A method is provided for reducing the metal content and controlling the
metal depth profile of a gate dielectric layer in a gate stack. The
method includes providing a substrate in a process chamber, depositing a
gate dielectric layer on the substrate, where the gate dielectric layer
includes a metal element. The metal element is selectively etched from at
least a portion of the gate dielectric layer to form an etched gate
dielectric layer with reduced metal content, and a gate electrode layer
is formed on the etched gate dielectric layer.