Titanium-based thermal ground plane

A thermal ground plane, comprising:

• a wicking structure on a titanium substrate, the wicking structure comprising a plurality of microfabricated structures etched into the titanium substrate, wherein a pitch of the microfabricated structures is a distance from a center of one microfabricated structure to a center of a next neighboring microfabricated structure, and the microfabricated structures comprise titanium;
• a vapor cavity in communication with the wicking structure;
• a fluid contained within the wicking structure and the vapor cavity for transporting thermal energy between a hotter region of the thermal ground plane and a colder region of the thermal ground plane, wherein the hotter region is hotter than the colder region, the fluid is driven by capillary forces within the wicking structure, and the fluid comprises a liquid phase and a vapor phase;
• and
• the pitch of the microfabricated structures in a range between 5-500 micrometers, wherein the microfabricated structures include an etched roughness in a range of 1-1000 nanometers that enhances wetting performance of the wicking structure.