Heat sink

A heat sink comprising:

• a base cover having an external wall extending upwards and outwards from a peripheral fringe thereof;
• a cover member having a skirt portion extending downwards and outwards from a peripheral fringe thereof, a plurality of through holes, and a plurality of internal walls respectively extending upwards from a peripheral fringe of said through hole, said cover member being mounted on said base member, said skirt portion being located within said external wall, a vapor chamber being defined between said base member and said cover member;
• at least one capillary layer having at least one plate member and a plurality of convex portions located on said plate member, said capillary layer being mounted in said vapor chamber, said convex portions dividing said vapor chamber into a plurality of flow passages in communication with one another, said capillary layer being spaced apart from said skirt portion at a predetermined distance;
• a plurality of hollow columns respectively having an opening at an end thereof and a capillary pipe fitted inside thereof, said hollow columns being identical to said through holes in numbers and being respectively fitted onto said internal wall at said opening thereof, each said capillary pipe having a bottom end extending into said vapor chamber and connected with said capillary layer, said capillary pipe having a plurality of pores at the bottom end thereof for intercommunicating said through holes and said flow passages, a position that an inner periphery of said hollow column contacts a top fringe of said internal wall being spaced apart from said capillary pipe at a predetermined distance;
• a plurality of cooling fins fitted around outer peripheries of said hollow columns and spaced apart from one another at a predetermined distance;
• and
• a predetermined amount of solder filling between said skirt portion and said base member and between said bottom sides of said hollow columns and said cover member.