A special reactor coupled to a high-temperature mass spectrometer was specifically designed for the study of vaporization and thermal cracking of organometallic precursors. This reactor has two kinds of settings. One is a single Knudsen effusion cell which enables the analysis of the composition of saturated vapors and the determination of the partial pressure of each gaseous molecule in equilibrium with its condensed phase. This cell is an evaporation/sublimation cell (operating from 243 to 473 K), which can be tightly closed--like a vacuum chamber--in order to protect organometallic compounds against moisture and atmospheric components. This cell can be independently weighed usefully to evaluate the equilibrium vapor pressures of the sample using the mass-loss method. During experiments, the effusion aperture is externally opened for direct mass spectrometric measurements. The other setting dedicated to the study of thermal decomposition of gaseous molecules consists of a set of tandem cells: the previously described Knudsen cell and a cracking cell (operating from 293 to 973 K).

In this study, we report the TaN ALD film growth from PDMAT, in Through-Silicon Vias with NH3 as nitrogen precursor and H2 as reducing agent. We report deposits on planar and patterned substrates with high aspect ratios (5 to 20). As a reference, TaN was deposited from PDMAT and NH3 only, and the influence of H2 injections as reducing agent is reported. H2 was introduced in two manners: either during the PDMAT pulse or during the NH3 pulse. The samples obtained when H2 is introduced during the PDMAT pulse show a lower amount of oxygen than the reference deposited with only PDMAT and NH3 as precursors. Unexpectedly, when H2 is introduced during the NH3 pulse, the oxygen content increases compared to the reference. An experimental study of the deposition parameters was carried out by in situ microgravimetry to explain the H2 influence on the TaN deposition.