Integrated RC architecture, and methods of fabrication thereof
RC architectures are provided that include a substrate provided with a capacitor having a thin-film top electrode portion at a surface of the substrate on one side thereof. The resistance provided in series with the capacitor is controlled by providing a contact plate, spaced from the thin-film top electrode portion, and a set of plural bridging contacts extending between, and electrically interconnecting, the thin-film top electrode portion and the contact plate. Different resistance values can be set by appropriate selection of the number of bridging contacts. The capacitor can be a three-dimensional capacitor and contacts are then provided on respective first and second sides of the substrate, which face each other in the thickness direction of the substrate.
1 . An integrated RC component comprising:
a substrate including a first surface on a first side and a second surface on a second side, the second side of the substrate opposite to the first side, the second side located below first side, wherein the first surface and the second surface are on separate flat planes, wherein the second surface is uniformly flat;
a capacitor having a thin-film top electrode portion at the first surface on the first side of the substrate;
an insulating layer arranged above the thin-film top electrode portion of the capacitor;
a contact plate provided above and around the insulating layer;
a set of plural bridging contacts traversing the insulating layer and electrically connecting the thin-film top electrode portion of the capacitor to the contact plate, the bridging contacts being evenly distributed across a surface of the thin-film top electrode portion of the capacitor in a grid formation; and
first and second contacts arranged, respectively, on the first side of the substrate and on the second side of the substrate opposite to said first side, wherein the second contact is located below the second side and on the second surface of the substrate,
wherein the first contact comprises the contact plate, and a series RC circuit is formed between the first and second contacts.
2 . The RC component according to claim 1 , wherein the substrate is a low ohmic semiconductor substrate doped to contribute no more than 5% to resistance of the RC component.
3 . The RC component according to claim 1 , wherein the bridging contacts are distributed evenly across the surface of the thin-film top electrode portion of the capacitor.
4 . The RC component according to claim 2 , wherein the capacitor is a 3D capacitor, the substrate is a low ohmic semiconductor substrate and a bottom electrode of the 3D capacitor is formed by the low ohmic semiconductor substrate.
5 . The RC component according to claim 1 , wherein the bridging contacts comprise a material having a conductivity greater than that of a material forming the top capacitor electrode.
6 . The RC component according to claim 5 , wherein the bridging contacts and the contact plate are integrally formed of a same material.
7 . The RC component according to claim 1 , wherein the capacitor is a 3D capacitor comprising a stack of MIM (metal-insulator-metal) layers formed in pores of a porous anodic oxide region in the substrate.
8 . The RC component according to claim 1 , wherein the thin-film top electrode portion of the capacitor comprises polysilicon.
9 . The RC component according to claim 1 , wherein, in a thickness direction of the thin-film top electrode portion of the capacitor, a length of the bridging contacts is greater than a thickness of the thin-film top electrode portion.
10 . The RC component according to claim 1 , wherein the top electrode portion of the capacitor has a square peripheral shape.
11 . The RC component according to claim 1 , wherein the contact plate and the top electrode portion of the capacitor have at least one of a same peripheral shape and a same size.
12 . The RC component according to claim 1 , wherein only a part of the capacitor top electrode to be located at the first surface on the first side of the substrate is a single planar sheet forming said thin-film top electrode portion.
13 . A method of controlling a resistance of the RC component according to claim 1 , the method comprising:
acquiring a target value for the resistance of the RC component, and
setting a number of bridging contacts dependent on the acquired target resistance value.
14 . The method of claim 13 , further comprising:
acquiring a target current-handling capacity of the RC component;
setting a cross-sectional area and a length of the bridging contacts based on the target current-handling capacity; and
setting the number of bridging contacts based on the set cross-sectional area and length of the bridging contacts as well as on the acquired target resistance value.