Characteristics of LiNbO3 memory capacitors fabricated using a low thermalbudget process

We investigated LiNbO3 metal Ferroelectric semiconductor (MFS) capacitors b ecause of the following advantages: a low interface trap density, a low int eraction with Si substrate, and a large remanent polarization. Ferroelectri c LiNbO3 thin films were grown directly on p-type Si(100) substrates for me tal ferroelectric semiconductor field effect transistor (MFSFET) applicatio ns. Low temperature film growth and post rapid thermal anneal (RTA) treatme nts improved the leakage current of films while keeping other properties al most the same as high substrate temperature grown samples. We reduced the l eakage current density of LiNbO3 films from 10(-5) A/cm(2) to 10(-7) A/cm(2 ) with RTA treatment. LiNbO3 MFS capacitors exhibited a breakdown electric field of greater than 500 kV/cm. RTA treatment above 600 degreesC converted LiNbO3 films from amorphous to polycrystalline states with (012), (015), ( 022), and (023) planes. The polycrystalline LiNbO3 MFS capacitors illustrat ed the ferroelectric switching characteristics with a memory window ranging from 0.6 to 1.9 V. We obtained a remanent polarization of 2.74 muC/cm(2) a nd a coercive field of 170 kV/cm using the LiNbO3 MFS capacitors. (C) 2001 Published by Elsevier Science Ltd.