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interdiffusion in group IV semiconductor material systems:applications,research methods and discoveries

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Science Bulletin 2019年第19期64卷 1436-1455页

作者： Guangrui(Maggie)Xia Department of Materials Engineering the University of British Columbia

Group IV semiconductor alloys and heterostructures such as Si Ge,Ge Sn,Ge/Si and Si Ge:C have been widely used and under extensive research for applications in major microelectronic and photonic devices.In the growth and processing of these materials,nanometer scale interdiffusion is common,which is generally undesirable for device performance.With higher Ge molar fractions and higher compressive strains,Si-Ge interdiffusion can be much faster than dopant diffusion.However,Si-Ge interdiffusion behaviors have not been well understood until recent years.Much less studies are available for Ge Sn.This review starts with basic properties and the applications of major group IV semiconductors,and then reviews the progress made so far on Si-Ge and Ge-Sn interdiffusion behaviors.Theories,experimental methods,design and practical considerations are discussed together with the key findings in this field.

关键词： Group IV semiconductors interdiffusion Modelling Si Ge materials and devices

interdiffusion KINETICS OF MISCIBLE POLYMER/POLYMER LAMINATES INVESTIGATED BY ATOMIC FORCE MICROSCOPY

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Chinese Journal of Polymer Science 2013年第6期31卷 870-878页

作者： Yong-gui Liao Meng-jun Peng Feng-zhen Liu 解孝林 Key Laboratory for Large-Format Battery Materials and System Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

The miscibility of poly（vinyl chloride）/poly（n-butyl methacrylate）（PVC/PnBMA） blend and the interdiffusion kinetics of PVC/PnBMA laminates have been investigated by differential scanning calorimetry （DSC） and atomic force microscopy （AFM）, respectively. This blend exhibited a lower critical solution temperature behavior. Below 120 ℃, DSC results showed each blend with different PVC contents exhibited only a single glass transition temperature which increased with PVC content, indicating that PVC and PnBMA were miscible. After PVC/PnBMA laminates were annealed at different temperature for different time, a smooth cross-section across interface was prepared by ultramicrotoming. Combined with topography and phase images of tapping mode AFM, the relative concentration profile, interface width and the relationship between interface width and annealing time could be obtained. In a regime of rubbery/rubbery interdiffusion, the diffusion obeyed a typical Fickian Case-I behavior where the interface width was proportional to the square root of annealing time. The mutual diffusion coefficient was in good agreement with that obtained from DSC and positron annihilation lifetime spectroscopy. However, in the regime of glassy/rubbery interdiffusion, the diffusion followed a typical Case-II behavior where the interface width was proportional to annealing time. These results imply that AFM is a reliable and powerful tool for the investigation of polymer/polymer interdiffusion at a level of polymer chain size.

关键词： Miscibility Polymer interface interdiffusion Kinetics Atomic force microscopy.

interdiffusion behavior between Cr and Zr and its effect on the microcracking behavior in the Cr-coated Zr-4 alloy

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Nuclear Science and Techniques 2021年第12期32卷 1-12页

作者： Ji-Shen Jiang Dong-Qing Wang Ming-Yue Du Xian-Feng Ma Chen-Xue Wang Xiu-Jie He Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

High-temperature chromium(Cr)-zirconium(Zr)interdiffusion commonly occurs in Cr-coated zircaloys applied for enhanced accident-tolerant fuel(ATF)claddings.Such interdiffusion changes the interfacial microstructure and thus the fracture mechanism of the coating under external loading.In this study,the interdiffusion behavior in a magnetron sputtered Cr coating deposited on a Zr-4 alloy was studied in a vacuum environment at 1160C.In addition,the effect of interdiffusion on the microcracking behavior of the Cr coating was determined by in situ three-point bending tests.The experimental results show that the interdiffusion behavior resulted in the formation of a ZrCr2 layer,accompanied by the consumption of Cr coating and interfacial roughening.The growth of the diffusion layer followed a nearly parabolic law with respect to annealing time,and the residual stress of the annealed coating decreased with increasing annealing time.Under external loading,a large number of cracks were generated in the brittle interlayer,and some interfacial cracks were formed and grew at the ZrCr2/Zr-4 interface.Despite the remarkable microcracks in the ZrCr2 layer,the vacuum-annealed Cr coating has significantly fewer cracks than the original coating,mainly because of the recrystallization of the coating during annealing.

关键词： Accident-tolerant fuel Surface coating interdiffusion Three-point bending test Crack propagation

interdiffusion in the Fe_2O_3-TiO_2 system

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International Journal of Minerals,Metallurgy and Materials 2013年第3期20卷 273-278页

作者： Zhong-shan Ren Xiao-jun Hu Shen-yang Li Xiang-xin Xue Kuo-chih Chou State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical Ecological Engineering University of Science and Technology Beijing School of Materials and Metallurgy Northeastern University

interdiffusion in the Fe203-TiO2 system was investigated by the diffusion couple method in the temperature range of 1323 to 1473 K. The diffusion concentration curves of Ti4＋ cations were obtained by electron probe microanalysis, according to which the Boltzmann-Matano method optimized by Broeder was used to calculate the interdiffusion coeffi- cients. The interdiffusion coefficients almost increased linearly with the mole fraction of Ti4＋ cations increasing, and they were in the range of 10-12-10-11cm2-s-1. The increase of temperature could also lead to the increase of the interdiffusion coefficients at a constant concentration of Ti4＋ cations. It was also found that the thickness growth of the diffusion layer obeyed the parabolic rate law.

