Thermal Oxidation of Cu Interconnects Capped with CoWP

AbstractThe thermal oxidation of Cu interconnects, at 350°C in air, has been studied as a function of thickness of a CoWP capping layer. For thin CoWP layers (25 nm), a thick oxide layer (200 nm) is formed which is mainly composed of Cu20. For thick CoWP layers (50 nm), the oxide layer is much thinner (36 nm) and is mainly composed of CoO. For both CoWP thicknesses, depletion of the underlying Cu is often observed after oxidation and whisker growth is often observed on the surface. The results are consistent with an oxidation mechanism where metal is the dominant diffusing species. For thin CoWP layers, Cu diffuses more quickly to the surface than Co, and therefore mainly Cu oxides are formed. For thick CoWP layers, the Cu diffusion to the surface is greatly reduced, and as a result, mainly Co oxides are formed. These results indicate that CoWP is not a good barrier for thermal oxidation, so high temperature exposure to oxidizing ambients must be minimized during processing of integrated circuits where CoWP is used instead of a dielectric barrier.

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Analysis on Failure of Oxide Layer of T91 High Temperature Superheater Tube

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1070-1072.505 ◽

2014 ◽

Vol 1070-1072 ◽

pp. 505-511

Author(s):

Shan Shan Zhang ◽

Guang Chen ◽

Chang Ming Li ◽

Da Hu

Keyword(s):

High Temperature ◽

Dissolved Oxygen ◽

Oxide Layer ◽

Outer Layer ◽

Oxidation Mechanism ◽

Middle Layer ◽

Compact Structure ◽

Protective Properties ◽

Superheater Tube ◽

Temperature Operating

The reason why the failure protective properties of the oxide layer of T91 high temperature superheater tube were analyzed in this study. The microstructure of the oxide layer of T91 high temperature superheater tube was observed by scanning electron microscope (SEM) and the morphological features of it was also analyzed. The concentrations of alloy elements in the section of internal tube were quantitatively analyzed using Energy Dispersive System (EDS). The results showed that the oxide layer of T91 tube can be divided into three layers: inner layer, middle layer and outer layer. The inner layer was formed by chromium rich oxide with compact structure. The middle layer was made up by porous oxide with loose structure. The outer layer was identified as Fe2O3. When the content of dissolved oxygen in steam was excessive, the apparent peeling marks will be appeared in the oxide layer of T91 high temperature superheater tube and the distribution of alloy elements in the oxide layer will present obvious proliferation, migration and enrichment phenomenon. Two different mechanisms (steam oxidation mechanism and oxygen oxidation mechanism) will exercise different influences on the structure and protective properties of the oxide layer: when steam contained dissolved oxygen, the oxide layer will be peroxidated by steam and the structure of oxide layer will be broken; When the tube was over-temperature operating, the oxide layer will be oxidated by oxygen.

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A Stochastic Model of Oxidation Mechanism on High Temperature Corrosion of Stainless Steel

Materials, Nondestructive Evaluation, and Pressure Vessels and Piping ◽

10.1115/imece2006-15167 ◽

2006 ◽

Author(s):

Huajun Chen ◽

Yitung Chen ◽

Hsuan-Tsung Hsieh

Keyword(s):

High Temperature ◽

Oxide Layer ◽

Present Model ◽

Oxidation Mechanism ◽

High Temperature Corrosion ◽

Iron Species ◽

Corrosive Liquid ◽

Model Mapping ◽

Wagner Theory

To interpret the role of diffusion and reaction process, a cellular automaton model, which combines the surface growth and internal oxidation, was developed to explain the oxidation mechanism of stainless steels in high temperature corrosive liquid metal environment. In this model, three main processes, which include the corrosion of the substrate, the diffusion of iron species across the oxide layer and precipitation of iron on the oxide layer, are simulated. The diffusion process is simulated by random walk model. Mapping between present model and Wagner theory has been created. The gross features concerning the evolution of the involved process were founded.

