Conventional Cleaning Research Articles

Design and implementation of waste cleaning automation system for the shrimp pond bottom

In intensive shrimp cultivation system, residual waste that settled at the bottom of the pond is impacting water quality. Therefore, there is a need to regularly clean this residual to maintain the water quality in good condition. In this paper we describe the automatic instrument system to clean up the bottom of the pond. This waste cleaning instrument uses the principle of equilibrium between the main component in the form of a pyramid and supporting components, namely the water container. The pyramid has a dimension of 2x2x1.3m and 4 poles that serve as rails and support for pulleys that hang both components. The framework of the pyramid is made of pipes and then the frame is coated with HDPE sheets and solar flat. The pyramid will go up and down in accordance with the water container, if it is filled with water and empty automatically because it is installed two submersible pumps to drain and fill the water container. From the field test results it was found that this instrument works effectively, where in one cleaning, it can be done in less than 5 minutes compared to conventional cleaning which takes hours.

Tradeoff Between Area Coverage and Energy Usage of a Self-Reconfigurable Floor Cleaning Robot Based on User Preference

Floor cleaning robots have been developed to cope with the issues arisen with conventional cleaning methods that involve extensive human labor. hTetro is a self-reconfigurable floor cleaning robot that has been introduced to improve area coverage. Polyomino tiling theory is utilized by hTetro to plan area coverage. Energy usage and area coverage are distinct for different tiling arrangements, and they are often conflicting entities. Therefore, hTetro needs to maintain the tradeoff between area coverage and energy usage to improve its performance. This paper proposes a novel method to determine the tradeoff between area coverage and energy usage of a tiling theory-based self-reconfigurable floor cleaning robot per user preference. A linguistic option such as “High coverage” that represents user preference has uncertainty since fuzzy linguistic terms do not possess definitive meaning. Moreover, the meaning of such user preference depends on the present status of the robot. Thereby, a novel fuzzy inference system is proposed to determine the tradeoff between area coverage and energy usage by interpreting the meaning of user preference while accounting for the present status of the robot. A Weighted Sum Model (WSM) based Multiple-criteria decision-making (MCDM) method is adapted per user preference interpreted by the fuzzy inference system. The behavior of the proposed system has been evaluated considering heterogeneous test cases. The behavior of the test cases confirms the applicability of the proposed concept for adapting the tradeoff between area coverage and energy usage of a self-reconfigurable floor cleaning robot based on user preference.

Removal of Contaminant Nanoparticles with $$\hbox {CO}_2$$ Nanobullets at Atmospheric Conditions

As the feature size of semiconductor chips is decreasing down to nanometric scales, cleaning of nanoscale contaminant particles without damaging the fine features puts forth severe technological challenges. Here we introduce a design methodology of a nozzle to generate a beam of supersonic $$\hbox {CO}_2$$ solid nanobullets into the air at atmospheric pressure, which dislodge the contaminant particles by colliding with them. The dry cleaning scheme proposed here does not resort to the chillers, vacuum chamber, and carrier-gas handling system, which conventional dry cleaning systems often required and thus hampered their practical applications. We provide a theoretical framework to select key design parameters, such as the area ratio of the nozzle throat and exit and the supply gas pressure. We experimentally verify the superior capability of our nozzle in generating a $$\hbox {CO}_2$$ aerosol beam under the atmospheric back pressure condition. Additional process parameters including the stand-off distance and the incident angle of the $$\hbox {CO}_2$$ beam are optimized to maximize the cleaning efficiency and minimize the pattern damages. Our work suggests a practical nanoparticle cleaning scheme that is faster and simpler than the conventional dry cleaning methods.

