Patent attributes
Method for forming tungsten gap fill on a structure, including high aspect ratio structures includes depositing a tungsten liner in the structure using a physical vapor deposition (PVD) process with high ionization and an ambient gas of argon or krypton. The PVD process is performed at a temperature of approximately 20 degrees Celsius to approximately 300 degrees Celsius. The method further includes treating the structure with a nitridation process and depositing bulk fill tungsten into the structure using a chemical vapor deposition (CVD) process to form a seam suppressed boron free tungsten fill. The CVD process is performed at a temperature of approximately 300 degrees Celsius to approximately 500 degrees Celsius and at a pressure of approximately 5 Torr to approximately 300 Torr.