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Characteristics of Oxide Layer Grown on Gallium Arsenide Using 2.8-eV Translational Energy Atomic Oxygen

MRS Proceedings ◽

10.1557/proc-204-59 ◽

1990 ◽

Vol 204 ◽

Cited By ~ 1

Author(s):

J.B. Cross ◽

M.A. Hoffbauer ◽

J.D. Farr ◽

O.J. Glembocki ◽

V.M. Bermudez

Keyword(s):

Raman Spectroscopy ◽

Gallium Arsenide ◽

High Temperature ◽

Thermal Oxidation ◽

Oxide Layer ◽

Atomic Oxygen ◽

Oxidation States ◽

Translational Energy ◽

Oxidation Processes ◽

As Species

ABSTRACTOxide layers that are thick (>200 Å and uniform have been produced on GaAs (110) and (100) by reacting the substrate (Ts<160°C) with high translational energy (1-3 eV) neutral atomic oxygen at flux levels of∼50 monolayers/second. The Ga and As species are formed in their highest oxidation states, which implies formation of either Ga2O3 and As2O5 or GaAsO4. Raman spectroscopy indicates that there is no metallic (amorphous or crystalline) As in the oxide or at the interface between the oxide and substrate and that there is no appreciable oxidation induced disorder of the substrate as is seen in high temperature thermal oxidation processes.

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High-Temperature Oxidation Performance of 4Cr4Mo2NiMnSiV Hot Die Steel

Materials Science ◽

10.5755/j02.ms.25245 ◽

2021 ◽

Author(s):

Renheng HAN ◽

Ning LI ◽

Ziming BAO ◽

Xinjian HU ◽

Hexin ZHANG ◽

...

Keyword(s):

High Temperature ◽

Oxide Layer ◽

High Temperature Oxidation ◽

Metallic Matrix ◽

Oxidation Mechanism ◽

Surface Oxidation ◽

Ambient Atmosphere ◽

Temperature Oxidation ◽

Die Steel ◽

Hot Working Die Steel

A new type of hot working die steel was designed by using JMatPro, and high-temperature oxidation tests were carried out in the ambient atmosphere at 600 ℃ and 700 ℃. The heat treatment process and oxidation mechanism of the designed 4Cr4Mo2NiMnSiV steel were studied in detail. XRD, SEM and EDS were used to analyze the crystallographic phases, surface and cross-section morphologies of the oxide films. The results show that the main phases in the 4Cr4Mo2NiMnSiV steel were γ and α + δ. During the high-temperature oxidation, oxidation of the Fe outer layer and Cr inner layer occurred. After oxidation at 600℃, the surface oxidation layer comprised a monolayer with an uneven morphology. The surface oxide film had two layers after oxidation at 700℃. The outer oxide layer mainly contained Fe2O3 and Fe3O4, while the inner oxide layer mainly contained Cr2O3. The microstructure was relatively regular and had a significant effect on the protection of the metallic matrix. When oxidized, the 4Cr4Mo2NiMnSiV alloy steel easily formed protective layers, such as Cr2O3 and SiO2, so that the test steel had excellent oxidation resistance at high temperatures.

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Shear Force Effects on Sidewall Penetration of Extended Dislocations in Phosphorus Implanted Emitters

MRS Proceedings ◽

10.1557/proc-14-389 ◽

1982 ◽

Vol 14 ◽

Cited By ~ 1

Author(s):

W. F. Tseng ◽

G. E. Davis

Keyword(s):

High Temperature ◽

Oxide Layer ◽

Shear Force ◽

Compressive Force ◽

Surface Force ◽

Excess Noise ◽

Dislocation Network ◽

Lattice Contraction ◽

Temperature Heat ◽

Thick Oxide Layer

ABSTRACTPhosphorus implanted emitters are known to have a dislocation network formed to relieve the strain caused by the lattice contraction of solute phosphorus ir, silicon. The extension of the dislocation network into the emitter-base regior, has also been related to the degradation of leakage current and the generatiol, of excess noise in an NPN bipolar transistor. The penetration of the extendeot dislocation network is shown in this paper to be related to a shear force. The shear force is the resultant of the compressive force generated from the solute phosphorus and an induced surface force generated from the thick oxide layer over the emitter formed during high temperature heat treatments. This shear force can pull the dislocation network through the junction sidewall.

