Measurement of Performance Characterization of Ultra-Thin Vapor Chamber

The next generation of 5G mobile phone cooling requires many ultra-thin vapor chambers. This paper discusses how to measure the performance characterization of the vapor chamber. All the experiment is processing under the horizontal orientation so that the gravity effect could reduce to minimum. The thermal diffusivity of the two ultra-thin vapor chambers VC-A (180*80*1mm
³
) and VC-B (90*90*0.4mm
³
) developed from laboratory are α
_VC-A
=1.9(cm
²
/s) and α
_VC-B
=1.44(cm
²
/s). Converted to equivalent effective thermal conductivity are K
_A
=4833.3(W/m.K) and K
_B
=3069(W/m.K), which is about ten times of that of pure copper. The maximum heat transfer of VC-B is Q
_VC
max,B
=210(W), the axial thermal resistance R
_th,VC,Z,B
=0.04 (K/W), and the thermal resistance of vapor chamber R
_th,VC,B
=0.42 (K/W). Using the same method to test the thicker vapor chamber of C brand (90*90*3mm
³
), the Q
_VC,
max,C
^=551(W)
, the axial thermal resistance R
_th,VC,Z,C
=0.08 (K/W), and the average thermal resistance of the vapor chamber is R
_th,VC,C
=0.177(K/W). The highest thermal conductivity K value vapor chamber with 90×60×0.4 mm
³
designed in ACL currently is vapor chamber VC-D, the equivalent thermal conductivity is 33519 (W/m-k).