This work investigates the flow boiling heat transfer in microchannels with the aim of developing compact cooling systems which can be adapted to miniaturized power components. Nano and micro-surface treatments were used as innovative techniques to improve the heat transfer performance as well as to delay the intermittent dryout. Initially,pool-boiling experiments were performed to highlight the impact of nanocoatings on nucleate-boiling mechanisms. It was observed that the surface wettability modified by nanoparticle deposition had significant effects on the boiling processes. Afterwards, a second experimental campaign was conducted to investigate the flow boiling in a microchannel with nanocoated and microstructured samples. These studies highlighted the impacts of surface wettability and of micro-patterning on two-phase flow patterns, pressure drop and heat transfer coefficient. In particular, significant enhancements in heat transfer coefficient and in intermittent dryout were obtained with micro structured samples.