Method and device for an integrated trench capacitor
A methodology for forming trench capacitors on an interposer wafer by an integrated process that provides high-capacitance, ultra-low profile capacitor structures and the resulting device are disclosed. Embodiments include forming a polymer block on a front side of an interposer wafer, patterning and etching the polymer block to form one or more trenches, and forming a capacitor on an upper surface of the polymer block and in the one or more trenches.
1. A device comprising:
a polymer block on a front surface of an interposer wafer;
a capacitor formed on an upper surface of and in one or more trenches in the polymer block;
a first metal layer in the one or more trenches and on the upper surface of the polymer block; and
a dielectric layer on the first metal layer and side surfaces of the polymer block.
2. The device according to claim 1 , wherein the first metal layer is pulled back from outer edges of the polymer block.
3. The device according to claim 2 , further comprising:
a connection pad on the interposer wafer; and
a second metal layer on the connection pad and on the dielectric layer.
4. The device according to claim 1 , wherein the one or more trenches comprise one or more holes or one or more troughs in the polymer block.
5. The device according to claim 1 , wherein the one or more trenches have an aspect ratio of 1:20 to 1:25.
6. The device according to claim 1 , wherein the polymer layer is formed to a thickness of up to 100 micrometers (μm).
7. The device according to claim 3 , wherein the first and second metal layers each have a thickness of 100 to 500 nm.
8. The device according to claim 7 , wherein the first and second metal layers comprise copper (Cu) or aluminum (Al).
9. A device comprising:
a polymer block on a front surface of an interposer wafer;
a first metal layer formed in one or more trenches in the polymer block;
a dielectric layer formed over the first metal layer; and
a capacitor formed on an upper surface of and in the one or more trenches,
wherein the first metal layer is pulled back from outer edges of the polymer block, and
wherein the dielectric layer is formed on the first metal layer and side surfaces of the polymer block.
10. The device according to claim 9 , further comprising:
a connection pad on the interposer wafer; and
a second metal layer on the connection pad and on the dielectric layer.
11. The device according to claim 9 , wherein the one or more trenches comprise one or more holes or one or more troughs in the polymer block.
12. The device according to claim 9 , wherein the one or more trenches have an aspect ratio of 1:20 to 1:25.
13. The device according to claim 9 , wherein the polymer layer is formed to a thickness of up to 100 micrometers (μm).
14. The device according to claim 10 , wherein the first and second metal layers each have a thickness of 100 to 500 nm.
15. The device according to claim 14 , wherein the first and second metal layers comprise copper (Cu) or aluminum (Al).
16. A device comprising:
a polymer block on a front surface of an interposer wafer;
a connection pad on the interposer wafer;
a first metal layer formed in trenches in the polymer block;
a dielectric layer formed over the first metal layer;
a second metal layer on the connection pad and on the dielectric layer; and
a capacitor formed on an upper surface of and in the trenches of the polymer block,
wherein the trenches have an aspect ratio of 1:20 to 1:25, and
wherein the first metal layer is pulled back from outer edges of the polymer block.