Characterization of group II hafnates and zirconates for metal–insulator–metal capacitors

Thin layers of SrHfO3, BaHfO3 and BaZrO3 are deposited onto TiN substrates and investigated in view of memory capacitor applications. The as deposited layers are amorphous and show dielectric constants of about 20. Rapid thermal annealing induces crystallization in the cubic perovskite phase and results in an increase of the dielectric constant up to 45. A combination of X-ray absorption spectroscopy (XAS) and photoemission spectroscopy measurements reports high electronic band gap values comparable with that of reference HfO2 layers.