Probe sheet with contact tip on stacked multi-layer and method of manufacturing the same

A method of manufacturing a probe sheet with a multi-layer contact tip, the method comprising:

• (a) forming a seed layer including a titanium/copper (Ti/Cu) layer and a Cu layer on an upper portion of a polyimide layer of a base substrate;
• (b) laminating a polyimide film on an upper portion of the seed layer, which is formed in step (a), in a vacuum atmosphere to form a first polyimide layer and forming an etching hole on a film surface thereof;
• (c) forming a ground line layer by a process of forming a Ti/Cu layer on the etching hole using high-temperature sputtering and forming a Cu layer with a predetermined thickness thereon using electroplating;
• (d) laminating a polyimide film on upper portions of the first polyimide layer and the ground line layer in a vacuum atmosphere to form a second polyimide layer and forming an etching hole and a connecting hole on a film surface thereof;
• (e) forming a circuit line layer by a process of forming a Ti/Cu layer on the etching hole using high-temperature sputtering and forming a Cu layer with a predetermined thickness thereon using electroplating;
• (f) laminating a polyimide film on upper portions of the second polyimide layer and the circuit line layer in a vacuum atmosphere to form a third polyimide layer and forming an etching hole and a connecting hole on a film surface thereof;
• (g) forming a base bump layer by a process of forming a Ti/Cu layer on the etching hole using high-temperature sputtering and forming a nickel-cobalt (Ni—Co) alloy layer with a predetermined thickness thereon using electroplating and molding processes;
• (h) forming a first contact tip layer as a Ni—Co alloy layer with a predetermined thickness on an upper portion of the base bump layer;
• (i) forming a second contact tip layer as a Ni—Co alloy layer with a predetermined thickness on an upper portion of the first contact tip layer;
• (j) forming a protective layer by etching a portion around the second contact tip layer exposed using an etching groove for coating the second contact tip layer and coating an outer surface of the second contact tip layer with rhodium using electroplating;
• and
• (k) removing the base substrate, the polyimide layer, and the seed layer at the bottom using a laser.