Thin-Film Capacitor

Abstract

A thin-film capacitor and a method for making the thin-film capacitor having a structure that can prevent vertical stress acting on outer connecting terminals, such as bumps, from concentrating on electrode layers, and capable of easily increasing the equivalent series resistance to a desired value. The thin-film capacitor includes a substrate, a capacitor unit disposed above the substrate and composed of at least one dielectric thin film and two electrode layers, a protective layer covering at least part of the capacitor unit, a lead conductor electrically connected to one of the electrode layers of the capacitor unit, and a bump disposed above the lead conductor. The lead conductor includes a connecting part disposed in an opening in the protective layer and electrically connected to one of the electrode layers of the capacitor unit, and a wiring part extending over the protective layer. The bump is disposed above the wiring part.

1 . A thin-film capacitor comprising:
 a substrate;   a capacitor unit disposed above the substrate and including at least one dielectric thin film and two electrode layers;   a protective layer covering at least part of the capacitor unit;   a lead conductor electrically connected to one of the electrode layers of the capacitor unit; and   an outer connecting terminal disposed above the lead conductor,   wherein the lead conductor includes a connecting part disposed in an opening in the protective layer and electrically connected to one of the electrode layers of the capacitor unit, and a wiring part extending over the protective layer; and the outer connecting terminal is disposed above the wiring part;   at least one sublayer of the protective layer is an organic insulator;   the wiring part is connected to a plurality of connecting parts;   the wiring part has at least one bent portion; and   the wiring part includes a first conductor line and a second conductor line connected to the first conductor line via the bent portion, and the first conductor line and the second conductor line are arranged such that a first length of the first conductor line is parallel to and adjacent to a second length of the second conductor line.   
     
     
         2 . The thin-film capacitor according to  claim 1 , further comprising:
 wherein the lead conductor is a first lead conductor electrically connected to a first electrode layer of the two electrode layers of the capacitor unit; and   a second lead conductor electrically connected to a second electrode layer of the two electrode layers of the capacitor unit, the second electrode layer having a potential different from that of the first electrode layer,   wherein the connecting part of the first lead conductor is a first connecting part electrically connected to the first electrode layer, and the wiring part is a first wiring part extending over the protective layer from the first connecting part in a direction away from the second lead conductor; and   the second lead conductor includes a second connecting part electrically connected to the second electrode layer, and a second wiring part extending over the protective layer from the second connecting part in a direction away from the first lead conductor.   
     
     
         3 . The thin-film capacitor according to  claim 2 , wherein a plurality of connecting parts of the lead conductor is electrically connected to one of the electrode layers of the capacitor unit. 
     
     
         4 . The thin-film capacitor according to  claim 1 , wherein a plurality of connecting parts of the lead conductor is electrically connected to one of the electrode layers of the capacitor unit.