Electronic component and manufacturing method thereof
The invention provides an electronic component and a manufacturing method thereof that can achieve an improved adhesion strength when the electronic component is solder-mounted onto an external substrate and can thereby obtain considerably improved electric properties and reliabilities, etc. An electronic component, which is a capacitor 1 , has: a circuit element 5 a formed on a substrate 2 ; an electrode layer 5 b connected to the circuit element 5 a ; passivation layers 6 and 8 that cover the electrode layer 5 b ; and terminal electrodes 9 a and 9 b connected to the electrode layer 5 b via via-conductors Va and Vb formed through the passivation layers 6 and 8 , the terminal electrodes 9 a and 9 b being formed to cover the side wall of the passivation layers 6 and 8 . Since the pad electrodes 9 a and 9 b are formed so as to cover the passivation layers 6 and 8 across their uppermost surfaces and side walls, the area of contact between the pad electrodes 9 a and 9 b and the solder for solder-mounting increases, and the capacitor 1 can consequently exhibit an improved adhesion strength.
1. An electronic component comprising:
a lower electrode formed on a top surface of a substrate, the low electrode comprising a side wall and a top surface;
a dielectric layer that covers (1) the side wall, (2) a part of the top surface of the lower electrode, and (3) a part of the top surface of the substrate around the lower electrode;
a circuit element connected to the lower electrode;
an electrode layer formed on the dielectric layer;
a passivation layer that covers the electrode layer; and
a terminal electrode disposed on a top part of the passivation layer and connected to the electrode layer via a via-conductor formed through the passivation layer,
wherein:
the terminal electrode integrally extends from the top part of the passivation layer along a side wall of the passivation layer and also along an edge portion of the top surface of the substrate;
one end of the terminal electrode is located on the side wall of the passivation layer; and
a part of the edge portion is left uncovered.
2. The electronic component according to claim 1 , wherein the passivation layer includes: a first passivation layer formed above the substrate; and a second passivation layer formed on the first passivation layer and inside an area where the first passivation layer is formed.
3. The electronic component according to claim 2 , wherein the second passivation layer has a substrate side surface that faces the substrate and a terminal electrode side surface that faces the terminal electrode, the substrate side surface of the second passivation layer has a smaller area than the terminal electrode side surface of the second passivation layer; and the side wall of the passivation layer has a reverse-tapered surface.
4. The electronic component according to claim 1 , wherein the electronic component is a capacitor.
5. A method for manufacturing an electronic component, comprising the steps of:
forming a lower electrode on a top surface of a substrate, the low electrode comprising a side wall and a top surface;
forming a dielectric layer that covers (1) the side wall, (2) a part of the top surface of the lower electrode, and (3) a part of the top surface of the substrate around the lower electrode;
forming a circuit element connected to the lower electrode;
forming an electrode layer on the dielectric layer;
forming a passivation layer that covers the electrode layer;
forming a via-conductor that extends through the passivation layer; and
disposing a terminal electrode so that the terminal electrode is connected to the electrode layer via the via-conductor and integrally extends from a top part of the passivation layer along a side wall of the passivation layer and also along an edge portion of the top surface of the substrate;
wherein:
one end of the terminal electrode is located on the side wall of the passivation layer; and
a part of the edge portion is left uncovered.