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High Temperature Oxidation Mechanism of TiAl-W-Si Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.817 ◽

2004 ◽

Vol 449-452 ◽

pp. 817-820 ◽

Cited By ~ 3

Author(s):

Dong Bok Lee ◽

Seung Wan Woo

Keyword(s):

High Temperature ◽

Oxide Layer ◽

Mixed Layer ◽

Barrier Layer ◽

High Temperature Oxidation ◽

Oxidation Mechanism ◽

Temperature Oxidation ◽

Outward Diffusion

The oxidation of Ti-(43~52%)Al-2%W-(0~0.5%)Si alloys between 900 and 1050°C in air progressed via the outward diffusion of Ti ions to form the outer TiO2layer, and the inward transport of oxygen to form the inner (TiO2+Al2O3) mixed layer, between which the intermediate Al2O3barrier layer existed. Tungsten tended to diffuse inward to be incorporated below the intermediate Al2O3layer, while Si outward to exist over the entire oxide layer. Both W and Si tended to be dissolved in the oxide layer, rather than forming independent oxides.

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Oxidation Protection of Multiphase Mo-Containing γ-TiAl-Based Alloys under Cyclic Test Conditions

MRS Proceedings ◽

10.1557/opl.2015.160 ◽

2015 ◽

Vol 1760 ◽

Cited By ~ 1

Author(s):

A. Donchev ◽

R. Pflumm ◽

M. Galetz ◽

S. Mayer ◽

H. Clemens ◽

...

Keyword(s):

High Temperature ◽

Oxide Scale ◽

Mixed Oxide ◽

Titanium Aluminides ◽

Oxidation Mechanism ◽

Β Phase ◽

Test Conditions ◽

Free Model ◽

Temperature Exposure ◽

First Time

ABSTRACTIntermetallic titanium aluminides solidifying via the disordered β-phase are of great interest for several high-temperature applications in automotive and aircraft industries. In this paper the thermocyclic oxidation behavior of three β-solidifying γ-TiAl-based alloys at 800°C and 900°C in air, with and without fluorine treatment, is reported for the first time. The behavior of the well-known TNM alloy (Ti-43.5Al-4Nb-1Mo-0.1B, in at.%) is compared with that of two Nb-free model alloys which contain different amounts of Mo (Ti-44Al-3Mo and Ti-44Al-7Mo, in at.%). During thermocyclic high-temperature exposure in air a mixed oxide scale develops on all three untreated alloys. Small additions of fluorine in the subsurface region of the alloys change the oxidation mechanism from mixed oxide scale formation to alumina at both temperatures. The oxidation resistance of the fluorine treated samples was significantly improved compared to the untreated samples.

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Novel protection solutions against environmental attack for light weight high temperature materials

MRS Proceedings ◽

10.1557/opl.2013.153 ◽

2013 ◽

Vol 1492 ◽

pp. 155-160

Author(s):

Alexander Donchev ◽

Michael Schütze

Keyword(s):

