Diffusion barrier properties of transition metal thin films grown by plasma-enhanced atomic-layer deposition

AbstractTa films were grown by plasma-enhanced atomic layer deposition (PE-ALD) at temperatures from room temperature up to 300 °C using TaCl5 as source gas and RF plasma-produced atomic H as the reducing agent. Post-deposition ex situ chemical analyses showed that the main impurity is oxygen, incorporated during the air exposure prior to analysis with typically low Cl concentration below 1 at %. The X-ray diffraction indicates that ALD Ta films are amorphous or composed of nano-grains. The typical resistivity of ALD Ta films was 150-180 μΩ cm, which corresponds to that of β-Ta phase, at a wide range of growth parameters. The conformality of the film is 100 % up to an aspect ratio of 15:1 and 40 % for aspect ratio of 40:1. The thickness per cycle, corresponding to the growth rate, was measured by Rutherford back scattering as a function of various key growth parameters, including TaCl5 and H exposure time and growth temperature. The maximum thickness per cycle values were below 0.1 ML, probably due to the steric hindrance for TaCl5 adsorption. Bilayer structures consisting of Cu films deposited by sputtering and ALD Ta films with various thicknesses were prepared and the diffusion barrier properties of ALD Ta films were investigated by various analysis techniques consisting of X-ray diffraction, elastic light scattering, and resistance analysis. The results were compared with Ta thin films deposited by sputtering with comparable thicknesses. Also, the growth of TaN films by PE-ALD using consecutive exposures of atomic H and activated N2 is presented.

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The Integration of Plasma Enhanced Atomic Layer Deposition (PEALD) of Tantalum-Based Thin Films for Copper Diffusion Barrier Applications

MRS Proceedings ◽

10.1557/proc-766-e10.4 ◽

2003 ◽

Vol 766 ◽

Author(s):

Degang Cheng ◽

Eric T. Eisenbraun

Keyword(s):

Atomic Layer Deposition ◽

Diffusion Barrier ◽

Hydrogen Plasma ◽

Atomic Layer ◽

Barrier Properties ◽

Tantalum Nitride ◽

Copper Metallization ◽

X Ray ◽

Layer Deposition ◽

Electron Spectrometry

AbstractA plasma-enhanced atomic layer deposition (PEALD) process for the growth of tantalumbased compounds is employed in integration studies for advanced copper metallization on a 200- mm wafer cluster tool platform. This process employs terbutylimido tris(diethylamido)tantalum (TBTDET) as precursor and hydrogen plasma as the reducing agent at a temperature of 250°C. Auger electron spectrometry, X-ray photoelectron spectrometry, and X-ray diffraction analyses indicate that the deposited films are carbide rich, and possess electrical resistivity as low as 250νΔcm, significantly lower than that of tantalum nitride deposited by conventional ALD or CVD using TBTDET and ammonia. PEALD Ta(C)N also possesses a strong resistance to oxidation, and possesses diffusion barrier properties superior to those of thermally grown TaN.

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Growth mechanism and diffusion barrier property of plasma-enhanced atomic layer deposition Ti–Si–N thin films

Journal of Vacuum Science & Technology B Microelectronics and Nanometer Structures Processing Measurement and Phenomena ◽

10.1116/1.2198846 ◽

2006 ◽

Vol 24 (3) ◽

pp. 1327 ◽

Cited By ~ 16

Author(s):

Jin-Seong Park ◽

Sang-Won Kang ◽

H. Kim

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

Growth Mechanism ◽

Diffusion Barrier ◽

Atomic Layer ◽

Barrier Property ◽

Layer Deposition ◽

And Diffusion

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Ru-Si-N Thin Films Prepared by Plasma Enhanced Atomic Layer Deposition as a Diffusion Barrier of Direct Plating of Cu

ECS Meeting Abstracts ◽

10.1149/ma2009-02/23/2040 ◽

2009 ◽

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

Diffusion Barrier ◽

Atomic Layer ◽

Direct Plating ◽

Layer Deposition

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Thermal atomic layer deposition of rhenium nitride and rhenium metal thin films using methyltrioxorhenium

Dalton Transactions ◽

10.1039/d1dt03454e ◽

2021 ◽

Author(s):

Stefan Cwik ◽

Keenan N. Woods ◽

S. Sameera Perera ◽

Mark J. Saly ◽

Thomas J. Knisley ◽

...

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

Atomic Layer ◽

Metal Thin Films ◽

Layer Deposition

The growth of rhenium nitride and rhenium metal thin films is presented using atomic layer deposition (ALD) with the precursors methyltrioxorhenium and 1,1-dimethylhydrazine. Saturative, self-limiting growth was determined at 340...

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Atomic Layer Deposition of Solid Lubricant Thin Films

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-63566 ◽

2005 ◽

Cited By ~ 2

Author(s):

T. W. Scharf ◽

S. V. Prasad ◽

M. T. Dugger ◽

T. M. Mayer

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Transition Metal ◽

Atomic Layer Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Atomic Layer ◽

Aspect Ratios ◽

Layer Deposition ◽

Vapor Deposition Technique

Tungsten disulphide (WS2) and molybdenum disulfide (MoS2), which belong to the family of transition metal dichalcogenides, are well known for their solid lubricating behavior. Thin films of MoS2 and WS2 exhibit extremely low coefficient of friction (COF ∼0.02 to 0.05) in dry environments, and are typically applied by sputter deposition, pulsed laser ablation, evaporation or chemical vapor deposition, which are essentially either line-of-sight or high temperature processes. With these techniques it is difficult to coat surfaces shadowed from the target, or uniformly coat sidewalls of three-dimensional or high aspect ratio structures. For applications such as micromechanical (MEMS) devices, where dimensions and separation tolerances are small, and aspect ratios are large, these traditional deposition techniques are inadequate. Atomic layer deposition (ALD) is a chemical vapor deposition technique that could overcome many of these problems by using sequential introduction of gaseous precursors and selective surface chemistry to achieve controlled growth at lower temperatures, but the chemistry needed to grow transition metal dichalcogenide films by ALD is not known.

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