Electronic component mounting structure and method for manufacturing the same

1. An electronic component mounting structure comprising:

an electronic component provided with an electrode terminal; and

a mounting substrate provided with a connector terminal which is positioned facing the electrode terminal,

wherein the electrode terminal is connected to the connector terminal via a protrusion electrode disposed on the electrode terminal or the connector terminal, and

wherein the protrusion electrode includes at least a conductive filler and a photosensitive resin, and

wherein a resin component crosslink density of the photosensitive resin is lower on an electrode terminal side of the protrusion electrode than on a connector terminal side of the protrusion electrode.

2. The electronic component mounting structure of claim 1 , wherein the conductive filler is subjected to fusion-adhering at a portion where the resin component crosslink density is low, and the conductive filler is subjected to contacting with each other at a portion where the resin component crosslink density is high, to make a connection between the electrode terminal and the connector terminal.

3. The electronic component mounting structure of claim 1 , wherein the resin component crosslink density continuously varies in a height direction of the protrusion electrode.

4. The electronic component mounting structure of claim 1 , wherein the protrusion electrode is formed of a plurality of layers different from each other in the resin component crosslink density of the photosensitive resin.

5. The electronic component mounting structure of claim 4 , wherein thickness of a first layer at least being in contact with the electrode terminal with respect to the plurality of layers varies with positions of the electrode terminal.

6. The electronic component mounting structure of claim 1 , wherein the protrusion electrode is formed of a plurality of protrusion electrode portions.

7. The electronic component mounting structure of claim 1 , wherein the protrusion electrode is provided with conductive film on the surface thereof.

8. The electronic component mounting structure of claim 1 , wherein the electronic component has a plurality of electrode terminals, and the mounting substrate has a plurality of connector terminals positioned facing the electrode terminals,

wherein the electrode terminals are connected to the connector terminals, respectively, via protrusion electrodes, and each protrusion electrode is disposed on the respective electrode terminal or the respective connector terminal,

wherein each protrusion electrode includes at least a conductive filler and a photosensitive resin, and

wherein, in each protrusion electrode, a resin component crosslink density of the photosensitive resin is lower on the electrode terminal side of the protrusion electrode than on the connector terminal side of the protrusion electrode.

9. The electronic component mounting structure of claim 8 , wherein the conductive filler of each protrusion electrode includes a plurality of particles, and

wherein, in each protrusion electrode, the particles are fusion-adhered to each other on the connector terminal side of the protrusion electrode and the particles contact each other on the electrode terminal side of the protrusion electrode.

10. The electronic component mounting structure of claim 1 , wherein the conductive filler includes a plurality of particles, and

wherein the particles are fusion-adhered to each other on the connector terminal side of the protrusion electrode, and the particles contact each other on the electrode terminal side of the protrusion electrode.