Metal-insulator-metal capacitor structures

摘要

Capacitor structures capable of providing both low-voltage capacitors and high-voltage capacitors are described herein. In one embodiment, a capacitor structure comprises a first electrode formed from a first metal layer, a second electrode formed from a second metal layer, and a third electrode formed from a third metal layer, wherein second and third electrodes are spaced farther apart than the first and second electrodes. The capacitor structure also comprises a first dielectric layer between the first and second electrodes, and a second dielectric layer between the second and third metal layers, wherein the second dielectric layer has a larger thickness than the first dielectric layer. The first electrode is coupled to a first power-supply rail, the third electrode is coupled to a second power-supply rail, and the second power-supply rail has a higher power-supply voltage than the first power-supply rail.

主权项

1. A capacitor structure, comprising:
a first electrode formed from a first metal layer; a second electrode formed from a second metal layer; a third electrode formed from a third metal layer, wherein the second and third electrodes are spaced farther apart than the first and second electrodes; a first dielectric layer between the first and second electrodes to form a first decoupling capacitor therebetween, wherein the first decoupling capacitor comprises a first capacitance and a first break down voltage; a second dielectric layer between the second and third metal layers to form a second decoupling capacitor therebetween, wherein the second decoupling capacitor comprises a second capacitance and a second break down voltage, wherein the second dielectric layer has a larger thickness than the first dielectric layer such that the first capacitance is greater than the second capacitance, and the first break down voltage is less than the second break down voltage; a fourth electrode formed from the first metal layer; a fifth electrode formed from the second metal layer; a sixth electrode formed from the third metal layer; a third dielectric layer between the fourth and fifth electrodes to form a third decoupling capacitor therebetween, wherein the third decoupling capacitor comprises a third capacitance and a third break down voltage; a fourth dielectric layer between the fifth and sixth metal lavers to form a fourth decoupling capacitor therebetween, wherein the fourth decoupling capacitor comprises a fourth capacitance and a fourth break down voltage, wherein the fourth dielectric layer has a larger thickness than the third dielectric layer such that the third capacitance is greater than the fourth capacitance, and the third break down voltage is less than the fourth break down voltage; wherein the first, fourth, and sixth electrodes are coupled to a first power-supply rail, the third electrode is coupled to a second power-supply rail, the second and fifth electrodes are coupled to a third power-supply rail, the second power-supply rail has a higher power-supply voltage than that of the first power-supply rail, and the third power-supply rail is coupled to ground.