Method for providing a gate metal layer of a transistor device and associated transistor

摘要

A method includes providing a dummy gate structure on a substrate. The dummy gate structure includes a gate dielectric layer and a dummy gate electrode layer, and is laterally defined by inner sidewalls of a set of spacers. The method also includes laterally embedding the dummy gate structure, removing the dummy gate electrode, and providing a final gate electrode layer in between the inner sidewalls of the set of spacers. Providing the final gate electrode layer further includes providing a diffusion layer that extends on top of the gate dielectric layer, on inner sidewalls of the spacers, and on a portion of a front surface of embedding layers for the dummy gate structure. Providing the final gate electrode also includes providing a metal on top of the diffusion layer, applying an anneal step, and filling the area in between the inner sidewalls of the set of spacers with a final gate metal filling layer. The present disclosure also relates to an associated transistor.

主权项

1. A method for manufacturing a field effect transistor, the method comprising the steps of:
providing a dummy gate structure on a substrate, the dummy gate structure comprising a gate dielectric layer, the dummy gate structure being laterally defined by a gate trench defined by inner sidewalls of a set of spacers; laterally embedding the dummy gate structure by one or more embedding layers, the one or more embedding layers defining a front surface; and providing a final gate electrode layer in between the inner sidewalls of the set of spacers; and wherein providing the final gate electrode layer further comprises:
providing a diffusion layer, the diffusion layer extending at least on top of the gate dielectric layer, on inner sidewalls of the set of spacers, and on at least a portion of the front surface;providing a metal layer including a metal on top of a portion of the diffusion layer that is disposed over the front surface, and whereby the metal does not enter the gate trench;applying an anneal step, the anneal step being adapted for driving diffusion of the metal of the metal layer into the diffusion layer, and for further diffusing the metal in the diffusion layer towards the portion of the diffusion layer in the area corresponding to the area of the gate dielectric; andfilling the area in between the inner sidewalls of the set of spacers with a final gate metal filling layer.