Atomic Layer Epitaxy Growth of BaS and BaS:Ce Thin Films from In Situ Synthesized Ba(thd)2

Saanila, Ville; Ihanus, Jarkko; Ritala, Mikko; Leskelä, Markku

doi:10.1002/(sici)1521-3862(199812)04:06<227::aid-cvde227>3.3.co;2-e

Cited by 25 publications

(8 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast, increasing GPCs with temperature were reported for some β-diketonate precursors, including Ba(thd) 2 (thd = 2,2,6,6-tetramethyl-3,5heptanedionate). 28 Temperature-independent growth with H 2 S has also been observed in some studies, including with Li(O t Bu) 19 and Sn( i PrAMD) 2 ( i PrAMD = N,N′-diisopropylacetamidinato). 29 The growth temperature can also affect the film roughness, crystallinity, and composition.…”

Section: ■ Previous Workmentioning

confidence: 53%

“…This has been observed in all of the ALD processes using alkyls and H 2 S. − Similar trends have been observed in several other ALD processes with H 2 S and are commonly attributed to a decrease in surface functional group coverage with increasing temperature. In contrast, increasing GPCs with temperature were reported for some β-diketonate precursors, including Ba(thd) 2 (thd = 2,2,6,6-tetramethyl-3,5-heptanedionate) . Temperature-independent growth with H 2 S has also been observed in some studies, including with Li(O t Bu) and Sn( i PrAMD) 2 ( i PrAMD = N , N ′-diisopropylacetamidinato) …”

Section: Previous Workmentioning

confidence: 94%

See 1 more Smart Citation

Atomic Layer Deposition of Metal Sulfide Materials

et al. 2015

View full text Add to dashboard Cite

CONSPECTUS: The field of nanoscience is delivering increasingly intricate yet elegant geometric structures incorporating an ever-expanding palette of materials. Atomic layer deposition (ALD) is a powerful driver of this field, providing exceptionally conformal coatings spanning the periodic table and atomic-scale precision independent of substrate geometry. This versatility is intrinsic to ALD and results from sequential and self-limiting surface reactions. This characteristic facilitates digital synthesis, in which the film grows linearly with the number of reaction cycles. While the majority of ALD processes identified to date produce metal oxides, novel applications in areas such as energy storage, catalysis, and nanophotonics are motivating interest in sulfide materials. Recent progress in ALD of sulfides has expanded the diversity of accessible materials as well as a more complete understanding of the unique chalcogenide surface chemistry. ALD of sulfide materials typically uses metalorganic precursors and hydrogen sulfide (H2S). As in oxide ALD, the precursor chemistry is critical to controlling both the film growth and properties including roughness, crystallinity, and impurity levels. By modification of the precursor sequence, multicomponent sulfides have been deposited, although challenges remain because of the higher propensity for cation exchange reactions, greater diffusion rates, and unintentional annealing of this more labile class of materials. A deeper understanding of these surface chemical reactions has been achieved through a combination of in situ studies and quantum-chemical calculations. As this understanding matures, so does our ability to deterministically tailor film properties to new applications and more sophisticated devices. This Account highlights the attributes of ALD chemistry that are unique to metal sulfides and surveys recent applications of these materials in photovoltaics, energy storage, and photonics. Within each application space, the benefits and challenges of novel ALD processes are emphasized and common trends are summarized. We conclude with a perspective on potential future directions for metal chalcogenide ALD as well as untapped opportunities. Finally, we consider challenges that must be addressed prior to implementing ALD metal sulfides into future device architectures.

show abstract

Section: ■ Previous Workmentioning

confidence: 53%

Section: Previous Workmentioning

confidence: 94%

Atomic Layer Deposition of Metal Sulfide Materials

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Similar in-situ strategies have already been found useful in overcoming drawbacks due to oligomerization of b-diketonate precursors. [18,19] In this paper we report on an in-situ strategy to synthesize the anhydrous La(hfac) 3 precursor for the MOCVD of LaF 3 . A closely related precursor is usually obtained in the hydrate form due to the tendency of the La 3+ ion to expand its coordination array beyond six.…”

Section: Introductionmentioning

confidence: 99%

In-situ Synthesis of the Anhydrous La(hfac)3 Precursor: A Viable Route to the MOCVD of LaF3

Condorelli

Gennaro

Fragalá³

2001

Chem. Vap. Deposition

View full text Add to dashboard Cite

The anhydrous La(hfac) 3 precursor was obtained in situ by a vapor±solid reaction between hexafluoroacetylactonate (Hhfac) and La 2 O 3 powder in the source reservoir of a metal±organic chemical vapor deposition (MOCVD) reactor. Fourier transform infrared spectroscopy (FTIR) in-situ measurements were used to identify the nature of the precursor in the gas phase. Clean LaF 3 films (60±260 nm thick) were deposited on SiO 2 /Si substrates in both Ar and Ar/O 2 environments. They were characterized by grazing incidence X-ray diffraction, (GIXRD), X-ray photoelectron spectroscopy (XPS) depth profiles, scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis. Very thin (<15 nm) films were also deposited in order to investigate the nucleation and growth processes. Deposited films were found to consist of islands grown on the silicon substrate. The surface coverage depends on the sublimation and substrate temperatures, as well as on the nature of the carrier/reacting gas.

show abstract

“…BaS:Ce thin films have been deposited by ALD using Ce(thd) 4 and in situ-synthesized Ba(thd) 2 as the Ce and Ba sources, respectively. 29 However, 1 kHz measurement frequency was needed in the previous study to achieve a visible emission (8 cd/m 2 ), and in that sense the Cp-based process of this study resulted in a clear enhancement to the emission brightness. No previous ALD studies on Eu-or Mn-doped BaS are known.…”

Section: Resultsmentioning

confidence: 79%

Electroluminescent SrS and BaS Thin Films Deposited by ALD Using Cyclopentadienyl Precursors

Ihanus

Hänninen

Hatanpää

et al. 2004

J. Electrochem. Soc.

Self Cite

View full text Add to dashboard Cite

Electroluminescent ͑EL͒ SrS and BaS thin films were deposited by the atomic layer deposition ͑ALD͒ technique using cyclopentadienyl-based metal precursors. The films were doped either with Cu, Ce, Pb, Mn, or Eu. BaS:Mn and BaS:Eu thin films were deposited for the first time by the ALD. The usable range of deposition temperatures was wide, but results of this and earlier ALD studies indicate that high deposition temperature is needed for the high emission intensity. It is shown that emission intensities and colors of the EL devices are comparable with the earlier ALD and chemical vapor deposition studies. It is also suggested that the dopant precursors have stronger impact to the emission than the host metal precursors, and that the use of the cyclopentadienyl-based dopants may result in further improvements in the performance of EL devices. The double-peak nature of Mn emission is also reported in both SrS and BaS, which is suggested to originate from Mn 2ϩ at different crystal sites.

show abstract

Atomic Layer Epitaxy Growth of BaS and BaS:Ce Thin Films from In Situ Synthesized Ba(thd)2

Cited by 25 publications

References 26 publications

Atomic Layer Deposition of Metal Sulfide Materials

Atomic Layer Deposition of Metal Sulfide Materials

In-situ Synthesis of the Anhydrous La(hfac)3 Precursor: A Viable Route to the MOCVD of LaF3

Electroluminescent SrS and BaS Thin Films Deposited by ALD Using Cyclopentadienyl Precursors

Contact Info

Product

Resources

About