Reactively sputtered titanium nitride films for submicron contact barrier metallization

Sun

Journal of Applied Physics

et al. 1996

173

Study on the interfaces of Cu/PAN and PAN/Si by secondary ion mass spectroscopy and scanning electron microscopy J. Efficiency of TiN diffusion barrier between Al and Si prepared by reactive evaporation and rapid thermal annealingThis work investigated the barrier properties of metalorganic chemical-vapor-deposited ͑CVD͒ tantalum nitride ͑TaN͒ and physical-vapor-deposited ͑PVD͒ TaN between Cu and Si. The CVD TaN film had a preferred orientation ͑200͒ with a grain size of around 60 nm, while the PVD TaN had a ͑111͒ preferred orientation with a grain size of around 20 nm, as determined by transmission electron microscopy ͑TEM͒ and x-ray diffraction ͑XRD͒ analyses. Degradation study of the Cu/ TaN/Si contact system was also performed by sheet resistance measurement, scanning electron microscopy ͑SEM͒, XRD, secondary ion mass spectroscopy ͑SIMS͒, and shallow junction diodes. These results indicated that the PVD TaN film can act as a better diffusion barrier than the CVD TaN film. The higher thermal stability of PVD TaN than CVD TaN can be accounted by their difference in microstructures. The failure mechanisms of both CVD TaN and PVD TaN films as diffusion barriers between Cu and Si were also discussed.

Section: Resultsmentioning

confidence: 99%

Comparison of the diffusion barrier properties of chemical-vapor-deposited TaN and sputtered TaN between Cu and Si

Sun

Journal of Applied Physics

et al. 1996

173

“…6,8,28 Oxygen was incorporated into the sample during growth, and also after deposition for those films that were porous (see Sec. Generally associated with increasing film resistivities, oxygen also plays a key role in the barrier properties of TiN.…”

Section: B Stoichiometrymentioning

confidence: 99%

Atmospheric pressure chemical vapor deposition of TiN from tetrakis(dimethylamido)titanium and ammonia

Musher

Gordon

1996

J. Mater. Res.

Near stoichiometric titanium nitride (TiN) was deposited from tetrakis(dimethylamido)titanium (TDMAT) and ammonia using atmospheric pressure chemical vapor deposition. Experiments were conducted in a belt furnace; static experiments provided kinetic data and continuous operation uniformly coated 150-mm substrates. Growth rate, stoichiometry, and resistivity are examined as functions of deposition temperature (190-420 ± C), ammonia flow relative to TDMAT (0-30), and total gas-flow rate (residence time 0.3 -0.6 s). Films were characterized by sheet resistance measurements, Rutherford Backscattering Spectrometry, and X-Ray Photoelectron Spectrometry. Films deposited without ammonia were substoichiometric (N͞Ti , 0.6 -0.75), contained high levels of carbon (C͞Ti 0.25-0.40) and oxygen (O͞Ti 0.6 -0.9), and grew slowly. Small amounts of ammonia (NH 3 ͞TDMAT > 1) brought impurity levels down to C͞Ti , 0.1 and O͞Ti 0.3 -0.5. Ammonia increased the growth rates by a factor of 4-12 at temperatures below 400 ± C. Films 500Å thick had resistivities as low as 1600 mV-cm when deposited at 280 ± C and 1500 mV-cm when deposited at 370 ± C. Scanning electron micrographs indicate a smooth surface and poor step coverage for films deposited with high ammonia concentrations.

“…Starting from the poly Si/thermal oxide/Si substrate, a-Si and a-Si/TiN interlayers were deposited prior to the reactive CVD of CoSi 2 . The substrates were prepared by the thermal oxidation of n-type (100)Si wafers, followed by the deposition of 200 nm poly-Si by low-pressure chemical vapor deposition (LPCVD) at 590 C. A 30-nm-thick TiN interlayer was deposited by reactive magnetron sputtering at 200 C. After this TiN deposition, one of the samples was annealed at 600 C for 2 min in N 2 ambient to observe the nitrogen stuffing effect 16) on the thermal stability. A 40-nmthick a-Si interlayer was deposited on the TiN interlayer and poly-Si substrate by plasma-enhanced chemical vapor deposition (PECVD) at 400 C. A 250-nm-thick a-Si/thermal oxide substrate was prepared to compare the reactively CVD CoSi 2 on poly-Si with that on a-Si.…”

Section: Methodsmentioning

confidence: 99%

Improvement in Thermal Stability of Chemical Vapor Deposition CoSi₂/Polycrystalline Silicon Using TiN and Amorphous Silicon Interlayers

Hong

Kim

Lee

et al. 2006

jjap

The effect of TiN and amorphous silicon (a-Si) interlayers on the thermal stability of a blanket CoSi2 polycrystalline silicon (poly-Si) gate electrode structure has been investigated. CoSi2 was formed by reactive chemical vapor deposition (CVD) using a Co(η5-C5H5)(CO)2 precursor at 650°C. The TiN interlayer effectively suppressed the interdiffusion of the Co and Si atoms between CoSi2 and poly-Si, thus the thermal stability of the structure was improved significantly up to 1000°C. The a-Si interlayer also improved the thermal stability of CoSi2, even though such an improvement is not as great as the effect of the TiN interlayer. We found that the interfacial native oxide between CoSi2 and poly-Si had the same effect as the TiN interlayer in suppressing the interdiffusion of Co and Si atoms.