Abstract
This invention proposes a method of constructing a microchannel heat pipe spreader or a microchannel loop heat pipe with an enclosing metal case. This method retains the advantages of both the metallic thermal devices and the microchannel thermal devices. The devices constructed in the said method are easy to evacuate, long-term vacuum-tight, having smaller pressure drop in liquid flow, and structurally stronger than pure silicon-based thermal devices. Also proposed are embodiments of microchannel heat pipe spreaders and microchannel loop heat pipes with the internal structure consisting of a wick evaporator and plates etched with microchannels. Microchannels are adopted to reduce the friction force on the liquid flow, so that dry-out in the evaporator may be avoided up to higher heat loads. To further reduce the friction force on liquid motion, an evaporator made of micro pin-array wick can be adopted. The said microchannel heat pipe spreaders can be easily integrated with fins and fans to serve as a cooling device. The said microchannel loop heat pipes can be easily keyed with traditional heat pipes into their metal walls of the flat-plate loop heat pipe to enhance the cooling capability. A part of the heat can then be transported to remote locations such as the outer shell, the keyboard, or other internal metal structures.