Precrystallization Engineering of Hf0.5Zr0.5O2 Film in Back-End-of-Line Compatible Ferroelectric Device for Enhanced Remnant Polarization and Endurance

High-performance ferroelectric devices compatible with the Back-End-of-Line (BEOL) process are necessary for their mass production and application. In this letter, pre-crystallization engineering of increasing the number of cycles of ZrO2 and HfO2 in each period of Hf0.5Zr0.5O2 (HZO) film growth process was utilized to improve the ferroelectric property of TiN/HZO/TiN capacitors at 400 degrees C annealing process. Grazing incidence X-ray diffraction shows that higher in-situ crystallized tetragonal phase nuclei can be formed in the HZO film with 3 cycles of ZrO2 and 3 cycles of HfO2 (3Z3H) in each period during the ALD step at 280 degrees C, which will enhance the formation of ferroelectric orthorhombic phase after rapid thermal annealing. The developed TiN/3Z3H/TiN capacitor shows high remnant polarization (2P(r)) of 45 mu C/cm(2), and better endurance of more than 10(10) cycles.