disclosed is a thermo - buckled micro actuation unit made of parylene , which is a polymer having high thermal expansion coefficient , for delivering liquid from a source liquid section to a target liquid section , including a substrate on which a thermo - buckled micro actuation unit is formed . the thermo - buckled micro actuation unit includes upper and lower films made of polymers of high thermal expansion coefficient , a metal resistor arranged between the two films , and a flow channel defined between the lower film and the substrate . when electrical power is supplied to the metal resistor , the metal resistor generates heat and the heat is conducted to the upper and lower films , of which the thicknesses are different , whereby a temperature difference is induced therebetween and causing deformation of thermo - buckling , as a result of which the liquid is pumped from the source liquid section , through the flow channel , toward the target liquid section .