Methods of fabricating passive element without planarizing and related semiconductor device
View Patent ↗Methods of fabricating a passive element and a semiconductor device including the passive element are disclosed including the use of a dummy passive element. A dummy passive element is a passive element or wire which is added to the chip layout to aid in planarization but is not used in the active circuit. One embodiment of the method includes forming the passive element and a dummy passive element adjacent to the passive element; forming a dielectric layer over the passive element and the dummy passive element, wherein the dielectric layer is substantially planar between the passive element and the dummy passive element; and forming in the dielectric layer an interconnect to the passive element through the dielectric layer and a dummy interconnect portion overlapping at least a portion of the dummy passive element. The methods eliminate the need for planarizing.
1. A method of fabricating a passive element, the method comprising:
forming the passive element and a dummy passive element adjacent to the passive element, wherein the dummy passive element substantially surrounds the passive element;
forming a first dielectric layer over the passive element and the dummy passive element, wherein the first dielectric layer is substantially planar over an area between the passive element and the dummy passive element; wherein the first dielectric layer forming includes forming a step in the first dielectric layer above an outer edge of the dummy passive element; and
forming a first interconnect to the passive element through the first dielectric layer and a dummy interconnect portion overlapping at least a portion of the dummy passive element, wherein the dummy interconnect portion forming includes forming an opening at the step in the first dielectric layer and depositing a conductive material into the opening to form the dummy interconnect portion.
2. The method of claim 1 , further comprising forming a second dielectric layer and a second interconnect to the first interconnect in the second dielectric layer without planarizing the first dielectric layer.
3. The method of claim 2 , further comprising forming a third and fourth dielectric layer over the second dielectric layer with the fourth dielectric layer including another passive element and another dummy passive element.
4. The method of claim 1 , wherein the dummy interconnect portion substantially surrounds the passive element.
5. The method of claim 4 , wherein the dummy interconnect portion overlaps the dummy passive element along substantially all of the dummy passive element.
6. The method of claim 1 , wherein the first interconnect includes a via to the passive element in the first dielectric layer that has substantially the same height as a via of another interconnect to a structure other than the passive element.
7. The method of claim 1 , wherein the dummy passive element is present in substantially all of the dielectric layer excepting where a via or the passive element exists.
8. The method of claim 1 , wherein the passive element is selected from the group consisting of: a thin-film resistor and a metal-insulator-metal capacitor.
9. A method of fabricating a passive element, the method comprising:
forming the passive element and a dummy passive element adjacent to the passive element, wherein the dummy passive element substantially surrounds the passive element;
forming a first dielectric layer over the passive element and the dummy passive element including forming a step in the first dielectric layer above an outer edge of the dummy passive element;
forming in the first dielectric layer a first interconnect to the passive element through the first dielectric layer and a dummy interconnect portion overlapping at least a portion of the dummy passive element; and
forming a second dielectric layer and a second interconnect to the first interconnect without planarizing the first dielectric layer.
10. A method of fabricating a passive element, the method comprising:
forming the passive element and a dummy passive element adjacent to the passive element, wherein the dummy passive element substantially surrounds the passive element;
forming a first dielectric layer over the passive element and the dummy passive element, wherein the first dielectric layer is substantially planar over an area between the passive element and the dummy passive element; wherein the first dielectric layer forming includes forming a step in the first dielectric layer above an outer edge of the dummy passive element; and
forming a first interconnect to the passive element through the first dielectric layer and a dummy interconnect portion overlapping at least a portion of the dummy passive element.