Diffusion-controlled oxygen depletion of semiconductor contact interface

摘要

A device is created by forming a layer of dielectric material on a silicon-containing region of a semiconductor substrate. An opening is created through the layer of dielectric material, the opening having a bottom and exposing the silicon-containing region. A metal stack is formed within the opening. The metal stack includes at least a first metal film on the silicon-containing region and a second gettering metal film on the first metal film. The metal stack is annealed to cause oxygen to migrate from the substrate to the gettering metal film. A first liner is formed within the opening. A fill metal is deposited in the opening.

主权项

1. A method of forming a contact, the method comprising:
forming a layer of dielectric material on a silicon-containing region of a semiconductor substrate; creating an opening through the layer of dielectric material, the opening having a bottom and exposing the silicon-containing region; forming a metal stack within the opening, the metal stack including at least a first metal film on the silicon-containing region and a second metal film on the first metal film; annealing the metal stack to cause oxygen to migrate from the substrate to the second metal film by using a forming gas anneal that is performed:
in an atmosphere at least partially composed of nitrogen gas and hydrogen gas;at a temperature of at least 350° C.; andfor at least 30 minutes; forming a first liner within the opening; and depositing a fill metal in the opening.