Forming nanotwinned regions in a ceramic coating at a tunable volume fraction

A method of manufacturing a ceramic thin film on a surface of a substrate in an evacuated chamber, the ceramic thin film comprising crystalline grains, wherein each of the crystalline grains comprises one or more nanotwinned regions with a volume fraction in a range of 30-80% of the ceramic thin film, the ceramic thin film comprises titanium, nitrogen, and boron, and a boron concentration of the ceramic thin film is in a range of 2-18 atomic percent, the method comprising:

• providing a plurality of targets comprising a plurality of sputtering materials, wherein the plurality of targets comprises a first target and a second target, the first target comprising titanium metal and the second target comprising titanium boride;
• forming a gas atmosphere in the evacuated chamber, wherein the atmosphere comprises nitrogen;
• and
• supplying electric power to the plurality of targets to cause co-sputtering of the plurality of sputtering materials to form the ceramic thin film comprising the one or more nanotwinned regions.