Semiconductor structure and method for forming the same and semiconductor device

A semiconductor device, comprising:

• a semiconductor substrate;
• an insulating layer disposed over the semiconductor substrate;
• a conductive feature disposed in the insulating layer, wherein a top surface of the conductive feature is adjacent to a top surface of the insulating layer;
• an anisotropic conductive structure disposed on the insulating layer and the conductive feature, wherein the anisotropic conductive structure comprises:
• a porous metal oxide layer having a first nano-through-hole array exposing the top surface of the conductive feature and a second nano-through-hole array exposing the top surface of the insulating layer;
• and
• conductive pillars filling the first nano-through-hole array, wherein the conductive pillars are in contact with the top surface of the conductive feature;
• and
• a circuit substrate, wherein the circuit substrate has bonding pads on it, wherein the bonding pads are in contact with the conductive pillars.

A method for forming a semiconductor structure, comprising:

• providing a semiconductor substrate;
• forming a conductive pad over the semiconductor substrate;
• forming an insulating layer on the conductive pad, wherein the insulating layer has an opening to expose the conductive pad;
• forming a metal layer on the insulating layer, wherein the metal layer is formed through the opening and in contact with the conductive pad;
• performing an anodizing process cycle on the metal layer to oxidize a portion of the metal layer on the insulating layer to form a porous metal oxide layer, wherein the porous metal oxide layer has a first nano-through-hole array exposing the metal layer that is unoxidized and a second nano-through-hole array exposing the insulating layer;
• and
• performing a selective deposition process to form conductive pillars filling the first nano-through-hole array.