A micro-channel heat sink with integrated temperature sensors for phase transition study

A unique technique of maskless and self-aligned Si etch between bonded wafers was developed and applied to fabricate a micro-channel heat sink integrated with a heater and an array of temperature sensors. The technique allowed the formation of self-aligned and self-stopped etching of grooves between the bonded wafers. The device, consisting of distributed sensors, allowed direct temperature measurements to evaluate local heat transfer rates under forced convection boiling conditions. Temperature distributions along the heat sink were measured for different levels of power dissipation. The onset of critical heat flux condition was investigated as a function of channel size and liquid flow rate. The results suggest that the bubble dynamic mechanism in micro-channels maybe different from that with conventional channels.