Area Selective Deposition of Metals from the Electrical Resistivity of the Substrate

Nadhom, Hama; Boyd, Robert; Rouf, Polla; Lundin, Daniel; Pedersen, Henrik

doi:10.1021/acs.jpclett.1c00415

Cited by 7 publications

(3 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is necessary to explore inherently selective ALD as an important supplementary method, which relaxes process complexity. , Inherently selective ALD, which is free of inhibitors and removing steps, strongly relies on surface chemistry. , We have reported the inherently selective ALD of oxides on terrace and edge sites of metallic nanoparticles. The selectivity originates from intrinsic differences in binding energies of precursors on facets and low coordinated sites. − Adjusting the kinetic parameters, including temperature, precursor partial pressure, and selecting proper precursors, can extend the selective deposition window. − As for the selective ALD on different materials, various material combinations between metal, semiconductor or dielectrics are achieved, such as Ag and SiO 2 , Pt and SiO 2 , , α-Si:H and SiO 2 , − SiO 2 and SiN, , TiN and SiO 2 , , and so forth. These methods primarily rely on different surface functional groups, such as hydride versus hydroxyl and amino versus hydroxyl, and adjusting deposition temperature could also enlarge the differences of growth rate on these surfaces.…”

Section: Introductionmentioning

confidence: 99%

Surface Acidity-Induced Inherently Selective Atomic Layer Deposition of Tantalum Oxide on Dielectrics

Lan

Cao

et al. 2022

Chem. Mater.

View full text Add to dashboard Cite

Selective deposition shows a great perspective for the downscaling of nanoelectronics. In this work, inherently selective atomic layer deposition (ALD) of tantalum oxide was studied on a series of oxide substrates. The Ta2O5 films linearly grow on acidic oxides of MnO2, SiO2, and Ta2O5, while there are long nucleation delays on basic oxides such as Al2O3 and HfO2. The inherent selectivity is induced through acidity differences which influence the reaction path, and the H-transfer reaction is a key factor. The Ta(OEt)5 precursor with alkaline ligands tends to chemically adsorb on acidic SiO2 surfaces through H-transfer reaction between surface hydroxyls and precursor molecules. Through H-transfer reaction, the ligands of the Ta(OEt)5 precursor are dissociated into ethanol molecules and the remaining intermediates are strongly chemisorbed on the surface, initiating the following nucleation. However, it is hard to nucleate on basic Al2O3 and HfO2 substrates because the H-transfer reaction is blocked. Moreover, robust selectivity only exists within the ALD temperature window, which highlights that tuning deposition temperature is also an effective way to amplify selectivity. The obstruction of H-transfer reaction on basic oxides provides a new strategy for inherently selective ALD, which will expand the selective toolbox of nanofabrication for next-generation nanoelectronic applications.

show abstract

Section: Introductionmentioning

confidence: 99%

Surface Acidity-Induced Inherently Selective Atomic Layer Deposition of Tantalum Oxide on Dielectrics

Lan

Cao

et al. 2022

Chem. Mater.

View full text Add to dashboard Cite

show abstract

“…[28] SiO 2 (PE-ALD) [7,24,25] β-Ga 2 O 3 (PE-ALD) [38] Silicon nitride (PE-ALD) [22,23,27,31,37,40] Plasma treatment (PE-ALD) [26] Electron treatment (CVD based) [36,39] GaN (CVD based) [42,44,45,55] InN (CVD based) [41][42][43]45,47,48,53,57,58] InGaN (CVD based) [49,51,54,56] InN nanopillars (CVD based) [46,50,52,55] The oxygen contamination overview provided in this introduction is followed by an experimental examination of some effects related to the surface modification of cathode materials by the generated plasma. In particular, we examine changes that have been observed for aluminum and stainless-steel cathodes.…”

Section: Materials (And Process) Referencementioning

confidence: 99%

Recent Advances in Hollow Cathode Technology for Plasma-Enhanced ALD—Plasma Surface Modifications for Aluminum and Stainless-Steel Cathodes

Butcher

Georgiev²,

Georgieva³

2021

Coatings

View full text Add to dashboard Cite

Recent designs have allowed hollow cathode gas plasma sources to be adopted for use in plasma-enhanced atomic layer deposition with the benefit of lower oxygen contamination for non-oxide films (a brief review of this is provided). From a design perspective, the cathode metal is of particular interest since—for a given set of conditions—the metal work function should determine the density of electron emission that drives the hollow cathode effect. However, we found that relatively rapid surface modification of the metal cathodes in the first hour or more of operation has a stronger influence. Langmuir probe measurements and hollow cathode electrical characteristics were used to study nitrogen and oxygen plasma surface modification of aluminum and stainless-steel hollow cathodes. It was found that the nitridation and oxidation of these metal cathodes resulted in higher plasma densities, in some cases by more than an order of magnitude, and a wider range of pressure operation. Moreover, it was initially thought that the use of aluminum cathodes would not be practical for gas plasma applications, as aluminum is extremely soft and susceptible to sputtering; however, it was found that oxide and nitride modification of the surface could protect the cathodes from such problems, possibly making them viable.

show abstract

“…Also, the CVD method only functions on low-resistivity substrates, where the electron current from the plasma can be conducted away. 5 Although these results strongly suggest that the plasma electrons are active in the surface chemistry, more advanced in-situ measurements are needed to form a surface chemical model of the deposition chemistry in the new CVD method.…”

Section: Introductionmentioning

confidence: 99%

Biased quartz crystal microbalance method for studies of CVD surface chemistry induced by plasma electrons

Niiranen

Nadhom

Zanáška

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

In a recently presented chemical vapor deposition (CVD) method, plasma electrons are used as reducing agents for deposition of metals. The plasma electrons are attracted to the substrate surface by a positive substrate bias. Here, we present how a standard quartz crystal microbalance (QCM) system can be modified to allow applying a DC bias to the QCM sensor to attract plasma electrons to it and thereby also enable in situ growth monitoring during the electron-assisted CVD method. We show initial results from mass gain evolution over time during deposition of iron films using the biased QCM and how the biased QCM can be used for process development and provide insight to the surface chemistry by time-resolving the CVD method. Post deposition analyzes of the QCM crystals by cross-section electron microscopy and high-resolution X-ray photoelectron spectroscopy, show that the QCM crystals are coated by an iron-containing film and thus function as substrates in the CVD process. A comparison of the areal mass density given by the QCM crystal and the areal mass density from elastic recoil detection analysis and Rutherford backscattering spectrometry was done to verify the function of the QCM setup. Time-resolved CVD experiments show that this biased QCM method holds great promise as one of the tools for understanding the surface chemistry of the newly developed CVD method.

show abstract

Area Selective Deposition of Metals from the Electrical Resistivity of the Substrate

Cited by 7 publications

References 19 publications

Surface Acidity-Induced Inherently Selective Atomic Layer Deposition of Tantalum Oxide on Dielectrics

Surface Acidity-Induced Inherently Selective Atomic Layer Deposition of Tantalum Oxide on Dielectrics

Recent Advances in Hollow Cathode Technology for Plasma-Enhanced ALD—Plasma Surface Modifications for Aluminum and Stainless-Steel Cathodes

Biased quartz crystal microbalance method for studies of CVD surface chemistry induced by plasma electrons

Contact Info

Product

Resources

About