Green Cleaning for the Sri Lankan Healthcare Sector: Critical Support Factors and Barriers

The extensive use of cleaning chemicals and disinfectants in the healthcare industry in recent years has raised concerns over the effectiveness of conventional cleaning in creating safe and healthy environments. Green cleaning was introduced in the 1980s as a substitute for conventional cleaning. Green cleaning denotes methods and products of cleaning, which incorporate environmentally friendly ingredients that preserve human health and environmental quality. Even though there is a rapid adoption of green cleaning in many countries, Sri Lanka seems to fall behind in shifting to green cleaning. This research focuses on investigating the factors that either support or obstruct green cleaning in Sri Lanka. A qualitative research involving interviews of experts were conducted among cleaning related managerial personals and the data was analyzed through content analysis. The paper concludes that the most notable support factors were proper awareness, training and education, top management commitment and availability of green cleaning legislation and guidelines. The barriers were lack of awareness of the stakeholders, lack of top management commitment, lack of technical advancement in the country and lack of government support.

Novel H2O2–MnO2 system for efficient physico-chemical cleaning of fouled ultrafiltration membranes by simultaneous generation of reactive free radicals and oxygen

The novel H2O2–MnO2 system was developed to achieve highly efficient membrane cleaning for both fouled PVDF and PES membranes in this study. Compared with conventional chemical cleaning process in which the whole membrane module had to be soaked in highly concentrated solution of chemical reagent for long period of time, the H2O2–MnO2 cleaning process conducting for only 5 min in 0.5 wt% H2O2 solution could achieve more than 95% recovery of permeate flux and almost total removal of the irreversible foulants. More importantly, the permeate flux and filtration efficiency of the membrane could be still kept stable after 6 runs of consecutive fouling and cleaning. Based on the systematic microscopic analyses, Electron Spin Resonance (ESR), Fourier Transform Infrared Spectroscopy (FTIR), as well as the quenching experiments with different free radical scavengers, the outstanding performance of H2O2–MnO2 system was attributed to the generation of both free radicals and abundant oxygen simultaneously, leading to the physico-chemical membrane cleaning. Conclusively, the newly developed H2O2–MnO2 system demonstrated noteworthy advantages on efficient membrane cleaning, and exhibited highly potential for the wide application in practical water treatment process.

A new air-washing method to clean fabric filters clogged with submicron fume particles: A pilot-scale study

This study investigates a new air-washing cleaning system that directly injects compressed air on the filter surface for filter regeneration in a fabric filter (FF) dust collector. A pilot-scale FF is designed to test the new system and to compare it with the conventional pulse-jet cleaning system with regard to filter clogging by fume particles. A pleated filter with a filtration area of 2.4 m2 is installed in the FF and a thermal steel spraying gun is used to supply the fume particles. Pressure drop and particle emission concentration are monitored to examine the effect of the new system on filter regeneration and collection efficiency. The results show that the air-washing cleaning is effective for filter regeneration, as it allows the FF to operate stably for a long time, whereas the pulse-jet cleaning fails to achieve filter regeneration, resulting in a continuously increasing pressure drop. In addition, air-washing cleaning shows better performance on collection efficiency than the pulse-jet cleaning method, as it reduces the outlet particulate matter concentration to less than half that of the pulse-jet cleaning.

Wet Cleaning by Using Amphoteric Electrolyzed Water for Mask Cleaning

Process achievement for manufacturing extreme ultraviolet(EUV) semiconductor device requires profound technical varieties such as extreme extension of the existing concepts or new evolutional ones. In this study, a new technology was proposed to fulfill technical details required for EUV semiconductor device cleaning and manufacturing. The special electrolysis technology of ultrapure water(UPW) was introduced to generate water possessing quite unexpectedly mixed character such as pH of 6.5 to 6.7 and oxidation reduction potential(ORP) of -540 to –560 mV at room temperature. Since ORP of –550 mV lasted for several days, it was postulated that water clustering reaction due to hydrogen bond could hinder or retard recombination of H+ and OH- ions by synchronously isolating them electronically and physically. This amphoteric water was applied to cleaning process of EUV device manufacturing to carry out the experiment requiring eventually no chemical use for wet cleaning because of 10 nm feature size. Some results were so excellent that it was convinced that this water clean was evolutional to meet EUV requirements. This water did eliminate adsorbed leftovers of previous chemical treatments and minimized surface modifications because of non-chemical character so that it did not provide any chance of haze formation. Since particle removal efficiency(PRE) was very high, it was proposed that there might be other cleaning mechanism than double layer repulsion(DLR) of colloids. Conclusively, it is time to review the conventional wet cleaning technology and to adopt new concept of the amphoteric water to realize the cleaning technology of EUV device era.