High Temperature ◽

Elevated Temperatures ◽

Oxidation Mechanism ◽

Transport Systems ◽

Surface Zone ◽

Light Weight ◽

Alumina Layer ◽

High Temperature Exposure ◽

Temperature Capability ◽

Temperature Exposure

ABSTRACTThe use of light weight structural materials such as titanium in transport systems like aero planes leads to a significant reduction in fuel consumption. However, titanium and its alloys cannot be used at elevated temperatures above 500°C for several reasons. Today aero engine compressors are made of a mixture of light Ti- and heavy Ni-alloys. The improvement of Ti-alloys to withstand the conditions in the high pressure compressor i.e. temperatures above 500°C would enable the manufacturing of a compressor from titanium as a whole with all its associated benefits. Intermetallic TiAl-alloys are another class of light weight materials for several high temperature applications. The use of TiAl as low pressure turbine (LPT) blades in the last sections of a large jet engine could save up to 150 kg of weight. In the last sections of the LPT the temperature is quite moderate (max. 650°C). The improvement of the high temperature capability of TiAl would allow its use in hotter sections of the engine with additional weight reduction. Similarly, the response performance of TiAl-turbocharger rotors in automotive engines would be much faster compared to the heavy Ni-based alloys used today. Furthermore higher rotation speeds are possible. Due to the novel so called fluorine effect the oxidation mechanism of TiAl can be altered. Fluorine-treated TiAl-components are protected by an alumina layer formed during high temperature exposure in oxidizing environments. This effect can be transferred to Ti-base materials if they are enriched with aluminum in a thin surface zone. The concepts and the results of high temperature exposure experiments of treated Ti- and TiAl-specimens are presented in this paper. They are discussed in the view of a use for real components.

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Change of Oxidation Mechanisms by Laser Chemical Machined Rim Zone Modifications of 42CrMo4 Steel

Materials ◽

10.3390/ma14143910 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3910

Author(s):

Alexander Schupp ◽

René Daniel Pütz ◽

Oliver Beyss ◽

Lucas-Hermann Beste ◽

Tim Radel ◽

...

Keyword(s):

High Temperature ◽

Oxide Layer ◽

Manufacturing Process ◽

High Temperature Oxidation ◽

Oxidation Mechanism ◽

Metallic Surface ◽

Temperature Oxidation ◽

In Situ Xrd ◽

42Crmo4 Steel ◽

Oxidation Properties

The oxidation mechanism of metals depends, among other factors, on the surface integrity. The surface and rim zone properties are often determined by the manufacturing process that was used to machine the material. Laser chemical machining (LCM) is a manufacturing process that uses laser radiation as a localized and selective heat source to activate a chemical reaction between an electrolyte and a metallic surface. The objective of this work is first to investigate how different LCM processes affect the rim zone properties of 42CrMo4. For this purpose, the surface chemistry is analyzed by EDS and XPS, phases and residual stresses are determined by XRD, and the morphology is investigated by SEM. Second, the influence of these modified rim zones on the oxidation properties of the steel at 500 °C in air is to be demonstrated in oxidation tests by in situ XRD and subsequent SEM/EDS investigations. A decisive influence of the oxides formed on the surface of 42CrMo4 during LCM in different electrolytes (NaNO3 solution and H3PO4) at two different laser powers on the high-temperature oxidation properties was demonstrated. These oxides were supposed to act as nucleation sites for oxide layer formation at 500 °C and led to an overall increase in oxide layer thickness after high-temperature oxidation compared to non-LCM-processed surfaces.

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Structural changes in silicon-on-insulator material during post-implantation annealing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145054 ◽

1986 ◽

Vol 44 ◽

pp. 736-737

Author(s):

C. O. Jung ◽

S. J. Krause ◽

S.R. Wilson

Keyword(s):

Integrated Circuits ◽

Oxide Layer ◽

High Speed ◽

Structural Changes ◽

Device Fabrication ◽

Silicon On Insulator ◽

High Quality ◽

Radiation Hardened ◽

Post Implantation ◽

Very High

Silicon-on-insulator (SOI) structures have excellent potential for future use in radiation hardened and high speed integrated circuits. For device fabrication in SOI material a high quality superficial Si layer above a buried oxide layer is required. Recently, Celler et al. reported that post-implantation annealing of oxygen implanted SOI at very high temperatures would eliminate virtually all defects and precipiates in the superficial Si layer. In this work we are reporting on the effect of three different post implantation annealing cycles on the structure of oxygen implanted SOI samples which were implanted under the same conditions.

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