Improved Capacitance Density and Reliability of High-k Ni/ZrO2/TiN MIM Capacitors Using Laser-Annealing Technique

Abstract

We have fabricated high-k Ni/ZrO2/TiN metal-insulator-metal capacitors with a very high 52-fF/mu m(2) capacitance density, a low leakage current of 1.6 x 10(-7) A/cm(2), and good ten-year reliability with a small Delta C/C of 1.7% at 2 V. From X-ray diffraction measurements, laser annealing can improve the permittivity of ZrO2 due to tetragonal-phase formation which in turn helps enhance capacitance density and reliability. Such excellent device integrity is attributed to the combination of enhanced ZrO2 tetragonal phase by laser annealing, high work-function Ni electrode, and good bottom-interface treatment.