Germanium antimony telluride materials are described, e.g., material of the formula GexSbyTezCmNn, wherein x is about 0.1-0.6, y is about 0-0.7, z is about 0.2-0.9, m is about 0.02-0.20, and n is about 0.2-0.20. One specific composition includes from 0 to 50% Sb, from 50 to 80% Te, from 20 to 50% Ge, from 3 to 20% N and from 2 to 15% carbon, wherein all atomic percentages of all components of the film total to 100 atomic %. Another specific composition includes from 10 to 50% Sb, from 50 to 80% Te, from 10 to 50% Ge, from 3 to 20% N and from 3 to 20% carbon, and wherein all atomic percentages of all components of the film total to 100 atomic %. Material of such composition is useful to form phase change films, e.g., as conformally coated on a phase change memory device substrate to fabricate a phase change random access memory cell.