Influence of parameters of the pulsating current (PC) regime on morphological, structural and hardness characteristics of copper coatings electrodeposited on Si(111)

Electrodeposition of Cu was performed on Si(111) by the pulsating current (PC) regime in the range of the average current densities (jav) between 15 and 70 mA cm-2 . The selected values of the average current densities were attained by varying either pause duration (tp: 28.3, 15, 7.5 and 5 ms, i.e. jav: 15, 25, 40 and 50 mA cm-2 for the constant values of deposition pulse of 5 ms and current density amplitude (jA) of 100 mA cm-2) or amplitude of the current density (jA: 120 and 140 mA cm-2 , i.e. jav: 60 and 70 mA cm-2 for the constant values of deposition pulse of 5 ms and pause duration of 5 ms). Morphological and structural characteristics of the obtained coatings were examined by scanning electron microscope (SEM), atomic force microscope (AFM) and X-ray diffraction (XRD), respectively. With increasing the average current density, morphologes of the coatings changed from those with large and well defined crystal grains obtained at jav of 15 mA cm-2 (the dominant effect of activation control) to fine-grained obtained at jav of 50 mA cm-2 (the mixed activation-diffusion control) and those with globules when diffusion becomes a dominant process (jav = 70 mA cm-2). The minimum roughness showed the Cu coating obtained at jav of 50 mA cm-2 . Simultaneously, crystal structure changed from the strong (220) to the strong (111) preferred orientation with increasing average current density. The change of surface morphology was discussed by the effect of applied parameters of the PC regime on the type of electrodeposition control, while change in crystal orientation of produced coatings was explained by various rates of growth on various crystal planes. Hardness analysis of the produced coatings was performed by application of the Chicot-Lesage (C-L) composite hardness model. By application of this model, the relative indentation depth (RID; where RID = h/d; h is an indentation depth, and d is a thickness of coating) of 0.14 was established as the limiting value separating the area of the absolute hardness of the Cu coatings (RID < 0.14) from the area in which application of the C-L model is necessary for a determination of the absolute hardness of coatings (RID > 0.14). For RID < 0.14, the measured composite hardness corresponded to the absolute hardness of the coating

Effect of concentration pigment particles on microstructure of the metal matrix copper composite coatings

This research focuses on the synthesis and characterization of composite coatings via electrochemical route with co-deposition pigments. For that reason, the effect of adding yellow green phosphorescent pigment on microstructural evaluation of the Cu/pigment composite systems has been investigated.Second International Conference on Electron Microscopy of Nanostructures ELMINA 2022, August 22nd-26th, 2022, Belgrade, Serbia

Одређивање апсолутне тврдоће електролитички добијених превлака бакра применом Chicot-Lesage композитног модела тврдоће

In this study, a novel procedure, based on application of the Chicot–Lesage (C–L) composite hardness model, was proposed for the determination of an absolute hardness of electrolytically produced copper coatings. The Cu coatings were electrodeposited on the Si(111) substrate by the pulsating current (PC) regime with a variation of the following parameters: the pause duration, the current density amplitude and the coating thickness. The topography of produced coatings was characterized by atomic force microscope (AFM), while a hardness of the coatings was examined by Vickers microindentation test. Applying the C–L model, the critical relative indentation depth (RID)c of 0.14 was determined, which is independent of all examined parameters of the PC regime. This RID value separated the area in which the composite hardness of the Cu coating corresponded to its absolute hardness (RID <0.14) from the area in which the application of the C–L model was necessary for a determination of the absolute coating hardness (RID ≥ 0.14). The obtained value was in a good agreement with the value already published in the literature.Предложен je нови поступак заснован на примени Chicot–Lesage (C–L) композитног модела тврдоће за одређивање апсолутне тврдоће електролитички добијених превлака бакра. Превлаке бакра су електрохемијски исталожене на силицијуму (111) оријентације режимом пулсирајуће струје варирањем следећих параметара: трајање паузе, амплитудна густина струје и дебљина превлаке. Топографија произведених превлака је окарактерисана микроскопијом атомских сила, док је тврдоћа превлака испитивана Викерсовим тестом утискивања. Применом C–L композитног модела тврдоће, одређена је критична релативна дубина утискивања (RID), од 0,14, која је независна од свих испитиваних параметара режима пулсирајуће струје. Ова вредност раздваја област у којој композитна тврдоћа превлаке може да се изједначи са њеном апсолутном тврдоћом (RID << 0,14) од области у којој је неопходно применити C–L модел за одређивање апсолутне тврдоће превлаке (RID ≥ 0,14). Добијена вредност RID показује добро слагање са вредностима публикованим у литератури

Influence of intensity of ultrasound on morphology and hardness of copper coatings obtained by electrodeposition

