Kinetics Of Abnormal Grain Growth Research Articles

Recent advances in the kinetics of normal/abnormal grain growth: a review

Recent progress in the kinetics of grain coarsening and abnormal grain growth (AGG) is presented in this overview article. The factors affecting the kinetics of grain growth is reviewed with the emphasis on the recent findings on the solute drag and Zener pinning effects as well as the special case of duplex alloys, where the latter is discussed for the behavior of dual-phase steels during intercritical annealing. The common isothermal kinetics models for grain growth are listed, which is followed by the critical discussion on the simplifications and the commonly used methods for the determination of grain growth exponent (n) and activation energy (Q). The obtained values of n and Q for several classes of important engineering alloys such as microalloyed steels, stainless steels, magnesium alloys, aluminum alloys, titanium alloys, and high-entropy alloys are summarized with the discussion on the obtained values of kinetics parameters and their deviation from the theoretical expectations. Finally, the factors leading to AGG (such as the coarsening and dissolution of pinning particles and the crystallographic texture), the proposed mechanisms (such as the solid-state wetting and the grain boundary faceting/defaceting phenomena), and the kinetics of AGG (based on the empirical power law and the similarity of AGG to primary recrystallization in the form of secondary recrystallization) are reviewed. This overview can shed light on the understanding of grain growth and its effects.

Abnormal grain growth in a double-sided friction-stir welded Al-Mg-Si alloy

In this work, a standard T6 tempering (involving solution annealing followed by artificial aging) was employed to a fine-grained Al-Mg-Si alloy produced by double-sided friction-stir welding (FSW). The material was found to exhibit abnormal grain growth, thus demonstrating a relatively low thermal stability. The kinetics of abnormal grain growth in the joint was studied.

Describing the Kinetics of Abnormal Grain Growth in Nanocrystalline and Submicrocrystalline Nickel, Based on First-Order Phase Transition Representations

The growth of grains in nano- and submicrocrystalline nickel produced via equal channel angular pressing is investigated under conditions of non-isothermal annealing using differential scanning calorimetry and transmission electron microscopy. Both types of the material exhibit abnormal grain growth that can be described in terms of the Johnson–Mehl–Avrami formalism.

Thermal Annealing and Impurities Incorporation of Electrodeposited Cobalt Thin Film

