Pulse-Modulated Plasma Etching of Copper Thin Films via CH3COOH/Ar

Pulse-modulated plasma etching of copper masked using SIO2 films was conducted via a CH3COOH/Ar. The etch characteristics were examined under pulse-modulated plasma. As the duty ratio of pulse decreased and the frequency of pulse increased, the etch selectivity and etch profile were improved. X-ray photoelectron spectroscopy and indicated that more copper oxides (Cu2O and CuO) and Cu(CH3COO)2 were formed using pulse-modulated plasma than those formed using continuous-wave (CW) plasma. As the concentration of CH3COOH gas in pulse-modulated plasma increased, the formation of these copper compounds increased, which improved the etch profiles. Optical emission spectroscopy confirmed that the active ingredients of the plasma increased with decreasing pulse duty ratio and increasing frequency. Therefore, the optimized pulsed plasma etching of copper via a CH3COOH/Ar gas provides better etch profile than that by CW plasma etching.

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Etch Characteristics of Nanoscale Patterned Magnetic Tunnel Junction Stacks Using Pulse-Modulated Radio Frequency Source Plasma

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17804 ◽

2020 ◽

Vol 20 (8) ◽

pp. 5131-5137

Author(s):

Jae Yong Lee ◽

Eun Tack Lim ◽

Jin Su Ryu ◽

Jae Sang Choi ◽

Chee Won Chung

Keyword(s):

Inductively Coupled Plasma ◽

Magnetic Tunnel Junction ◽

Optical Emission ◽

Pulse Frequency ◽

Duty Ratio ◽

Inductively Coupled ◽

Degree Of Anisotropy ◽

Ar Gas ◽

High Degree ◽

Etch Profile

Magnetic tunnel junctions (MTJs) patterned with 70 × 70 nm2 square arrays were etched in a CH4/O2/Ar gas mixture by pulse-modulated inductively coupled plasma reactive ion etching (ICPRIE). A good etch profile of MTJs with etch slope of approximately 82° was achieved by adjusting the on–off duty ratio of the plasma and pulse frequency. Langmuir probe analysis and optical emission spectroscopy confirmed that the balance between the formation of the passivation layer as an etch byproduct and sputtering effect is responsible for the etch selectivity and etch profile with a high degree of anisotropy. It is concluded that the application of pulse-modulated plasma on ICPRIE can be an effective method to obtain the anisotropic etch profile of nanometer-scale MTJs.

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Investigation of ETCH Profiles in Etching of PZT and Pt Thin Films

MRS Proceedings ◽

10.1557/proc-493-119 ◽

1997 ◽

Vol 493 ◽

Cited By ~ 4

Author(s):

Chee Won Chung ◽

Inyong Song ◽

Jong Sig Lee

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Secondary Ion Mass Spectrometry ◽

X Ray ◽

Inductively Coupled ◽

Gas Chemistry ◽

Pzt Films ◽

Ar Gas ◽

Etch Profile

ABSTRACTReactive ion etching of PbZrxTi1−xO3 (PZT) and Pt thin films was studied by using chlorine and fluorine gas chemistry in an Inductively Coupled Plasma (ICP). PZT films were etched by varying the etching parameters including coil RF power, dc-bias voltage to substrate, and gas pressure. Etching characteristics of PZT films were investigated in terms of etch rate, etch selectivity, etch profile. Etch profile along with etch anisotropy was observed as a function of etching parameter by field emission scanning electron microscopy (FESEM). For the understanding of etching mechanism, X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma (ICP) analysis for the film composition were utilized. Platinum thin films have been etched by using Cl2/Ar in an ICP for the development offence-free etching. The redeposited materials formed on the pattern sidewall by using Cl2/Ar gas combination were analyzed by X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS). We found that the redeposited material was mainly PtCh compound. Based on this result, SiCl4/Cl2/Ar gas chemistry has been proposed as a new etching gas and demonstrated good etching profile of Pt films without unwanted redeposition.

