Method to form high k dielectric and silicide to reduce poly depletion by using a sacrificial metal between oxide and gate

摘要

A method of forming a gate comprising the following steps. A substrate is provided. A pre-gate structure is formed over the substrate. The pregate structure includes a sacrificial metal layer between an upper gate conductor layer and a lower gate dielectric layer. The pre-gate structure is annealed to form the gate. The gate comprising: an upper silicide layer formed from a portion of the sacrificial metal layer and a portion of the upper gate conductor layer from the anneal; and a lower metal oxide layer formed from a portion of the gate dielectric layer and a portion of the sacrificial metal layer from the anneal.