Liquid cooling device and manufacturing method thereof

A liquid cooling device, comprising:

• a thermally conductive base, having a fluid chamber and a plurality of fins, wherein the plurality of fins are located in the fluid chamber and protrudes from an inner surface of the thermally conductive base facing the fluid chamber, every two of the plurality of fins located adjacent to each other define a channel therebetween, distal ends of at least adjacent three of the plurality of fins located away from the inner surface together form a covering structure integrally formed as one piece with the at least adjacent three of the plurality of fins, and the covering structure partially covers the channel and extends between the at least adjacent three of the plurality of fins, the covering structure has an opening in fluid communication with the channel;
• a cover, having an inlet and an outlet, wherein the cover is mounted on the thermally conductive base and covers the fluid chamber, and the inlet is in fluid communication with the outlet via the fluid chamber;
• and
• a metallic partition, located between and welded to the covering structure and the cover.