Microfluidic valve unit for controlling flow of fluid and method of fabricating the same

A microfluidic valve unit for controlling the flow of fluid flowing along a channel, and a method of fabricating the same are provided. The valve unit includes a channel formed in a platform; a valve filler which includes a phase transition material that is disposed in the channel in a solid state at room temperature to close the channel and is melted when energy is applied thereto; and at least one capillary channel which extends from a sidewall of the channel and into which the valve filler flows when the valve filler is melted, wherein the at least one capillary channel has a cross-sectional area which is less than a cross-sectional area of the channel.