourth half-loop, symmetrical to the second portion with respect to said plane, the first portion extending along the external edge of the fourth portion; and
in the second metallization level (M 5 ):
a fifth portion forming a fifth half-loop and connected to the second access terminal;
a sixth portion forming a sixth half-loop and connected to the fifth portion;
a seventh portion forming a seventh half-loop, symmetrical to the fifth portion with respect to said plane and extending along the external edge of the sixth portion; and
an eighth portion forming an eighth half-loop, symmetrical to the sixth portion with respect to said plane, the fifth portion extending along the external edge of the eighth portion.
6. The inductor of claim 5 , wherein
the first portion is, along the stacking direction, aligned with the seventh portion,
the second portion being aligned with the eighth portion,
the third portion ( 146 ) being aligned with the fifth portion, and
the fourth portion ( 148 ) being aligned with the sixth portion.
7. The inductor of claim 5 ,
wherein the second portion is connected to a first rectilinear portion extending along said plane (P′), on one side of said plane, all the way to the central portion of the inductor and
wherein the fourth portion is connected to a second rectilinear portion extending along said plane, on the side opposite to said plane, all the way to the central portion of the inductor.
8. The inductor of claim 1 , wherein a metallization level (M 1 -M 7 ) from among several metallization levels is associated with each insulating layer, at least one of a first half-loop and a second half-loop comprising at least two tracks of different metallization levels aligned along the stacking direction of the insulating layers and connected to each other along their entire length.
9. An electronic device, comprising an inductor formed in a stacking of insulating layers, the inductor comprising:
first and second access terminals,
at least first and second interlaced loops on a first level (N 1 ), and
at least third and fourth interlaced loops on a second level (N 2 ) distinct from the first level,
the third loop being, as seen along the stacking direction, symmetrical with the first loop with respect to a plane (P′) and
the fourth loop being, as seen along the stacking direction, symmetrical with the second loop with respect to said plane,
internal ends of the first and second loops being connected to internal ends of the third and fourth loops,
external ends of the first and third loops being connected to the first and second access terminals, and
the external ends of the second and fourth loops being interconnected.
10. The electronic device of claim 9 , wherein the inductor is formed in an integrated circuit.