New Mechanisms for Ozone-Based ALD Growth of High-k Dielectrics via Nitrogen-Oxygen Species

Abstract

Optimization of the O 2 /N 2 feed gas flow during O 3 generation by dielectric barrier discharge was found to improve the growth rate and uniformity of HfO 2 and La 2 O 3 films by atomic layer deposition (ALD) in a hot wall cross-flow thermal ALD reactor. Discharge products from the O 3 generator and from the exhaust of the ALD reactor were analyzed by FTIR spectrometry. N 2 O, N 2 O 5 , NO 2 and NO species were detected, as well as unreacted O 3 . Alternate models which could explain the behavior of various ozone-based ALD processes utilizing N 2 doped O 3 generation are presented.

TiO2 thin film patterns prepared by chemical vapor deposition and atomic layer deposition using an atmospheric pressure microplasma printer

“…At low temperatures (<100°C), the GPC of TTIP/O 3 process was reported to be 0.01 nm, and hence we can infer that the role of O 3 during ALD with the microplasma printer at 60°C is negligible. Nitrogen oxides such as NO 2 and NO 3 have been reported to have impact on the growth of different metal oxides during O 3 ‐based ALD when O 3 is generated by DBD; addition of N 2 to the O 2 supply of the DBD (as O 3 generator for ALD) and generation of N x O y species has shown to yield a higher GPC in HfO 2 , ZrO 2 , La 2 O 3 , and a lower GPC in Al 2 O 3 , O 3 ‐based ALD processes . To our knowledge, nitrogen oxides have not been explored as oxidants in ALD of TiO 2 and hence their impact on the ALD growth of TiO 2 is not known.…”

Atomic layer deposition of tantalum oxide and tantalum silicate from TaCl5, SiCl4, and O3: growth behaviour and film characteristics

“…The N 2 /O 2 ratio used for O 3 generation has been reported to inuence the growth characteristics of several ALD processes, in particular the ALD of HfO 2 from HfCl 4 and O 3 . [19][20][21] We have therefore also investigated the effect of the N 2 /O 2 ratio on the Ta 2 O 5 and TaSiO x processes. This is shown in Fig.…”

“…Thus far, only few reports are available on the ALD of Ta 2 O 5 and TaSiO x from halides and O 3 . [19][20][21] As far as O 3 -based Ta 2 O 5 ALD processes are concerned, there have been limited reports on the ALD of Ta 2 O 5 from Ta(C 2 H 5 O) 4 (C 4 H 10 NO), t BuN ¼ Ta(NEt 2 ) 3 , and the pyrazolate Ta(N t Bu)( t Bu 2 pz) 3 precursors. [22][23][24] The growth per cycle (GPC) of Ta 2 O 5 from those precursors was found to be rather low.…”

Infrared and Optical Emission Spectroscopy Study of the Surface Chemistry in Atmospheric-Pressure Plasma-Enhanced Spatial ALD of Al2O3

“…23 Jung et al used infrared spectroscopy to monitor the O3 content at the inlet and outlet of their ALD reactor. 24 Finally, Zoubian et al analyzed the exhaust gas from their spatial reactor by FTIR spectroscopy and micro-gaschromatography. 25 Figure 1 shows a schematic of the diagnostics assembled on the PE-s-ALD reactor which was described in more detail elsewhere.…”