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SummaryBackgroundPerforming cardiopulmonary resuscitation (CPR) and postresuscitation care in the intensive care unit (ICU) are standardized procedures; however, there is evidence suggesting sex-dependent differences in clinical management and outcome variables after cardiac arrest (CA).MethodsA prospective analysis of patients who were hospitalized at a medical ICU after CPR between December 2018 and March 2020 was conducted. Exclusion criteria were age 2-tests, for survival analysis both univariate and multivariable Cox regression were fitted.ResultsA total of 106 patients were included and the majority were male (71.7%). No statistically significant difference regarding 6‑month mortality between sexes could be shown (hazard risk, HR 0.68, 95% confidence interval, CI 0.35–1.34;p = 0.27). Neurological outcome was also similar between both groups (CPC 1 88% in both sexes after 6 months;p = 1.000). There were no statistically significant differences regarding general characteristics, pre-existing diseases, as well as the majority of clinical and laboratory parameters or measures performed on the ICU.ConclusionIn a single center CPR database no statistically significant sex-specific differences regarding post-resuscitation care, survival and neurological outcome after 6 months were observed.

Further increasing the conversion efficiency of silicon solar cells by advanced solar cell concepts like SHJ (Silicon Hetero-Junction), PERT (Passivated Emitter Rear Totally diffused), IBC (Interdigitated Back-Contact), requires a highly controlled silicon surface in terms of metal impurity density. The goal of this study is investigating the deposition property of different metals in acidic cleaning solutions and consequently determining the impact of these impurities on the effective minority lifetime of the crystalline silicon solar cell material. The deposition behaviour of impurities is mathematically described with an adsorption isotherm theory. Once attached at the silicon surface, the metal impurity can diffuse into the silicon bulk material during a high temperature process step like diffusion, passivation or contact annealing (firing). First, we have studied the adsorption isotherm behaviour of prominent metal impurities (Fe, Cu, Ti, Co, Cr and Zn) in acidic liquid onto a silicon surface. Moreover, the impact of metal impurities on effective minority carrier lifetime in commercially available n-type Cz-silicon (3–5 Ω cm, 239 cm2) is determined. From controlled contamination experiments we can extract an exchange volume, that provides the minimum amount on wet chemical cleaning solution that is required to clean a silicon surface from a given high metal impurity level to a specified low metal impurity level. This exchange volume plays a crucial role by defining feed and bleed recipes on wet chemical cleaning tanks in solar cell manufacturing. A second parameter extracted is the effective minority carrier lifetime degradation of the metal impurities. After deposition on the surface, the impurities are driven into the silicon bulk by high temperature processes. Depending on the lifetime degradation capacity, a relation of effective minority carrier lifetime versus surface contamination level could be identified for each metal impurity. We found Co, Fe and Cu having a strong impact on effective minority carrier lifetime degradation, e.g. 2e10/cm2 Fe surface concentration can reduce the effective minority carrier lifetime by 75%, while Ti, Zn and Cr are more moderate and only high surface concentrations above 1e12/cm2 lead to effective minority carrier lifetime degradation of more than 20% compared to the non-contaminated wafers.

Background: Heart failure is a pathophysiological state, which is still associated with high morbidity and mortality despite established therapies. Diverse well-known biomarkers fail to assess the variety of individual pathophysiology in the context of heart failure.Methods: An analysis of prospective, multimarker-specific therapeutic approaches to heart failure based on studies in current literature was performed. A total of 159 screened publications in the field of biomarkers in heart failure were hand-selected and found to be eligible for this study by a team of experts.Results: Established biomarkers of the inflammatory axis, matrix remodeling, fibrosis and oxidative stress axis, as well as potential therapeutic interventions were investigated. Interaction with end organs, such as cardio-hepatic, cardio-renal and cardio-gastrointestinal interactions show the complexity of the syndrome and could be of further therapeutic value. MicroRNAs are involved in a wide variety of physiologic and pathophysiologic processes in heart failure and could be useful in diagnostic as well as therapeutic setting.Conclusion: Based on our analysis by a biomarker-driven approach in heart failure therapy, patients could be treated more specifically in long term with a consideration of different aspects of heart failure. New studies evaluating a multimarker – based therapeutic approach could lead in a decrease in the morbidity and mortality of heart failure patients.

