Manufacturing method of metal structure in multi-layer substrate and structure thereof
Disclosed is a manufacturing method of metal structure in multi-layer substrate and structure thereof. The manufacturing method of the present invention comprises following steps: coating at least one photoresist layer on a surface of a dielectric layer, and then exposing the photoresist dielectric layer to define a predetermined position of the metal structure; therefore, removing the photoresist layer at the predetermined position and forming the metal structure at the predetermined position before forming at least one top-cover metal layer on a surface of the metal structure. The present invention can form a cover metal layer covering over the top surface and the two side surfaces, even the under surface of the metal structure, by one single photomask. Moreover, a finer metal structure with higher reliability can be manufactured. Furthermore, a metal structure can be used as a coaxial structure is also realized.
1. A metal structure in a multi-layer substrate, comprising:
a metal structure, positioned at a predetermined position on a dielectric layer;
a top-cover metal layer, positioned at a top surface of the metal structure and covered two side surfaces of the metal structure;
an under-cover metal layer, positioned at an under surface of the metal structure;
a top-cover dielectric layer, formed between the metal structure and the top-cover metal layer; and
an under-cover dielectric layer, formed between the metal structure and the under-cover metal layer, wherein the dielectric layer at the predetermined position is a concave structure.
2. The metal structure of claim 1 , wherein the material of the dielectric layer is polyimide.
3. The metal structure of claim 1 , wherein the material of the metal structure is copper.
4. The metal structure of claim 1 , wherein the material of the top-cover metal layer is selected from chromium, titanium, gold, platinum and nickel.