575
Following deposition , each layer was thermochemically converted to Cr3C2 at 950 °C in a gas atmosphere containing 76 vol. % Ar , 4 vol. % H2 , 20 % vol. % CH4 .
 concept or principle: deposition; process parameter: layer; concept or principle: gas; enabling technology: Ar
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
 Entities: deposition, layer, gas, Ar 
Answer:
 concept or principle: deposition; process parameter: layer; concept or principle: gas; enabling technology: Ar