Micro heat spreaders offer a promising solution as they have the potential to provide high effective thermal conductivities under high heat fluxes. Here, we report our new concept of experimental setup, which is imitated the heat spreader. Through our constructed experimental setup, we can estimate the performance of evaporator with condenser limit, and observe the liquid supply mechanism between condenser and evaporator. We use the nano-structured Cu micropost as evaporator. On condenser, we use the 3 different wettabilities surfaces. The wettabilities are prepared 3 different ways: super-hydrophilic (SHPi), hydrophobic (HPo), super-hydrophobic (SHPo). With changing the condenser’s wettabilites and gap size between evaporator and condenser, we can measure the performance evaporator and observe liquid transport from condenser to evaporator.