The Adhesion and Removal Mechanism of Ceria Particles for STI Post-CMP Cleaning Process

Chemical mechanical planarization (CMP) is an essential step to remove overburden oxide surface and form STI (Shallow Trench Isolation) structures during the semiconductor manufacturing. This is usually carried out with ceria slurry due to high selectivity between oxide and nitride surfaces. However, strong ceria adhesion to oxide surface is a major concern, as it cannot be removed easily during the post-CMP cleaning step. Generally, it is performed by a combination of physical and chemical cleaning. Conventional cleaning solutions such as DHF (Dilute Hydrogen Fluoride), SC1(NH4OH: H2O2: H2O mixture), SPM (H2SO4:H2O2 mixture) solutions are used with optimized concentrations and sequences with the support of physical forces such as PVA brush scrubbing or megasonic. However, the adhesion and removal mechanism of ceria particles from the oxide surface is not clear yet. The ceria particles would attach to the oxide to the surface may be due to electrostatic interaction or valence (Ce3+/Ce4+) effect or chemical bonding linkage of Ce-O-Si. These interactions are strongly affected and changed based on the pH of ceria used for polishing. In this work, it was emphasized to identify the specific individual mechanisms of physical cleaning and chemical cleaning in removing ceria particles from the oxide surface. Two types of physical cleanings, one is the non-contact mode (megasonic) cleaning and another one is contact mode (PVA brush) cleaning, were performed. The effect of different chemicals on removing the ceria particles was also performed. The key mechanism for the ceria particle cleaning was hypothesized. TEOS coupons (4´4 cm) were polished with ceria slurry (100nm) of pH 4 and 8, containing no additives. The optimization of physical cleaning experiments, performed with only DIW, was carried out with a single wafer megasonic cleaning (Akrion, 0.83MHz) and brush cleaning tool (lab designed pin type brush). Chemical cleaning was performed with various chemistries (SC1, DHF, SPM) to compare and understand the ceria removal performance from the oxide surface. The particles before and after cleaning were observed by FESEM and optical microscopy. To understand chemical interactions, the polished samples were analyzed for XPS, ATR FTIR, and Raman analysis before and after cleaning. The type of chemical interactions before cleaning and their modifications with the type of chemistry used were discussed. The comparative study of physical cleaning (megasonic vs. brush) were performed for the removal of ceria particles attached to the surface after polishing with slurries of pH 4 and 8. It was observed that the polished oxide surface was more contaminated with ceria in the pH 8 than in pH 4. Megasonic cleaning was able to remove partially, whereas brush scrubbing removed completely for pH 4 samples. However, the ceria particles from pH 8 samples were strongly attached not removed by megasonic and partially removed by brush cleanings. It could be expected that particles would attach electrostatically at pH 4, whereas chemically through Ce-O-Si bond at pH 8. It may be necessary to use chemical forces to break the chemical bonds between ceria-silica. It was suspected that the change of valence of ceria before and after cleaning with cleaning chemistries also would play a key role. Hence different chemistries were used to check the removability of ceria. The samples before and after cleaning were analyzed with different techniques to understand the chemical forces required to break the ceria-silica bonding. Detailed hypothesis for the ceria removal was explained by their chemical interactions with different chemistries.

