Polarization reversal in thin film lithium niobate on silicon
Rost, Timothy Alan
Rabson, Thomas A.
Master of Science thesis
The spontaneous polarization of thin film LiNbO$\sb3$ has been shown to be reversible with the application of an electric field at room temperature. This electric field is applied across the sample in the form of a voltage pulse, and polarization reversal is detected either as a photocurrent reversal, or as a current transient whose integrated area is proportional to the spontaneous polarization. For 80 mil$\sp2$ size areas of thickness.3 $\mu$m, the fastest switching speed was 500 ns. The samples consisted of a silicon substrate, a thin film of LiNbO$\sb3$ and a metal contact to form an MFS (metalferroelectric-semiconductor) structure. The LiNbO$\sb3$ film was formed by rf sputtering LiNbO$\sb3$ onto heated $\langle111\rangle$ silicon substrates.
Electronics; Electrical engineering; Condensed matter physics