Background: Heart failure (HF) remains one of the leading causes of death to date despite extensive research funding. Various studies are conducted every year in an attempt to improve diagnostic accuracy and therapy monitoring. The small cytoplasmic heart-type fatty acid-binding protein (H-FABP) has been studied in a variety of disease entities. Here, we provide a review of the available literature on H-FABP and its possible applications in HF. Methods: Literature research using PubMed Central was conducted. To select possible studies for inclusion, the authors screened all available studies by title and, if suitable, by abstract. Relevant manuscripts were read in full text. Results: In total, 23 studies regarding H-FABP in HF were included in this review. Conclusion: While, algorithms already exist in the area of risk stratification for acute pulmonary embolism, there is still no consensus for the routine use of H-FABP in daily clinical practice in HF. At present, the strongest evidence exists for risk evaluation of adverse cardiac events. Other future applications of H-FABP may include early detection of ischemia, worsening of renal failure, and long-term treatment planning.

Trace metal impurities are known to severely degrade the performance of silicon solar cells. The effect of Nickel dissolved in dilute cleaning solutions was studied in detail. Clean wafers were exposed to these mixtures.The resulting surface concentration and the effect on carrier lifetime upon thermal oxidation, were found to correlate with a first order relation to the concentration of Ni in the solution.The removal of Nickel from the surface by different cleaning recipes was evaluated and compared using thermal oxidation followed by carrier lifetime measurements.The resulting surface concentration and the effect on carrier lifetime upon thermal oxidation, were found to correlate with a first order relation to the concentration of Nickel in the solution.

In this work we present bifacial cells with Ni/Ag co-plated contacts with average V oc values of 691±2 mV and efficiencies of 22.4±0.2 % (internal measurement using a lowly-reflective Gridtouch TM contacting unit from Pasan). The Ni/Ag co-plating sequence used in this paper presents numerous advantages, most notably: non-contact batch processing and cell metallization costs potentially below 7 $ct./cell. In the first part of this paper, two different emitter passivation schemes are compared (SiO 2 /SiN x and Al 2 O 3 /SiN x ) and we demonstrate that Al 2 O 3 /SiN x enables a ~17mV gain in V oc and ~0.3 mA/cm 2 gain in j sc thanks to reduced recombination losses. In the second part of this paper, proof-of-concept glass/backsheet and glass/glass 1-cell laminates are fabricated using multi-wires interconnection and light I-V results are presented. Finally, we demonstrate that one of the first 1-cell glass/backsheet laminates with Ni/Ag co-plated contacts and multi-wires interconnection currently experiences less than 4% abs. loss in maximum power after 400 thermal cycles (-40 to +85°C).

