A memory cell includes a selection transistor on a substrate and an antifuse on the substrate. The selection transistor includes a first gate connected to a read word line, a first gate insulation layer that insulates the first gate from the substrate, a first source region connected to a bit line, and a first drain region, an impurity concentration of the first drain region being lower than an impurity concentration of the first source region. The antifuse includes a first electrode connected to a program word line and a second electrode connected to the selection transistor.