Abstract
A Ge-stabilized tetragonal ZrO 2 dielectric with a permittivity (κ) value of 36.5 has been obtained by annealing a ZrO 2 /Ge/ ZrO 2 laminate at 500 °C and it is a more reliable approach toward stabilizing a tetragonal ZrO 2 film. However, metal-insulator-metal (MIM) capacitors with the sole tetragonal ZrO 2 film as an insulator achieve a high capacitance density of 27.8 fF/μ m 2 at the price of a degraded quadratic voltage coefficient of capacitance (VCC) of 81 129 ppm/ V 2 and unacceptably high leakage current. By capping an amorphous La-doped ZrO 2 layer with a κ value of 26.3 to block grain boundaries-induced leakage paths of the crystalline ZrO 2 dielectric, high-performance MIM capacitors in terms of a capacitance density of 19.8 fF/μ m 2 , a VCC of 3135 ppm/ V 2 , leakage current of 6.5× 10-8 A/ cm 2 at -1 V, as well as a satisfactory capacitance change of 1.21% after ten-year operation can be realized. © 2011 American Institute of Physics.