Manufacturing of semiconductor integrated circuits has become a major industry producing a lot of key component for “commodity products”. As such it obeys the trends of all economic activities. One of the key trend is increasing learning with increasing accumulated business volume. A trend that goes a long is reduction of manufacturing cost (per function or performance) and market value. In the past this trend was accomplished by continuous scaling down the feature size of the transistor, the key component of a chip. This has led to a boost in productivity as the numbers of chips on a wafer increased, while manufacturing cost per wafer, barely went up. At the same time the transistors and circuits gained in performance (such as speed, power consumption etc…). Several cycles of feature size reduction (“geometric scaling down”) followed at a high pace. In this technology race, the focus was on technology enablement, rather than on reducing the wafer manufacturing cost. Currently the traditional approach of reduction of cost/function by geometric scaling seems to run out of steam and slow down significantly. The goal of this work is to study a simple processing configuration to create a better understanding of wet processing in order to make it more cost effective. The system of choice is a simple parallel flow of liquid along the wafer surface. In order to have a good uniformity the transport of species should be relatively fast as to not be a limiting factor for the overall process. The goal is to minimize equipment cost by the use of very simple hardware and rather short process times (order of 10 sec). Also the consumption of chemicals will be limited by using a narrow tank with minimal volume and by extended use and re-circulation of chemicals until they are “completely” exhausted. Where appropriate (in view of the total process time, and contamination loading) a cascade sequence of reactors and “cross-flow” of chemicals would be applied. In a first approximation the parallel-plate flow pattern is assumed to be laminar with a parabolic (Poiseuille) velocity profile. Near the wafer surface this velocity profile is approximately linear (eq. (1)). The mass transport of chemicals is initially by convection flow parallel to the x direction and eventually to the wafer surface by diffusion along the y-direction. The position along the x-axis where the diffusion transport can marginally keep up with the convection transport is L (eq. 2). Ideally, fast diffusion is obtained if this point is positioned beyond the edge of the wafer. (by using a high liquid flow rate, or allowing sufficient process time.) Equation (2) allows to determine an optimal flow rate for a desired total process time. In order to evaluate the concept a simple narrow single wafer reactor was built. The total width of the reactor can be modified to 2, 4, or 10 mm. The reactor can be supplied with rinse water in a recirculation mode or in a flow direct to drain at a flow rate up to 30 lpm. Dye-imaging tests were performed to analyse the flow behavior. Methylene Blue (Sigma Aldrich) was injected into the flow through a narrow injection needle. These tests confirmed the flow to be laminar for a flow rate of 10 lpm (Re= 560). The experimental concept tank is connected to a (pump + canister) recirculation system to allow for a high flow without high consumption rate of chemicals. The tank can be filled with (MKS) ozonated UPW or with aqueous HF-mixtures. This allows for performing an “imec cleaning” sequence. For cost reasons, this prototype reactor is made out of low basic transparent polymers for optimal viewing, but with sacrificing chemical compatibility. The cleaning chemicals are recirculated at 10 l/min. Good metal (Fe) removal efficiency is demonstrated with carrier lifetime (as high as 0.5 ms) measurements on n-type silicon. Figure 1

We have studied the effect of different cleanings at device level for nPERT (passivated Emitter, Rear Totally diffused) cells with a rear epitaxial emitter. Cleanings based on sulfuric acid and peroxide mixtures (SPM), which are effective but also expensive, were used as reference. We found that simplified cleanings such as those based on sulfuric acid and ozone mixtures (SOM), and those based on water and ozone (IPV), are giving similar results at device level as the expensive SPM cleaning, leading to similar J0e, J0, FSF, and lifetime values. The implied VOC values of corresponding test devices fabricated using the simplified cleanings are at the same high level as the test devices using more expensive SPM cleanings. Actual nPERT devices with moderately doped epitaxially-grown emitters with a constant doping profile (box profile) showed average efficiencies above 22.0% for both SOM and IPV cleanings. Very high VOC values of up to 695 mV and implied VOC values of up to 730 mV were shown for cells with a flat rear surface. Finally, the best nPERT cells with rear epitaxial emitter and SOM cleaning showed efficiencies up to 22.5%, as externally confirmed by ISE CalLab.

Advanced concepts for photovoltaic silicon solar cells, especially high-efficiency n-type solar cells, requires appropriate wet cleaning treatment in order to remove metallic contamination prior to high temperature processes like diffusion and passivation [1]. The cost of the cleaning process should be as low as possible that requires an optimized usage of the chemicals by increasing process tank lifetimes and developing dedicated feed and bleed recipes. The just clean enough concept has been developed to fulfil the needs of PV industry to minimize the consumption of chemicals. When the dominant contamination metal is identified in quality and quantity, a dedicated wet chemical cleaning process can be applied to remove the metal concentration from the semiconductor surface under a specified limit with the minimum volume on cleaning solution. The paper describes how to optimize a dedicated wet cleaning process for prominent metal impurities like Fe, Cu, Cr, Ti, Co and Zn. For each metal an exchange volume is determined to develop a feed and bleed recipe. The accumulation of the metal impurities in the process tank is calculated and process tank lifetimes are predicted.

