Thin-film capacitor element and electronic circuit board on which thin-film capacitor element is formed
AssigneeAlps Electric Co., Ltd.
InventorsShinji Murata, Ken Yamamura, Mitsuru Tokuta
Life of this patent
Estimating the term…
Abstract
In order to provide an electronic circuit board capable of preventing the breakdown voltage of a capacitor element from dropping and excellent in high frequency performance, a positive type photoresist is spin-coated over the surface of an alumina substrate and is exposed to light and developed to form an insulating layer partially, followed by formation of a capacitor element by successively stacking a lower electrode, a dielectric layer and an upper electrode over this insulating layer, further followed by formation of a resistance element, an inductor element and a transmission line, each in a filmy state, over the surface of the alumina substrate.
Claims6
A thin-film capacitor element comprising:
- a substrate;
- a lower electrode disposed above the substrate;
- a dielectric layer disposed above the lower electrode;
- an insulating layer covering a periphery of the dielectric layer, the insulating layer having an opening and comprising a photosensitive resist;
- and
- an upper electrode formed over the insulating layer and stacked over the dielectric layer within the opening.
An electronic circuit board substrate comprising:
- a substrate;
- an insulating layer formed over part of the substrate, the insulating layer comprising a photosensitive polymer film;
- a capacitor element having a lower electrode, a dielectric layer and an upper electrode stacked successively over the insulating layer;
- and
- at least an inductor element and a transmission line formed, each as a thin film, over the substrate,
- wherein the lower electrode and upper electrode overlap each other within a boundary formed by the insulating layer.
Dependencies are inferred from the claim text.