Atomic layer deposition growth of SnS2 films on diluted buffered oxide etchant solution-treated substrate

In this report, two types of substrates were prepared for deposition of few-layer tin disulfide (SnS2) via atomic layer deposition (ALD). The first substrate was prepared using a conventional cleaning method, while the second substrate was rinsed with buffered oxide etcher (BOE) solution after conventional cleaning. Changes in the substrate were confirmed by X-ray photoelectron spectroscopy, contact angle measurements, and electron spin resonance. Characteristics of the SnS2 thin films were determined by X-ray diffraction, Raman analysis, Fourier transform-infrared spectroscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. To investigate growth rate, thickness was measured as a function of ALD cycle number by atomic force microscopy, and 2D layered structure was confirmed by transmission electron microscopy. Findings confirmed that surface treatment using BOE solution was related to an increased growth rate during the initial ALD process. Finally, back-gate field effect transistors based on ALD-grown SnS2 film prepared on substrate that received diluted-BOE surface treatment showed marginal improvement in current on/off ratio from 2.9 × 105 to 6.5 × 105 and mobility from 0.22 cm2/Vs to 0.31 cm2/Vs compared to ALD-grown SnS2 film prepared on bare substrate.

Membrane backwash cleaning using CO2 nucleation

Low pressure membranes, such as ultrafiltration (UF), are widely used in water treatment applications, including the pretreatment of reverse osmosis desalination. UF membranes produce a water of superior quality, in addition to reducing the footprint and the use of chemicals, compared to conventional methods. However, membrane fouling remains a major drawback, and frequent membrane cleanings are required to maintain the flux of water and its quality. Typically, after a series of backwashes using an UF permeate, a chemical cleaning process is applied to fully recover the membrane's permeability. However, frequent chemical cleanings negatively affect the lifetime of the membrane, the environment, and increase operational costs. Here, we introduce a novel cleaning method that uses a solution saturated with CO2 to clean the membranes through the backwash step. As the pressure drops, the CO2 solution becomes supersaturated, and bubbles start to nucleate within the membrane pores and on its surface, resulting in the effective removal of the deposited fouling material. These foulants are further helping the nucleation process as they are considered as imperfection sites with high creation and growth of bubbles. Investigations performed for different synthetic feed solutions of organic compounds (sodium alginate), colloidal matter (silica) and sea salts, at different concentrations, show that our new physical cleaning process using CO2 is more performant than the regular backwash using Milli-Q water. We obtain a 100% flux recovery, in a short time, even under severe irreversible fouling conditions. Based on these results, we conclude that replacing water by a solution saturated with CO2 for the backwash cleaning of filtration membranes provides significant benefits to existing cleaning processes, and represent a promising alternative for improving and lowering the frequency of conventional chemical cleaning methods.

Testing of novel net cleaning technologies for finfish aquaculture

To avoid the negative impacts caused by biofouling development, aquaculture nets around the world are periodically cleaned using high-pressure washers. Net cleaning is labour-intense and costly, can damage antifouling coatings on the nets, and pose contamination as well as fish health and welfare risks. To support the environmental sustainability of the growing aquaculture sector, novel net cleaning methods are needed. This study examined low-pressure-, cavitation-, and suction-based cleaning technologies as alternatives to conventional high-pressure cleaning. Using field experiments, cleaning efficacy, cleaning waste generation, and the impact of cleaning on coating integrity and net strength were evaluated. Cavitation and high-pressure cleaning achieved considerably higher cleaning efficacy than low-pressure and suction cleaning. However, a single high-pressure treatment caused up to 53% coating degradation, compared to 2% for cavitation. All technologies produced similar cleaning waste and neither reduced net strength significantly. This study identifies cavitation cleaning as promising technology for biofouling control on aquaculture nets.

