The $LiNbO_3$ thin films were prepared directly on Si(100) substrates by conventional RF magnetron spurttering system for nonvolatile memory applications. RTA(Rapid Thermal Annealing) treatment was performed for as-deposited films in an oxygen atmosphere at 600 $^{circ}C$ for 60 s. The rapid thermal annealed films were changed to poly-crystalline ferroelectric nature from amorphous of as-deposition. The resistivity of the ferroelectric $LiNbO_3$ film was increased from a typical value of $1{sim}2{ imes}10^8{Omega}{cdot}cm$ before the annealing to about $1{ imes}10^{13}{Omega}{cdot}cm$ at 500 kV/cm and reduced the interface state density of the $LiNbO_3/Si$ (100) interface to about $1{ imes}10^{11}/cm^2{cdot}eV$. Ferroelectric hysteresis measurements using a Sawyer-Tower circuit yielded remanent polarization ($P_r$) and coercive field ($E_c$) values of about 1.2 ${mu}C/cm^2$ and 120 kV/cm, respectively.