Properties of titanium nitride thin films deposited by rapid-thermal-low-pressure-metalorganic-chemical-vapor-deposition technique using tetrakis (dimethylamido) titanium precursor

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Abstract
Titanium nitride (TiNx) thin films were deposited onto InP by means of the rapid‐thermal‐low‐pressure‐chemical‐vapor‐deposition (RT‐LPMOCVD) technique, using the tetrakis (dimethylamido) titanium (Ti(NMe2)4 or DMATi) complex as the precursor. Depositions were successfully carried out at temperatures below 550 °C, pressure range of 5–20 Torr and duration of 50 to 90 s, to give layer thicknesses up to 200 nm and growth rates in the range of 0.8 to 4.5 nm/s. These films had a stoichiometric structure and contained nitrogen and titanium in a ratio close to unity, but also contained a significant amount of carbon and oxygen. The elements were spread uniformly through the films, the nitrogen was Ti bounded, and the carbon was partially titanium bonded and organic bonded as well. The film resistivity was in the range of 400–800 μΩ cm−2; the stress was always compressive, in the range of − 0.5 × 109 to − 2 × 1010 dyne cm−2, and the film had a good morphology. These layers performed as an ohmic contact while deposited onto p‐In0.53Ga0.47As material, (Zn‐doped 1.2 × 1018 cm−3), provided an excellent step coverage for high aspect ratio via holes and were deposited selectively onto the InP and based materials when using SiO2 mask. This represents the first report of TiNx films deposited in a commercial RT‐LPMOCVD reactor using the DMATi precursor.