Titanium nitride ͑TiN͒ films were deposited using plasma-enhanced atomic layer deposition ͑PEALD͒ from the organometallic precursor tetrakis-dimethyl-amino-titanium ͑TDMAT͒ with hydrogen ͑H 2 ͒ as a coreactant. Low-resistivity values lying from 210 to 275 ⍀ cm were achieved for 10 nm thick films deposited at low temperature: 150°C. The effects of temperature, plasma time, and plasma power were investigated. It was demonstrated that the chemical reaction is complementary and self-limiting. A minimum energy is necessary to reach the low-resistivity plateau. Chemical and physical properties of the films are also reported and a surface reaction mechanism is proposed. It is suggested that after TDMAT chemisorption to the surface, amines are removed by hydrogen radicals, and at the same time, titanium carbide bonds ͑Ti-C͒ are formed. The low resistivity results from the presence of Ti 2 C or Ti 2 N phases in the PEALD TiN film. The industrial viability of this process was also evaluated on 300 mm wafers. Good performances were obtained on wafer-to-wafer uniformity and step coverage, while some improvements related to the within-wafer uniformity are required.TiN is one of the most widely used metals for electrodes of metal/insulator/metal ͑MIM͒ capacitors because its barrier height and chemical stability with most of the dielectrics generally provide low leakage current and good voltage linearity for capacitors, 1,2 and also because it is easy to etch and to polish compared to other metals for electrodes such as TaN, WN͑C͒, Ru... . In the case of threedimensional ͑3D͒ capacitors with high-aspect-ratio features ͑to increase capacitance density͒, metal electrodes should be very conformal with low resistivity for device operation in high frequencies.While chemical vapor deposition ͑CVD͒ TiN is faced with some limitations related to poor conformality, atomic layer deposition ͑ALD͒ offers the outstanding advantage of thickness uniformity, even on the sidewalls of 3D capacitors, thanks to its two main characteristics of complementary and self-limiting surface reactions. 3 The aim of the study was to develop a low-temperature process for the deposition of low-resistivity TiN films, with the lowest defectivity. In this article, defectivity refers to the presence of solidphase particles embedded in the deposited film, or on top of it, generated in gas phase or coming from some peeled-off films deposited inside the reactor and carried by the reactant gas flows.The motivations of lowering the TiN deposition temperature are the integration of the electrode material for MIM capacitors and the investigation of the ALD process. The capacitor electrodes are embedded in the upper part ͑"back-end of line"͒ of integrated circuits, i.e., within the stack of insulators and interconnects. This environment can be very sensitive to high temperatures, especially when low-permittivity dielectrics ͑low-k͒ or some silicides like NiSi are used. From the ALD process point of view, lowering temperature minimizes decomposition of the organometallic pr...

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Plasma enhanced metal organic chemical vapor deposition (PEMOVCD) of titanium nitride with dual frequency plasma sources were studied by means of plasma and material characterization. Adding a low frequency to a radio frequency plasma in order to enhance the deposition reaction mechanism is demonstrated. An in depth investigation of plasma by optical emission spectroscopy shows that due to secondary electrons heating the plasma, it enters a gamma-mode and that LF permits better dissociation of the H 2 reactant gas. Moreover, it appears that the TiN metal organic precursor is not completely dissociated (no Ti * emission) but new species are observed that indicate a different fragmentation of the precursor. When LF plasma is used these modifications can be correlated to a change in the deposition reaction mechanism which affects the properties of the deposited material. Strong modifications of the TiN properties and deposition rate are observed when adding 17-60 W LF to a 200 W RF plasma. For example, with 35 W LF added to a 200 W RF, the deposition rate is increased by a factor two and the film appears to be less resistive (by 50%) and has a higher density. Such effects are not observed when only increasing the RF power (from 200 to 300 W with no LF power).

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