Cobalt has recently attracted much attention as it is replacing copper in the ground rule metal level in advanced interconnects to minimize the resistivity increase in small features1. Defect-free filling of Co in small features has been demonstrated using various commercial additives2-4. Annealing has been used to further decrease and stabilize the resistivity of lines5. It is well known from copper studies that additives in electrolytes will not only be incorporated into the film as impurities but also affect the grain structures and resistivity of deposited film6, 7. Post deposition annealing has been used to further grow the grains and to influence the resistivity and reliability of lines and vias8. In this report, we use several different additives including dimethylglyoxime (DMG), sodium chloride (NaCl), and sodium 3-mercapto-1-propanesulfonate (MPS-Na) to study their individual and synergistic effects on impurity incorporation (C, N, Cl, S) in cobalt thin films. The film morphology, resistivity, crystallographic structure, and the impurity distribution were also investigated. Figures 1 (a) and (b) show the top-down SEM micrographs of two cobalt films deposited with different combinations of additives, one with 100 ppm DMG and 100 ppm MPS-Na, and the other with 100 ppm DMG and 100 ppm NaCl. A strong influence of additives on the morphology of Co films was observed. Figure 1 (c) shows the film sheet resistance change upon 300 C anneal in vacuum. The resistance decreases along the annealing time, but quickly settles within the first 2 hours except for the film deposited with a combination of the three additives (red line), 100 ppm DMG, 100 ppm NaCl, and 100 ppm MPS-Na. The later not only shows a much higher as deposited sheet resistance but also took a much longer 6 hours for the resistance to stabilize. Secondary ion mass spectroscopy (SIMS) was also used to quantify the impurities in the Co films. The resistivity change upon annealing will be discussed in detail in conjunction with the impurity and grain structure analysis. REFERENCES Gall, D., Electron mean free path in elemental metals. Journal of Applied Physics 2016, 119 (8), 085101.Rigsby, M. A.; Brogan, L. J.; Doubina, N. V.; Liu, Y.; Opocensky, E. C.; Spurlin, T. A.; Zhou, J.; Reid, J. D., Superconformal Cobalt Fill through the Use of Sacrificial Oxidants. ECS Transactions 2017, 80 (10), 767-776.Wafula, F.; Wu, J.; Branagan, S.; Suzuki, H.; Gracias, A.; van Eisden, J. In Electrolytic Cobalt Fill of Sub-5 nm Node Interconnect Features, 2018 IEEE International Interconnect Technology Conference (IITC), IEEE: 2018; pp 123-125.Kelly, J.; Chen, J.-C.; Huang, H.; Hu, C.; Liniger, E.; Patlolla, R.; Peethala, B.; Adusumilli, P.; Shobha, H.; Nogami, T. In Experimental study of nanoscale Co damascene BEOL interconnect structures, Interconnect Technology Conference/Advanced Metallization Conference (IITC/AMC), 2016 IEEE International, IEEE: 2016; pp 40-42.Kelly, J.; Kamineni, V.; Lin, X.; Pacquette, A.; Hopstaken, M.; Liang, Y.; Amanapu, H.; Peethala, B.; Jiang, L.; Demarest, J., Annealing and Impurity Effects in Co Thin Films for MOL Contact and BEOL Metallization. Journal of The Electrochemical Society 2019, 166 (1), D3100-D3109.Hau-Riege, S. P.; Thompson, C. V., In situ transmission electron microscope studies of the kinetics of abnormal grain growth in electroplated copper films. Applied Physics Letters 2000, 76 (3), 309-311.Zhang, W.; Brongersma, S.; Heylen, N.; Beyer, G.; Vandervorst, W.; Maex, K., Geometry effect on impurity incorporation and grain growth in narrow copper lines. Journal of The Electrochemical Society 2005, 152 (12), C832-C837.Ryu, C.; Kwon, K.-W.; Loke, A. L.; Lee, H.; Nogami, T.; Dubin, V. M.; Kavari, R. A.; Ray, G. W.; Wong, S. S., Microstructure and reliability of copper interconnects. IEEE transactions on electron devices 1999, 46 (6), 1113-1120. Figure 1

Abnormal and post-abnormal austenite grain growth kinetics in Nb–Ti microalloyed steels

The kinetics of abnormal grain growth in austenite was examined in microalloyed steel containing Nb and Ti additions. Abnormal grain growth was triggered by the dissolution of microalloyed carbonitrides during reheating. The progress of abnormal grain growth was determined at 1200, 1300 and 1400°C. Post-abnormal grain growth was defined as the grain growth process which takes place once all of the original fine grains have been consumed by the abnormal grains. The post-abnormal grain growth kinetics appeared to follow a simple parabolic law. The parabolic constant needed to describe post-abnormal grain growth in the present alloy was three times larger than that needed to describe normal grain growth in a similar alloy without Nb and Ti additions. The possible origins of this effect are briefly discussed.On a examiné la cinétique de croissance anormale de grain dans l'austénite d'acier micro-allié contenant des additions de Nb et de Ti. La croissance anormale de grain était déclenchée par la dissolution des carbonitrures micro-alliés lors du réchauffage. On a déterminé le progrès de la croissance anormale de grain à 1200°C, 1300°C et 1400°C. La croissance post-anormale de grain était définie comme le processus de croissance de grain qui a lieu une fois que tous les grains fins originaux ont été consommés par les grains anormaux. La cinétique de la croissance postanormale de grain semble suivre une simple loi parabolique. La constante parabolique nécessaire pour décrire la croissance post-anormale de s grain dans le présent alliage était trois fois plus grande que celle qui est nécessaire pour décrire la croissance normale de grain dans un alliage semblable sans additions de Nb et de Ti. On discute brièvement de l'origine possible de cet effet.