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Dry Etching Performance and Gas-Phase Parameters of C6F12O + Ar Plasma in Comparison with CF4 + Ar

Materials ◽

10.3390/ma14071595 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1595

Author(s):

Nomin Lim ◽

Yeon Sik Choi ◽

Alexander Efremov ◽

Kwang-Ho Kwon

Keyword(s):

Gas Phase ◽

Photoelectron Spectroscopy ◽

Reactive Ion Etching ◽

Research Work ◽

Optical Emission ◽

Plasma Parameters ◽

Ion Etching ◽

Ar Plasma ◽

Ar Gas ◽

Etching Selectivity

This research work deals with the comparative study of C6F12O + Ar and CF4 + Ar gas chemistries in respect to Si and SiO2 reactive-ion etching processes in a low power regime. Despite uncertain applicability of C6F12O as the fluorine-containing etchant gas, it is interesting because of the liquid (at room temperature) nature and weaker environmental impact (lower global warming potential). The combination of several experimental techniques (double Langmuir probe, optical emission spectroscopy, X-ray photoelectron spectroscopy) allowed one (a) to compare performances of given gas systems in respect to the reactive-ion etching of Si and SiO2; and (b) to associate the features of corresponding etching kinetics with those for gas-phase plasma parameters. It was found that both gas systems exhibit (a) similar changes in ion energy flux and F atom flux with variations on input RF power and gas pressure; (b) quite close polymerization abilities; and (c) identical behaviors of Si and SiO2 etching rates, as determined by the neutral-flux-limited regime of ion-assisted chemical reaction. Principal features of C6F12O + Ar plasma are only lower absolute etching rates (mainly due to the lower density and flux of F atoms) as well as some limitations in SiO2/Si etching selectivity.

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X-ray photoelectron spectroscopy of copper compounds

Molecular Physics ◽

10.1080/00268977200101961 ◽

1972 ◽

Vol 24 (4) ◽

pp. 861-877 ◽

Cited By ~ 411

Author(s):

D.C. Frost ◽

A. Ishitani ◽

C.A. McDowell

Keyword(s):

Photoelectron Spectroscopy ◽

X Ray ◽

Copper Compounds

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Cl2 Plasma — Si Surface Interactions in Plasma Etching: X-ray Photoelectron Spectroscopy After Etching, and Optical and Mass Spectrometry Methods During Etching

Plasma Processing of Semiconductors ◽

10.1007/978-94-011-5884-8_14 ◽

1997 ◽

pp. 243-275

Author(s):

V. M. Donnelly ◽

N. Layadi ◽

J. T. C. Lee ◽

I. P. Herman ◽

K. V. Guinn ◽

...

Keyword(s):

Mass Spectrometry ◽

Plasma Etching ◽

Photoelectron Spectroscopy ◽

Surface Interactions ◽

X Ray

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Structural and Fluorine Plasma Etching Behavior of Sputter-Deposition Yttrium Fluoride Film

Nanomaterials ◽

10.3390/nano8110936 ◽

2018 ◽

Vol 8 (11) ◽

pp. 936 ◽

Cited By ~ 4

Author(s):

Wei-Kai Wang ◽

Yu-Xiu Lin ◽

Yi-Jie Xu

Keyword(s):

Plasma Etching ◽

Photoelectron Spectroscopy ◽

Heating Temperature ◽

Working Pressure ◽

Etching Depth ◽

Yttrium Fluoride ◽

X Ray ◽

Substrate Heating ◽

Etching Behavior ◽

Etched Surface

Yttrium fluoride (YF3) films were grown on sapphire substrate by a radio frequency magnetron using a commercial ceramic target in a vacuum chamber. The structure, composition, and plasma etching behavior of the films were systematically investigated. The YF3 film was deposited at a working pressure of 5 mTorr and an RF power of 150 W. The substrate-heating temperature was increased from 400 to 700 °C in increments of 100 °C. High-resolution transmission electron microscopy (HRTEM) and X-ray diffraction results confirmed an orthorhombic YF3 structure was obtained at a substrate temperature of 700 °C for 2 h. X-ray photoelectron spectroscopy revealed a strongly fluorinated bond (Y–F bond) on the etched surface of the YF3 films. HRTEM analysis also revealed that the YF3 films became yttrium-oxyfluorinated after exposure to fluorocarbon plasma. The etching depth was three times lower on YF3 film than on Al2O3 plate. These results showed that the YF3 films have excellent erosion resistance properties compared to Al2O3 plates.

