Ultra thin vapor chamber for high precision electronic equipment

The wick structures are core components of the two-phase heat transfer devices, which provide the capillary force to drive the closed circulation of the working fluid and an interface for the liquid–vapour phase changes. The start-up and thermal performance of the heat pipes rely mainly on the wick structures.

The main difficulty of ultra-thin vapor chamber is the design of its capillary structure. Sufficient capillary structures need to be laid in a very small space to meet the rapid reflux of condensate working fluid. The capillary structure used by ultra-thin vapor chamber usually includes wire mesh structure, sintered powder structure, braided fiber, groove structure, etc.

The mesh structure has the characteristics of high porosity but low permeability, so that it has good temperature characteristics. The sintered powdery structure is characterized by high permeability but low porosity so that it has low thermal resistance. One or more capillary structures are generally used in ultra-thin vapor chamber to meet liquid reflux, but the increase of capillary structure will lead to the reduction of internal steam chamber to increase gas flow resistance, so the design of capillary structure becomes the key of ultra-thin vapor chamber.