US 11,655,534 B2
Apparatus for reducing tungsten resistivity
Wenting Hou, San Jose, CA (US); Jianxin Lei, Fremont, CA (US); Jothilingam Ramalingam, Milpitas, CA (US); Prashanth Kothnur, San Jose, CA (US); and William R. Johanson, Gilroy, CA (US)
Assigned to APPLIED MATERIALS, INC., Santa Clara, CA (US)
Filed by APPLIED MATERIALS, INC., Santa Clara, CA (US)
Filed on Jul. 5, 2022, as Appl. No. 17/857,370.
Application 17/857,370 is a division of application No. 17/021,661, filed on Sep. 15, 2020, granted, now 11,447,857.
Prior Publication US 2022/0341025 A1, Oct. 27, 2022
Int. Cl. H01J 37/32 (2006.01); C23C 14/18 (2006.01); C23C 14/34 (2006.01); C23C 14/35 (2006.01); C23C 14/14 (2006.01); C23C 14/16 (2006.01)
CPC C23C 14/18 (2013.01) [C23C 14/14 (2013.01); C23C 14/16 (2013.01); C23C 14/3414 (2013.01); C23C 14/354 (2013.01); H01J 37/32027 (2013.01); H01J 37/32082 (2013.01)] 10 Claims
OG exemplary drawing
1. An apparatus for depositing tungsten film with low resistivity, comprising:
a physical vapor deposition (PVD) chamber with a processing volume disposed between a target and a substrate support, wherein the PVD chamber has a target-to-substrate spacing of approximately 75 mm to approximately 150 mm and wherein the target is made of tungsten and configured for sputtering by plasma generated in the processing volume;
a magnetron configured to generate magnetic fields during sputtering of the target;
a process gas supply source configured to provide krypton gas into the processing volume;
an RF power source configured to generate a plasma from the krypton gas within the processing volume at a frequency of approximately 40 MHz to approximately 75 MHz;
a bias power source configured to supply a bias to a substrate placed on the substrate support;
a magnetic field source surrounding the processing volume at a level proximate to a top surface of the substrate support, wherein the magnetic field source is configured to influence plasma density and distribution in the PVD chamber and uniformity of deposition on the substrate; and
a controller in communication with the apparatus and configured to generate a plasma in a pressure of approximately 1 mTorr to approximately 15 mTorr in a processing volume of the PVD chamber with a process gas of krypton and using RF power of approximately 6 kilowatts to 10 kilowatts with a frequency of approximately 60 MHz, to apply a bias power at a frequency of approximately 13.56 MHz to a substrate, and to sputter the target to deposit a tungsten thin film on the substrate, wherein at least approximately 90% of the tungsten thin film has a 110 crystal orientation plane approximately parallel to a top surface of the substrate, wherein the tungsten thin film has a resistivity value of approximately 9.5 μohm-cm or less at an approximately 200 angstrom thickness.