Si:SrTiO3-Al2O3-Si:SrTiO3 multi-dielectric architecture for metal-insulator-metal capacitor applications

Abstract

Metal-insulator-metal (MIM) capacitors comprised of amorphous Si:SrTiO3-Al2O3-Si:SrTiO3 multi-dielectric architecture have been fabricated employing a combination of pulsed laser and atomic layer deposition techniques. The voltage linearity, temperature coefficients of capacitance, dielectric and electrical properties upon thickness were studied under a wide range of temperature (200 – 400 K) and electric field stress (± 1.5 MV/cm). A high capacitance density of 31 fF/µm2, a low voltage coefficient of capacitance of 363 ppm/V2, a low temperature coefficient of capacitance of < 644 ppm/K and an effective dielectric constant of ~133 are demonstrated in a MIM capacitor with ~1.4 nm capacitance equivalent thickness in a ~40 nm thick ultra high-k multi-dielectric stack. All of these properties make this dielectric architecture of interest for next generation highly scaled MIM capacitor applications.