A dielectric film containing HfO2/ZrO2 nanolaminates and
a method of fabricating such a dielectric film produce a reliable gate dielectric
having an equivalent oxide thickness thinner than attainable using SiO2.
A gate dielectric is formed by atomic layer deposition of HfO2 using
a HfI4 precursor followed by the formation of ZrO2 on the
HfO2 layer. The HfO2 layer thickness is controlled by repeating
for a number of cycles a sequence including pulsing the HfI4 precursor
into a reaction chamber, pulsing a purging gas into the reaction chamber, pulsing
a first oxygen containing precursor into the reaction chamber, and pulsing the
purging gas until the desired thickness is formed. These gate dielectrics containing
HfO2/ZrO2 nanolaminates are thermodynamically stable such
that the HfO2/ZrO2 nanolaminates will have minimal reactions
with a silicon substrate or other structures during processing.