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Plasma electrolytic oxidation of metals

Journal of the Serbian Chemical Society ◽

10.2298/jsc121126129s ◽

2013 ◽

Vol 78 (5) ◽

pp. 713-716 ◽

Cited By ~ 5

Author(s):

Stevan Stojadinovic

Keyword(s):

Photoelectron Spectroscopy ◽

Plasma Electrolytic Oxidation ◽

Dielectric Breakdown ◽

Optical Emission ◽

Active Surface ◽

Spatial Density ◽

Oxide Coatings ◽

X Ray ◽

Electrolytic Oxidation ◽

Plasma Electrolytic

In this lecture results of the investigation of plasma electrolytic oxidation (PEO) process on some metals (aluminum, titanium, tantalum, magnesium, and zirconium) were presented. Whole process involves anodizing metals above the dielectric breakdown voltage where numerous micro-discharges are generated continuously over the coating surface. For the characterization of PEO process optical emission spectroscopy and real-time imaging were used. These investigations enabled the determination of electron temperature, electron number density, spatial density of micro-discharges, the active surface covered by micro-discharges, and dimensional distribution of micro-discharges at various stages of PEO process. Special attention was focused on the results of the study of the morphology, chemical, and phase composition of oxide layers obtained by PEO process on aluminum, tantalum, and titanium in electrolytes containing tungsten. Physicochemical methodes: atomic force microscopy (AFM), scanning electron microscopy (SEM-EDS), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and Raman spectroscopy served as tools for examining obtained oxide coatings. Also, the application of the obtained oxide coatings, especially the application of TiO2/WO3 coatings in photocatalysis, were discussed.

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Segregation of Cu on Etched and Non-Etched Al(Cu) Surface

MRS Proceedings ◽

10.1557/proc-516-77 ◽

1998 ◽

Vol 516 ◽

Cited By ~ 4

Author(s):

Hua Li ◽

Karen Maex ◽

Bert Brijs ◽

Thierry Conard ◽

Wilfried Vandervorst ◽

...

Keyword(s):

Plasma Etching ◽

Photoelectron Spectroscopy ◽

Rutherford Backscattering Spectrometry ◽

Native Oxide ◽

Interface Area ◽

X Ray ◽

Origin And Evolution ◽

Significant Enrichment ◽

Segregation Phenomenon ◽

Al Oxide

AbstractIn this paper, we have studied the segregation phenomenon of Cu on the surfaces of patterned lines, dry-etched films and non-etched films, by using X-ray photoelectron spectroscopy and lower energy Rutherford Backscattering Spectrometry. Significant enrichment of Cu is found on the sidewall of the lines. Annealing at 350°C and above cause the disappearance of this enrichment. Origin and evolution of this Cu enrichment have been investigated on films taken out from different steps of the etching process. It has been found that most of the Cu products induced by the plasma etching are CuCl and CuCl2 and they are removed mostly from the top Al oxide layer by the strip process. On the interface area between Al and the native oxide, considerable quantities of etched induced Cu are retained. This Cu is identified to be mainly metallic Cu. Different from the mechanism explained above, thermal annealing can also cause Cu segregation. We have found that Cu atoms diffuse into the native Al oxide where they form Cu2O.

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Corrosion Phenomena on the Grain Boundary of AlCu FIlms After Plasma Etching

MRS Proceedings ◽

10.1557/proc-473-393 ◽

1997 ◽

Vol 473 ◽

Author(s):

C. L. Kim ◽

K. H. Kwon ◽

S. J. Yu ◽

H. J. Kim ◽

E. G. Chang

Keyword(s):

Grain Boundary ◽

Plasma Etching ◽

Photoelectron Spectroscopy ◽

Electron Spectroscopy ◽

Auger Electron ◽

X Ray ◽

Gas Plasma ◽

Point Analysis ◽

Selective Corrosion ◽

Scanning Electron

ABSTRACTThe effect of grain boundary on the corrosion of Al(Cu 1%) etched using SiCl4/Cl2/He/CHF3 gas plasma has been evaluated with XPS (X-ray photoelectron spectroscopy), SEM (scanning electron microscopy) and AES (Auger electron spectroscopy). It was found with SEM that the surface of Al(Cu 1 %) mainly corroded at the grain boundary. Using AES point analysis, the cause of selective corrosion at the grain boundary of Al(Cu 1 %) has been investigated. The results of AES indicated that the contents of F and Cl have made a difference at the analyzed positions. This seems to result from the imperfect crystalline structure of Al(Cu 1%) grain boundary. It was also confirmed that F has passivated the Cl at the grain boundary. The SEM and XPS results implied that Cl incorporated in the grain boundary of polycrystalline Al(Cu 1%) film accelerated the corrosion and could not be easily removed by the subsequent SF6 plasma treatment.

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