A conformal low resistivity fluorine free tungsten for FinFET metal gate and 3D memory applications

Tungsten has been the material of choice for contact and gate metallization, and continues to be used in FINFET architectures. In this work, we developed a low resistivity conformal Fluorine free tungsten film that can nucleate the WF6 based ALD/CVD W growth while blocking the fluorine diffusion from the bulk W fill material. It provides significant benefit in integration performance enhancement compare to common processes used for tungsten metallization.