Antimicrobial and antifouling polymeric coating mitigates persistence of Pseudomonas aeruginosa biofilm

Food wasted due to food spoilage remains a global challenge to the environmental sustainability and security of food supply. In food manufacturing, post-processing contamination of food can occur due to persistent bacterial biofilms, which can be resistant to conventional cleaning and sanitization. The objective was to characterize the efficacy of a polymeric coating in reducing Pseudomonas aeruginosa biofilm establishment and facilitating its removal. Viable cell density of a 48 h biofilm was reduced by 2.10 log cfu cm−2 on the coated surface, compared to native polypropylene. Confocal laser scanning and electron microscopy indicated reductions in mature biofilm viability and thickness on the coated material. The antifouling coating improved cleanability, with ∼2.5 log cfu cm−2 of viable cells remaining after 105 min cleaning by water at 65 °C, compared to 4.5 log cfu cm−2 remaining on native polypropylene. Such coatings may reduce the persistence of biofilms in food processing environments, in support of reducing food spoilage and waste

Effect of Photodynamic Therapy, Er,Cr:YSGG, and Nd:YAG Laser on the Push-Out Bond Strength of Fiber Post to Root Dentin.

Objective: To evaluate the push-out bond strength and modes of failure of fiber post to root dentin by using photodynamic therapy (PDT), Er,Cr:YSGG, Nd:YAG laser, and conventional cleaning and shaping (CCS). Materials and methods: Eighty anterior teeth were sectioned in a horizontal manner being 2 mm incisal to the cementoenamel junction, and root canal was prepared for post space. After post space was made, fiber posts were placed inside the root canal system. The fiber posts were subjected to PDT, Er,Cr:YSGG laser, Nd:YAG laser, and conventional cleaning and shaping (CSS) with 20 specimens in each group. Cervical and apical sections were obtained from the specimens. For performing the push-out test, the universal testing machine was used. The formula used for calculating the push-out bond strength was σ = N/mm2. Results: PDT group (8.16 ± 2.19 MPa) achieved the highest mean push-out bond strength, whereas Er,Cr:YSGG (7.24 ± 1.27 MPa) reported the lowest value in the specimens. Among the experimental groups, the ANOVA test expressed statistical difference (p = 0.481). In the cervical segments, the mean push-out bond strength was found to be higher in all of the experimental groups. For the cervical segments, the independent t-test results showed higher mean push-out bond strength values than the apical segments in PDT, Er,Cr:YSGG, Nd:YAG, and CSS groups, respectively (p < 0.05). Twenty failures were observed at the interface level between the adhesive and surface of dentin. Seven failures were found at the interface between mixed and the adhesive and post, respectively. Conclusions: Push-out bond strength to root canal dentin was not affected by PDT, Er,Cr:YSGG, and Nd:YAG laser compared with CCS. However, PDT produced the smallest number of failure modes and slightly higher push-out bond strength to root dentin. Laser treatment using PDT and Er,Cr:YSGG appeared to be clinically efficient showing acceptable push-out bond strength of fiber post with less number of failures at different regions of the root dentin.

Effect of photodynamic therapy and ErCrYSGG laser irradiation on the push-out bond strength between fiber post and root dentin.

