Band gap improvement in DRAM capacitors

摘要

A method for forming a DRAM MIM capacitor stack having low leakage current and low EOT involves the use of an compound high k dielectric material. The dielectric material further comprises a dopant. One component of the compound high k dielectric material is present in a concentration between about 30 atomic % and about 80 atomic % and more preferably between about 40 atomic % and about 60 atomic %. In some embodiments, the compound high k dielectric material comprises an alloy of TiO2 and ZrO2 and further comprises a dopant of Al2O3. In some embodiments, the compound high k dielectric material comprises an admixture of TiO2 and HfO2 and further comprises a dopant of Al2O3.

主权项

1. A method for forming a capacitor stack comprising:
forming a first electrode layer on a substrate,
the first electrode layer comprising MoO2; forming a compound high k dielectric material on the first electrode layer,
wherein the compound high k dielectric material is formed by admixing two or more high k dielectric material components,wherein one of the two or more high k dielectric material components comprises TiO2,wherein at least 30% of TiO2 is present in a rutile phase, andwherein a concentration of one of the components of the compound high k dielectric material is in the range between about 30 atomic % and about 80 atomic %; and forming a second electrode on the compound high k dielectric material.