Characterization of Ultra-Thin Vapor Chambers for Notebook Computer Applications

Thermal management of mobile computing devices are critical to enhance user experience. Two vectors for user experience are-laptop surface temperature control in steady state workload and transient chip temperature control in bursty workload. Thermal solutions that enhance spreading in lateral direction and at the same time carry large quantities of heat from chip are needed to satisfy above two vectors. Vapor chambers are solutions that have traditionally been used in laptop industry for some time. However, their thicknesses are in the range of 0.5 mm and above, below which performance is strained. In this paper, we study an ultra-thin 0.3 mm vapor chamber that can be used in super slim competitive form factors such as tablets and premium laptops. Detailed component level experimental study is conducted using a standard characterization methodology. Figures of merit include steady state in-plane resistance, maximum steady state heat transfer capability and maximum transient heat transfer capability. We also specifically study the performance using both a uniform heater and a high-power density chip replicating actual processor considering different flow conditions expected in notebook application. Performance results indicate that ultra-thin vapor chambers have very low spreading resistance and maximum heat transfer in can be up to 8W in steady state and 15W in transient. Ultra-thin VC in thickness lower than 0.5 mm can be a potential thermal solution in next generation of notebook computers.