To evaluate the push out bond strength and modes of failure of fiber post by using photodynamic therapy (PDT), Er,Cr:YSGG laser and conventional cleaning and shaping (CCS). Sixty maxillary anterior teeth were sectioned horizontaly 2 mm incisal to the cemento-enamel junction, and root canal were prepared for post space. Tapered fiber posts were placed inside the root canal after post space was made. The fiber posts were subjected to PDT, Er,Cr:YSGG laser and CSS with 20 specimens in each group. The specimens obtained were sectioned in cervical and apical sections. A universal testing machine was used to perform the push out test and the push out bond strength was formulated by σ = C/A, expressed in mega-pascals (MPa). The highest mean push out bond strength was achieved by PDT group (8.08 ± 2.73 MPa) and the lowest was shown by specimens in CCS group (7.45 ± 1.04 MPa). ANOVA showed no statistical difference among the experimental groups (p = 0.481). In the cervical segments, the mean push-out bond strength was found to be slightly higher for all three groups compared to apical segments (P < 0.05). The independent t-tests results showed that the mean push-out bond strength values of the cervical segments were slightly higher than the apical segments in PDT, Er,Cr:YSGG and CSS groups (P < 0.05). Significant differences were observed when mean push-out bond strengths were compared for both cervical (p = 0.037) and apical (p = 0.019) segments between all the groups. Twenty-one failures were found at the interface between the adhesive and the dentin surface, 6 failures were observed at the interface between the adhesive and post, whereas 5 failures were mixed. Push-out bond strength to root canal dentin were not affected by Er,Cr:YSGG compared with conventional cleaning and shaping. However, PDT produced the smallest number of failure modes and slightly higher push-out bond strength to root dentin.

Impact of a probiotic-based hospital sanitation on antimicrobial resistance and HAI-associated antimicrobial consumption and costs: a multicenter study.

PurposeAntimicrobial resistance (AMR) is one of the major threats to human health, and the high frequency of resistant pathogens in the hospital environment can contribute to the transmission of difficult-to-treat health care-associated infections (HAIs). We recently reported that, compared with conventional chemical cleaning, the use of a microbial-based sanitation strategy (Probiotic Cleaning Hygiene System [PCHS]) was associated with remodulation of hospital microbiota and reduction of HAI incidence. Here, we aimed to analyze the impact of PCHS on AMR and related effects, such as HAI-associated antimicrobial drug consumption and costs.Patients and methodsFive Italian hospitals, enrolled in a multicenter study where conventional sanitation methods were replaced with PCHS, were included in the analysis. The study period included a 6-month observation for each sanitation type. Surface microbiota AMR was analyzed using microarray, nested PCR, antibiogram, and microdilution tests. Drug consumption data and related costs were obtained from the medical records of all hospitalized patients affected by HAIs.ResultsPCHS use was associated with up to 99% decrease of the AMR genes harbored by surface hospital microbiota, independently of the resistance types originally present in each individual setting (Pc<0.01). Functional assays confirmed the molecular data, demonstrating a 33%–100% decrease of resistant strains depending on the antibiotic type. Antimicrobial drug consumption associated with HAI onset showed a global 60.3% decrease, with a 75.4% decrease of the associated costs.ConclusionThe spread of AMR in the hospital environment can be limited by the use of sanitation methods to remodulate the hospital microbiota, leading to lower antimicrobial consumption and costs. This approach might be considered as part of broader infection prevention and control strategies.

Wet treatment of 19th century albumen photographs with Gellan gum hydrogel: A comparison to water treatment

Abstract In the conservation practice of albumen photographs, wet cleaning techniques were long used to remove pollutions, gluing components, cellulose degradation products, and to reduce highlight yellowing. However, water immersion, as well as surface cleaning, enhances the cracking of the albumen layer surface. These cleaning methods are suitable for paper artworks. Whereas the conventional water treatment may cause irreversible damage of the paper structure, the use of rigid hydrogel of Gellan gum had been proposed as an alternative technique that is less destructive to the paper structure. Two wet treatments, water and Gellan gum hydrogel, were applied to the samples of original 19th century albumen photoprints. Their effect was assessed using instrumental methods, such as Fourier transform infrared spectroscopy, laser confocal microscopy, scanning electron microscopy, atomic force microscopy, and pH measurements. The effect of wet treatments on the albumen photograph surface cracking was quantified. Despite that Gellan hydrogel is very gentle and efficient tool for the restoration of paper artworks, it is as harmful for the albumen photographs surface as the conventional water surface cleaning, and therefore may be applied on the verso of the photographs solely.

