Electrical Properties of PZT/Mg₂TiO₄ Thin Films Made by Low Pressure MOCVD

Abstract

Pb(Zr_xTi_{1 - x})O₃(PZT) thin films were deposited on Si substrates using Mg₂TiO₄ as the buffer layer and the electrical properties of those MFIS structures were investigated. PZT and Mg₂TiO₄ films were made by Low Pressure MOCVD technique. Perovskite PZT films have been successfully made at the substrate temperature of 600°C only when using Mg₂TiO₄ buffer layer. The crystallographic properties of PZT films were affected by the structure of the Mg₂TiO₄ films on which they grow. (100)-oriented PZT films were deposited on (100) Mg₂TiO₄ independently of deposition conditions. FE-SEM revealed that there is no remarkarble interdiffusion and no formation of reaction layer between PZT and Mg₂TiO₄ and/or between Mg₂TiO₄ and Si substrate. The capacitance-voltage (C-V) curves of the MFIS structure which were made with PZT and Mg₂TiO₄ buffer layer have shown the hysteresis resulted from the ferroelectric switching of the PZT films and the memory window was about 2V under programming voltage of ± 5V.

Keywords:

• PZT film
• Mg₂TiO₄
• MFIS
• Low Pressure MOCVD
• memory window