Method for drilling micro-hole and structure thereof

A method for making a micro-hole structure, comprising the steps of:

• (a) providing a substrate having a first surface and a second surface;
• (b) projecting a first stage working energy source carrying a predetermined first stage working energy onto a predetermined drilling site on the first surface of the substrate;
• (c) melting a portion of the substrate at the drilling site with the first stage working energy source in a predetermined period of time of projection of the first stage working energy source to thereby form a working energy entering section in the substrate next to the first surface until the first stage working energy source penetrates through the second surface of the substrate to form a micro-hole that extends through both the first and second surfaces of the substrate;
• (d) projecting a second stage working energy source carrying a predetermined second stage working energy different from that of the first stage working energy source onto the micro-hole;
• and
• (e) allowing a melt formed by melting a portion of the substrate in the micro-hole next to the second surface with the second stage working energy source to reflow in a direction opposite to the projection of the second stage working energy source to thereby form a reflow section in the micro-hole next to the second surface of the substrate, also defining a second opening in the second surface of the substrate, and forming a through hole section between the working energy entering section and the reflow section with the reflow section extending from the second opening to and in communication with the through hole section and having a bore diameter converging from the second opening toward the through hole section.