Experimental study of effectiveness of robotic cleaning for fish-processing plants

This paper presents the development and experimental testing of the effectiveness of a robotic cleaning system for fish processing plants. The processing of fish introduces a substantial risk of bacterial contamination, which can cause the spoilage of fish and pose a threat to consumers’ health. Good operational hygiene and precautions, in addition to regular cleaning of the processing plants, are necessary for the reduction of the risk of contamination. The state-of-the art cleaning techniques currently include manual cleaning operations of fish processing plants. The experiments of robotic cleaning presented in this paper were performed in two rounds. First, a test using a conventional low-cost industrial robot mounted on a vertical linear axis was used. As the results from this test seemed promising, a second robotic system was built aiming at a more industrialized version. This system consisted of a serial manipulator, tailored for the task, mounted on a horizontal transportation system, and a comparison was conducted between the cleaning performed by human operators and that performed by the robotic system. An electrical stunner with a connected conveyor belt, which is a typical installation for salmon processing plants, was experimentally inoculated with a cocktail of fish-spoilage bacteria that were allowed to develop a biofilm. Back-to-back cleaning trials with biofilms of Pseudomonas fluorescens, Pseudomonas putida, and Photobacterium phosphoreum confirmed that the industrialized robotic prototype performed equally well or better than the conventional manual cleaning procedure currently used in the industry. The results demonstrate that a robotic system can deliver satisfactory results in the cleaning of fish processing plants, thereby minimizing the potential for the spread of contamination. The proposed robotic concept allows for an automated cleaning system, reduced human labor, increased profitability for the industry, and better stability of the cleaning process.

Study on regeneration of spent hydrochloric acid in chemical coal leaching process

For Indian coals, chemical leaching process has better advantage over the conventional physical cleaning techniques due to its drift origin. Coal leaching is a two-stage process where alkali and acid leaching cycles are used, where most of the ash constituents are accumulated in the spent acid and hence purification of spent acid containing silica, alumina, iron, calcium and magnesium is of great importance. Four different methods namely adsorption using activated carbon, ion exchange with anion exchange resin, pyrohydrolysis and stage-wise neutralisation are studied. Results with adsorption and ion exchange techniques are poor and a maximum of 50% removal is observed. Results indicate that, pyrohydrolysis shows better performance with > 99% pure hydrochloric acid as product but it is energy intensive. Stage-wise neutralisation technique is promising for dilute acid, where silica is precipitated by digestion and it produces magnesium oxide and calcium salt with 86.7% and 93.86% purity respectively.

Atmospheric pressure plasma needle jet treated on aluminium thin film for semiconductor industries

Atmospheric pressure plasma jet has been explored for pre-treatment applications especially in replacing the conventional vacuum plasma cleaning in semiconductor industries. The pre-treatment of plasma is needed to reduce or eliminate adventitious surface contamination on the thin film. This paper shows that the atmospheric pressure plasma jet treatment is highly effective in activating the surface of aluminium (Al) thin film. The image of Al thin film surface topography shows that the treated surface roughness was reduced however the grain size of the particles was unchanged. The XRD pattern of treated Al thin film also remained the same as before of the atmospheric pressure plasma jet treatment. This shows that the atmospheric pressure plasma jet introduce activation layer on the thin film surface without given impact to the thin film crystality.

Termografija u kontroli efikasnosti i bezbednosti laserskog čišćenja

Innovative laser cleaning technology for various surfaces in the industry, includes an integrated approach to controlling the process of laser-material interaction and testing laser treatment results. Laser cleaning has significant advantages over conventional cleaning methods: it has high selectivity, precision, efficiency and reliability in an application for different types of materials. The thermal nature of the laser cleaning process brings a certain risk for cleaning objects, and the process optimization research is in the focus of interest of a large number of scientists. This paper presents the results of laser paint, on the copper surface, and the protective layer, on the printed circuit board, cleaning. The control of the real-time laser cleaning process was carried out using an infrared camera. The micromorphological characteristics of the cleaned surface were examined by optical microscopy.