ALD TaN from PDMAT in TSV architectures
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.