Contamination of silicon semiconductor cells strongly influences their working properties, such as minority carrier lifetime. During manufacture, i.e. cutting off the silicon ingot, the entry of metal contaminants into the silicon needs to be avoided since it decreases the performance of solar cells. To study this effect, controlled contaminations were performed by immersing silicon wafers in dilute HCl-based (pH = 1.3) solutions, containing precisely defined amounts of metal concentrations of 30, 100, 300, and 1000 ppb. The two most common and most damaging transient metals, the iron and copper, were tested. Determination of surface contaminations was carried out by two different methods: Total Reflection X-ray Fluorescence (TXRF) measurements and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). The minority carrier lifetime was checked by photoluminescence (PL) measurements. The LA-ICP-MS method was proved to be an effective arrangement for direct determination of ppb-level surface impurities and their penetration depths. The results received by TXRF and LA-ICP-MS were compared. The advantage of LA-ICP-MS was that in addition to a simple contamination level determination it could be used to acquire the total surface map of contamination.

This work focuses on the fabrication of nPERT(Passivated Emitter, Rear Totally Diffused) devices incorporating an epitaxially grown single side rear-emitter. Such epi-nPERT cells are fabricated in a simplified way using the selectivity of the epitaxial deposition, which is obtained by a PECVD-SiOxlayer, that not only mask the front but also passivates the cell. The cell performance is studied in terms of: i) various front surface fields (FSF) applied prior to emitter epitaxy and ii) usage of laser doping as an alternative to laser ablation for a front contacting scheme. The results show: i) a clear relationship between the depth of the homogeneous FSF and its impact on the open circuit voltage of the devices, with a shallow FSF having the highest V OC loss due to laser damage and ii) laser doping on devices with a relatively deep diffused FSF giving 8 mV increase in V OC as compared to devices with ablated dielectrics and a V OC increase of almost 30 mV in case a shallow selective FSF is applied. This results in a best efficiency obtained so far for the epi nPERT devices of 21.6% (226 cm 2 ).

Tunneling aluminum oxide (Al2O3) layers are proposed as a candidate for hole collecting passivated contacts. These ultra-thin Al2O3 films ($\approx 1.5\text{nm}$) are deposited on boron diffused ($113\Omega/\square$) hydrophilic surfaces to act as metal-insulator-semiconductor (MIS) contacts. Record values of emitter recombination current densities (35–40 fA/cm2) and contact resistivity ($\approx 15\mathrm{m}\Omega\cdot \text{cm}^{2}$) were measured for this type of contact. Most importantly, all of these processes are carried out using industrially relevant tools on Cz wafers with non-polished surfaces.

Interdigitated back contacted (IBC) silicon solar cells have long been shown as high conversion efficiency solar cells, with values as high as 25.0% reported by Sunpower [1]. Such high efficiencies are enabled by the cell structure, with the absence of front side metal shading, which can then be optimised from optical and passivation perspectives. High bulk lifetime silicon and a low series resistance metallisation scheme can also enhance the efficiencies. Other advantages include the easier module incorporation given both metal contacts are located on the rear of the cell.

Silicon solar cells are the dominating technology in photovoltaics (PV) industry and have a market share of more than 85% of the modules produced for roof top installations.

The cumulative installed solar power generation has been rising exponentially over the past decade. This has lead to a concomitant rise in production capabilities, leading eventually to excess production capabilities and rapid price declines per unit. In order to compete with the standard electricity generation the cost of solar panel production and installation needs to decrease even further. At the same time the solar panel and cell makers need to be able to keep a healthy margin. A crucial element in this exercise is a close control on the Cost of Ownership (CoO) of a solar cell / panel fabrication site.

We present large-area n-type PERT solar cells featuring a rear boron emitter passivated by a stack of ALD Al2O3 and PECVD SiOx. After illustrating the technological and fundamental advantages of such a device architecture, we show that the Al2O3/SiOx stack employed to passivate the boron emitter is unaffected by the rear metallization processes and can suppress the Shockley-Read-Hall surface recombination current to values below 2 fA/cm2, provided that the Al2O3 thickness is larger than 7 nm. Efficiencies of 21.5% on 156-mm commercial-grade Cz-Si substrates are demonstrated in this study, when the rear Al2O3/SiOx passivation is applied in combination with a homogeneous front-surface field (FSF). The passivation stack developed herein can sustain cell efficiencies in excess of 22% and Voc above 685 mV when a selective FSF is implemented, despite the absence of passivated contacts. Finally, we demonstrate that such cells do not suffer from light-induced degradation.