Low-Temperature Chemical Vapor Depostion of Ruthenium and Manganese Nitride Thin Films

Abstract

Manganese nitride films were grown by chemical vapor deposition from the volatile manganese(II) amido precursor bis[di(tert)-butyl)amido]manganese(II)and ammonia. Between 80 and 200°C, the films grown from bis[di(tert )-butyl)amido]manganese(II)contain crystalline eta-Mn3N 2. At 300°C, a mixture of eta- and xi-phase manganese nitride with a manganese carbide impurity is deposited. Oxygen and carbon contamination in the bulk of the films is less than 1 atomic percent. Remarkably, the films are nearly completely crystalline at growth temperatures of 200°C and above. The growth rate of 5.9 nm/min at 200°C is also remarkably high for such a low growth temperature. The crystallinity and rapid growth rates are attributed to the labile metal-ligand bonding characteristic of high-spin MnII. As a result, reactive surface species remain mobile on the surface throughout much of the reaction pathway leading to nitride growth, and can settle into low-energy ordered arrangements before they become incorporated into the bulk by subsequent deposition activity.