The influence of various intensities of ultrasound applied for the electrolyte stirring on morphological and mechanical characteristics of electrolytically produced copper coatings has been investigated. The copper coatings produced by the galvanostatic regime of the electrodeposition from the basic sulphate electrolyte and the electrolyte with added levelling/brightening additives at the low temperature were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques (surface morphology and topography, respectively) and by Vickers microindentation (hardness). The roughness of coatings increased with the increasing intensity of ultrasound, indicating that morphology of the coatings worsened with the enhanced application of ultrasonic waves. This is attributed to the strong effect of ultrasound on hydrodynamic conditions in the near-electrode layer, which is manifested by the increase of share of the activation control in the mixed activation-diffusion control of electrodeposition with increasing the intensity of ultrasound. The concept of "effective overpotential" originally proposed to explain a change of surface morphology in the conditions of vigorous hydrogen evolution is also applicable for a change of morphology of Cu coatings under the imposed effect of ultrasonic waves. Hardness analysis of the coatings showed that an intensity of applied ultrasound did not have any significant effect on the hardness, especially for the Cu coatings produced from the basic sulphate electrolyte

Morphology, structure and hardness of electrolytically produced copper coatings

Poster presented at: 4th International Congress of Chemists and Chemical Engineers of Bosnia and Herzegovina, June, 30th-July, 02nd, Sarajevo, Bosnia and HerzegovinaAbstract: [https://cer.ihtm.bg.ac.rs/handle/123456789/5213

Optimization of electrodeposition parameters to improve composite hardness of nickel coatings on brass substrate for varying film thicknesses and applied indentation loads

In this investigation, nickel coatings were electrodeposited on brass substrate. The effects of electrodeposition process parameters such as, current density and deposition time (coatings thickness), on surface morphology and composite hardness values were studied. The value of the measured composite hardness by Vickers microindentation technique of the selected “hard film on soft substrate” composite system type depends on the applied indentation loads. For this reason, the microindentation loads are also included in the analysis. According to the experiment plan obtained by Design-Expert software, nickel coating has been produced on the brass cathode using galvanostatic regime (DC) with magnetic stirring of the electrolyte. The nickel sulphamate electrolyte with saccharine additive was used for Ni electrodeposition. Then, response surface methodology (RSM) was used to establish an adequate mathematical model. Subsequently, a mathematical model was developed to weight the effects of each input parameters (coating thickness, current density and indentation load) on the output parameter (composite hardness) of electrodeposited nickel coatings on brass substrate. According to the obtained results, the coating thickness and indentation load greatly influenced resulting composite hardness. On the other hand, coating current density primarily influenced microstructure and surface roughness. The topographic modification of the Ni coating surface depending on the post-treatment (mechanical and chemical) after deposition was studied using AFM microscopy

Application of copper electrodeposition processes in visualization of latent fingerprints obtained on various substrates

In this study, a basic sulfate electrolyte for electrochemical copper deposition and a sulfate electrolyte with additives to improve coating quality were used. It has been shown that for the visualization of latent fingerprints, it is better to use an electrolyte without additives. The use of electrolytes with additives has not been shown to be adequate for these purposes due to the effect of filling fingerprint ridges and reducing contrast

Invasive lobular carcinoma of the breast presenting as retroperitoneal fibrosis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Invasive lobular carcinoma of the breast represents approximately 6.3% of mammary malignancies. Distant metastasis of invasive lobular carcinoma to the peritoneum or retroperitoneum has been reported fairly frequently.</p> <p>Case presentation</p> <p>We report the case of a 59-year-old Caucasian-Canadian woman with invasive lobular carcinoma of the breast presenting with retroperitoneal fibrosis and bilateral ureteral obstruction. Intra-operative pathology consultation did not reveal malignancy. The diagnosis, however, was confirmed on permanent sections by histological appearance in addition to immunohistochemistry. To the best of our knowledge, this is the first reported case of invasive lobular carcinoma of the breast presenting with retroperitoneal fibrosis.</p> <p>Conclusion</p> <p>In a case of unexplained ureteric obstruction and retroperitoneal fibrosis, more comprehensive physical examination and additional ancillary studies may be warranted to rule out malignancy as an underlying etiology. This case also emphasizes that intra-operative frozen section consultation cannot always be fully relied upon to exclude a malignancy as the etiology of retroperitoneal fibrosis. Moreover, in permanent histopathology sections, immunohistochemistry testing can be of value to rule out metastatic disease where the morphology is not salient. There is a need for a thorough physical examination of patients with retroperitoneal fibrosis, including the breast and gynecological organs.</p

Primary myxofibrosarcoma of the parotid: case report

<p>Abstract</p> <p>Background</p> <p>Myxofibrosarcoma is common in the extremities of elderly people and is characterized by a high frequency of local recurrence.</p> <p>Case presentation</p> <p>We report a 37 year old female who presented with a 4-month history of facial pain and a 3-month history of painful progressive swelling in the preauricular area. She underwent a total parotidectomy. The tumor was histopathologically and immunohistochemically diagnosed as a low-grade myxofibrosarcoma. The patient was free of disease 9 months after surgery with uneventful post-operative clinical course.</p> <p>Conclusions</p> <p>Parotid area swelling should always alert doctors. To our knowledge, this is the first case of parotid myxofibrosarcoma. It should be added to the differential diagnosis of diseases of the parotid. We have to recognize this disease and seek adequate treatment for it.</p