Semiconductor structure having integrated inductor therein
A semiconductor structure includes: a substrate; a first passivation layer over the substrate; a second passivation layer over the first passivation layer; and a magnetic core in the second passivation layer; wherein the magnetic core includes a first magnetic material layer and a second magnetic material layer over the first magnetic material layer, the first magnetic material layer and the second magnetic material layer are separated by a high resistance isolation layer, and the high resistance isolation layer has a resistivity greater than about 1.3 ohm-cm.
1. A semiconductor structure, comprising:
a substrate;
a first passivation layer over the substrate;
a second passivation layer over the first passivation layer; and
a magnetic core in the second passivation layer;
wherein the magnetic core includes a first magnetic material layer and a second magnetic material layer over the first magnetic material layer, the first magnetic material layer and the second magnetic material layer are separated by a high resistance isolation layer, and the high resistance isolation layer has a resistivity greater than about 1.3 ohm-cm; and
wherein the magnetic core further comprises a metal layer between the high resistance isolation layer and the second magnetic material layer.
2. The semiconductor structure of claim 1 , wherein high resistance isolation layer includes Si 3 N 4 .
3. The semiconductor structure of claim 1 , wherein high resistance isolation layer includes AlN.
4. The semiconductor structure of claim 1 , wherein high resistance isolation layer includes Al 2 O 3 .
5. The semiconductor structure of claim 1 , wherein the metal layer includes tantalum (Ta).
6. The semiconductor structure of claim 1 , wherein the magnetic core further comprises a low resistance isolation layer on a top surface of the second magnetic material layer, and the low resistance isolation layer has a resistivity less than about 1.3 ohm-cm.
7. The semiconductor structure of claim 1 , wherein the magnetic core further comprises another high resistance isolation layer on a top surface of the second magnetic material layer, and the another high resistance isolation layer has a resistivity greater than about 1.3 ohm-cm.
8. A semiconductor structure, comprising:
a first passivation layer;
a second passivation layer over the first passivation layer;
a third passivation layer over the second passivation;
a lower coil segment in the first passivation layer;
an upper coil segment in the third passivation layer; and
a magnetic core in the second passivation layer and insulated from the lower coil segment and the upper coil segment;
wherein the magnetic core includes a first magnetic material layer and a second magnetic material layer over the first magnetic material layer, the first magnetic material layer and the second magnetic material layer are separated by a composite isolation layer including a high resistance isolation layer and a low resistance isolation layer, and the high resistance isolation layer has a resistivity greater than that of the low resistance isolation layer.
9. The semiconductor structure of claim 8 , wherein the high resistance isolation layer is over the low resistance isolation layer.
10. The semiconductor structure of claim 9 , wherein the high resistance isolation layer has a resistivity greater than about 1.3 ohm-cm, and the low resistance isolation layer has a resistivity less than about 1.3 ohm-cm.
11. The semiconductor structure of claim 8 , wherein the magnetic core further comprises a metal layer between the high resistance isolation layer and the second magnetic material layer.
12. The semiconductor structure of claim 8 , wherein the magnetic core further comprises a metal layer below a bottom surface of the first magnetic material layer.
13. The semiconductor structure of claim 8 , wherein the low resistance isolation layer includes oxide of the first magnetic material layer.
14. A semiconductor structure, comprising:
a first passivation layer;
a second passivation layer over the first passivation layer;
a third passivation layer over the second passivation;
a lower coil segment in the first passivation layer;
an upper coil segment in the third passivation layer; and
a magnetic core in the second passivation layer and insulated from the lower coil segment and the upper coil segment;
wherein the magnetic core from bottom to top includes a first magnetic material layer, a second magnetic material layer, a third magnetic material layer and a fourth magnetic material layer, the first magnetic material layer and the second magnetic material layer are separated by a first low resistance isolation layer, the second magnetic material layer and the third magnetic material layer are separated by a high resistance isolation layer, the third magnetic material layer and the fourth magnetic material layer are separated by a second low resistance isolation layer, and the high resistance isolation layer has a resistivity greater than that of the low resistance isolation layer.
15. The method of claim 14 , wherein the high resistance isolation layer has a resistivity greater than about 1.3 ohm-cm, and the low resistance isolation layer has a resistivity less than about 1.3 ohm-cm.
16. The semiconductor structure of claim 14 , wherein the first low resistance isolation layer includes oxide of the first magnetic material layer.
17. The semiconductor structure of claim 14 , wherein the second low resistance isolation layer includes oxide of the third magnetic material layer.
18. The semiconductor structure of claim 14 , wherein high resistance isolation layer includes Si 3 N 4 .
19. The semiconductor structure of claim 14 , wherein high resistance isolation layer includes AlN.
20. The semiconductor structure of claim 14 , wherein high resistance isolation layer includes Al 2 O 3 .