Computer Simulation of Grain Growth in Three Dimensions by the Phase Field Model with Anisotropic Grain-Boundary Mobilities

The kinetics and topology of grain growth in three dimensions were simulated using a phase-field model with anisotropic grain-boundary mobilities. In order to perform large scale calculations we applied both modifications of algorithms and parallel coding techniques to the Fan and Chen's phase-field algorithm. Kinetics of abnormal grain growth is presented. It is observed that the grains of a minor component which are at the beginning surrounded preferentially by boundaries of high mobility grow faster than the grains of a major component until the texture reverses completely. Additionally, topological results of grain structures, such as grain size distributions and grain face distributions, are discussed

Three-dimensional phase field simulation of the effect of anisotropy in grain-boundary mobility on growth kinetics and morphology of grain structure

The kinetics and topology of grain growth in three dimensions have been simulated using a phase-field model with anisotropic grain-boundary mobilities. In order to perform large scale calculations we have applied both modifications of algorithms and parallel coding techniques to Fan and Chen’s phase-field algorithm. The kinetics of abnormal grain growth together with isotropic grain growth is presented. It is observed that the grains of a minor component which are at the beginning surrounded preferentially by boundaries with high mobility grow faster than the grains of a major component until the texture reverses completely. In our simulation program, data arrays for storing orientation field variables are divided into each message passing interface (MPI) domain, and only the information about the cluster enumeration is shared with whole system. This enables us to perform large scale calculations such as 3203 grid points. In order to follow up the time-dependent growth exponent and distribution functions in a material with a strong texture, a large scale calculation is indispensable.

Effect of the Liquid‐Forming Additive Content on the Kinetics of Abnormal Grain Growth in Alumina

Alumina specimens with various amounts of CaO and SiO2 (1:2 ratio) were prepared, and their abnormal grain growth (AGG) kinetics were investigated. A plot of the area fraction covered by abnormal grains versus log (sintering time) had a sigmoidal shape with an apparent incubation period before the onset of AGG. The overall kinetics of AGG was similar to that of a phase transformation controlled by nucleation and growth. The incubation time and the end point of AGG were strongly dependent on the amount of liquid‐forming additives. Correspondingly, the final microstructure was affected by the liquid content: a large grain size and a high aspect ratio at low liquid content and a small grain size and a low aspect ratio at high liquid content.

Influence of primary annealing condition on texture development in grain oriented electrical steels

The development of texture and microstructure in two kinds of conventional grain oriented electrical steels, which were annealed at different primary annealing temperature, were investigated. The specimens were analyzed using Orientation Distribution Function (ODF), optical microscopy and OIM (Orientation Imaging Microscopy). The size distributions of AlN precipitates, which were used as grain growth inhibitors, were investigated using transmission electron microscope (TEM) and an image analyzer. The influence of primary annealing conditions on the secondary recrystallization in conventional grain oriented electrical steels was discussed based on information on precipitate distributions and the kinetics of abnormal grain growth of Goss grains. When the high energy boundary theory and the driving force for the Goss grain growth are considered, it is possible to explain the reason for significant improvement of the final texture and magnetic properties in the specimen that was recovered before the final annealing compared to the specimen that was recrystallized.

In situ transmission electron microscope studies of the kinetics of abnormal grain growth in electroplated copper films

We have performed in situ transmission electron microscopy studies of abnormal grain growth in electroplated copper films at room temperature and 55 °C, starting minutes after the plating process by electroplating directly onto electron-transparent membranes. A kinetic analysis indicates that the grains that grow abnormally, reject impurities as they grow, so that the impurities accumulate in (and must diffuse through) the untransformed matrix. This suggests that while impurities impair normal grain growth, impurity rejection contributes to the energetics that drive abnormal grain growth. This result also indicates that removal of impurities from the film can control the kinetics of the transformation to large-grained structures.

Abnormal grain growth in copper films during magnetically enhanced plasma processing

The kinetics of grain growth in thin copper films during magnetically enhanced (ME) plasma processing is monitored. Transmission electron microscopy (TEM) results suggest microstructural evolution characteristic of abnormal grain growth in these films. The kinetics of abnormal grain growth appears to depend on gas pressure in the reactor.

Kinetics of abnormal grain growth in pure iron

Grain growth after primary recrystallization in unstrained and strained specimens of pure iron is examined during isothermal anneals at three different temperatures (664, 680, 690° C). Undeformed specimens undergo continuous grain growth, while the deformed ones show a stage of rapid discontinuous growth. The peculiar characteristics of the abnormal growth kinetics, and in particular the presence of three well-defined stages of growth, are brought out by plotting, versus annealing time, the ratio between the mean grain diameters of deformed and undeformed samples. The parametersn (exponent of the kinetic equation) andQ (apparent activation energy) are determined.