关键词： interdiffusion titanium dioxide iron oxides diffusion couples electron probe microanalysis

Phase-field simulation of the effect of interaction among ordered domains on interdiffusion in Ni-Al-Cr alloys

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Chinese Physics B 2009年第10期18卷 4407-4412页

作者：张玉祥王锦程杨玉娟杨根仓周尧和 State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The effect of interaction among γ′ ordered domains on the interdiffusion process in γ＋γ′ and γ＋γ′/γ＋γ′ diffusion couples is investigated by using the phase-field method, in which bulk free energy and mobility are linked with thermodynamic and kinetic databases. Simulated results show that the interaction among γ′ ordered domains has great influence on the microstructure, the interdiffnsion velocity and the volume fraction ofγ′ phase on both sides of the diffusion couples.

关键词： interdiffusion phase-field method ordered domain Ni-Al-Cr

Oxidation and interdiffusion behavior of a germanium-modified silicide coating on an Nb–Si-based alloy

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 289-296页

作者： Jin-long Li Wan Wang Chun-gen Zhou Department of Materials Science and Engineering Beihang University Beijing 100191 China

To investigate the interdiffusion behavior of Ge-modified silicide coatings on an Nb–Si-based alloy substrate,the coating was oxidized at 1250°C for 5,10,20,50,or 100 h.The interfacial diffusion between the(Nb,X)(Si,Ge)_2(X = Ti,Cr,Hf) coating and the Nb–Si based alloy was also examined.The transitional layer is composed of(Ti,Nb)_5(Si,Ge)_4 and a small amount of(Nb,X)_5(Si,Ge)_3.With increasing oxidation time,the thickness of the transitional layer increases because of the diffusion of Si from the outer layer to the substrate,which obeys a parabolic rate law.The parabolic growth rate constant of the transitional layer under oxidation conditions is 2.018 μm×h^(-1/2).Moreover,the interdiffusion coefficients of Si in the transitional layer were determined from the interdiffusion fluxes calculated directly from experimental concentration profiles.

关键词： silicides coatings intermetallics oxidation interdiffusion

Cyclic Oxidation Behavior of an EB-PVD CoCrAlY Coating Influenced by Substrate/coating interdiffusion

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Chinese Journal of Aeronautics 2012年第5期25卷 796-803页

作者： LIANG Tianquan GUO Hongbo PENG Hui GONG Shengkai School of Materials Science and Engineering Beihang University Beijing 100191 China School of Materials Science and Engineering Guangxi University Nanning 530004 China

To reveal the influence of substrate/coating interdiffusion on the cyclic oxidation property of a metallic coating, cyclic oxida- tion behavior of an EB-PVD CoCrAIY coating on directionally solidified Ni-based superalloy DZ125 at 1 050℃ is investigated. The 40 μm thick CoCrA1Y coating has a cyclic oxidation life of around 160 h, and the oxidation constant is 1.915× 10^-7 mg4.cm^-8.s-1. However, severe spallation of the oxides containing Co, Cr, Ni, Ta and Ti occurs with longer cyclic oxidation. The degradation in oxidation resistance for the coating is related to the depletion of A1 due to the oxide spallation and interdiffu- sion. Severe interdiffusion between the coating and underlying substrate occurs at 1 050 ℃. The composition of the substrate has an important effect on the thermal cycling lifetime of the coating. The influencing mechanism is discussed.

关键词： CoCrA1Y coating cyclic oxidation degradation interdiffusion substrate composition

Oxidation Performance and interdiffusion Behavior of a Pt-Modified Aluminide Coating with Pre-deposition of Ni

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1490-1500页

作者： He Liu Shuai Li Cheng-Yang Jiang Chun-Tang Yu Ze-Bin Bao Sheng-Long Zhu Fu-Hui Wang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang 110819China

To refrain the interdiffusion of elements while holding good oxidation resistance,a(Ni,Pt)Al/Ni composite coating was prepared by sequential treatments of electroplating Ni and Pt and successive gaseous aluminization.In comparison with normal(Ni,Pt)Al coating,high-temperature performance of the composite coating was evaluated in isothermal oxidation test at 1100℃.Both the two coatings exhibited good resistance against high-temperature oxidation,but the interdiffusion of elements between composite coating and single-crystal(SC)superalloy substrate was greatly relieved,in which the thickness of secondary reaction zone(SRZ)and the amount of precipitated topologically close-packed phase in the SC alloy matrix were significantly decreased.Mechanisms responsible for delaying rate of coating degradation and SRZ growth/propagation are discussed.

关键词： Aluminide coating Oxidation interdiffusion Microstructure

Predicting interdiffusion in High Temperature Coatings

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Tsinghua Science and Technology 2005年第6期10卷 704-708页

作者： J. E. Morral Department of Materials Science and Engineering Ohio State University Columbus Ohio 43210 USA

interdiffusion can be a major cause of failure in coated parts that see service at elevated temperatures. Ways to measure the extent of interdiffusion and mathematical equations for predicting these measures are given. The equations are based on the error function solution to the diffusion equation and do not take into account variations of the diffusivity with composition. Also, when the substrate of the coating is multiphase, the equations do not take into account the precipitate morphology, but do take into account that precipitates can act as sinks or sources of solute as the average composition of the substrate varies. The equations are meant to be alloy design tools that indicate how changing substrate or coating chemistry will reduce the extent of interdiffusion.

关键词： interdiffusion high temperature coatings multicomponent diffusion multiphase diffusion coating design