Plasma FIB Research Articles

Low Energy 500 eV Focused Argon Ion Beam Provided by Multi-Ions Species Plasma FIB for Material Science Sample Preparations

Low Energy 500 eV Focused Argon Ion Beam Provided by Multi-Ions Species Plasma FIB for Material Science Sample Preparations

Reactive oxygen FIB spin milling enables correlative workflow for 3D super-resolution light microscopy and serial FIB/SEM of cultured cells

Correlative light and electron microscopy (CLEM) is a powerful tool for defining the ultrastructural context of molecularly-labeled biological specimens, particularly when superresolution fluorescence microscopy (SRM) is used for CLEM. Current CLEM, however, is limited by the stark differences in sample preparation requirements between the two modalities. For CLEM using SRM, the small region of interest (ROI) of either or both modalities also leads to low success rate and imaging throughput. To overcome these limitations, here we present a CLEM workflow based on a novel focused ion beam/scanning electron microscope (FIB/SEM) compatible with common SRM for imaging biological specimen with ultrahigh 3D resolution and improved imaging throughput. By using a reactive oxygen source in a plasma FIB (PFIB) and a rotating sample stage, the novel FIB/SEM was able to achieve several hundreds of micrometer large area 3D analysis of resin embedded cells through a process named oxygen serial spin mill (OSSM). Compared with current FIB mechanisms, OSSM offers gentle erosion, highly consistent slice thickness, reduced charging during SEM imaging, and improved SEM contrast without increasing the dose of post-staining and fixation. These characteristics of OSSM-SEM allowed us to pair it with interferometric photoactivated localization microscopy (iPALM), a recent SRM technique that affords 10–20 nm isotropic spatial resolution on hydrated samples, for 3D CLEM imaging. We demonstrate a CLEM workflow generalizable to using other SRM strategies using mitochondria in human osteosarcoma (U2OS) cells as a model system, where immunostained TOM20, a marker for the mitochondrial outer membrane, was used for iPALM. Owing to the large scan area of OSSM-SEM, it is now possible to select as many FOVs as needed for iPALM and conveniently re-locate them in EM, this improving the imaging throughput. The significantly reduced dose of post-fixation also helped to better preserve the sample ultrastructures as evidenced by the excellent 3D registration between OSSM-SEM and iPALM images and by the accurate localization of TOM20 (by iPALM) to the peripheries of mitochondria (by OSSM-SEM). These advantages make OSSM-SEM an ideal modality for CLEM applications. As OSSM-SEM is still in development, we also discuss some of the remaining issues and the implications to biological imaging with SEM alone or with CLEM.

A multi-ion plasma FIB study: Determining ion implantation depths of Xe, N, O and Ar in tungsten via atom probe tomography

In this study atom probe tomography was used to determine the implantation depth of four different plasma FIB ion species – xenon, argon, nitrogen, and oxygen – implanted at different acceleration voltages. It was found that lowering the beam energy reduces the implantation depth, but significant implantation was still observed for N, O and Ar at beam energies as low as 2 kV. Furthermore, nitrides and oxides were observed that were formed when using N and O. Xe had the lowest implantation depth compared to Ar, N and O when using the same conditions. No Xe ions were detected in the sample prepared at 2 kV. Experimentally-determined implantation depths were compared to calculated implantation depths. The experiments exhibited deeper-than-predicted ion implantation into the microstructure, but lower-than-predicted ion concentrations.

Plasma fibrinogen acts as a predictive factor for pathological complete response to neoadjuvant chemotherapy in breast cancer: a retrospective study of 1004 Chinese breast cancer patients

BackgroundThe aim of this study was to evaluate the relationship between pre-treatment plasma fibrinogen (Fib) level and pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) in breast cancer patients and to assess the role of plasma Fib as a predictive factor.MethodsData from 1004 consecutive patients with invasive breast cancer who received NAC and subsequent surgery were retrospectively analysed. Both univariate and multivariate analyses based on logistic regression model were performed to identify clinicopathological factors associated with pCR to NAC. Cox regression model was used to determine the correlation between clinical or pathological parameters and recurrence-free survival (RFS). The Kaplan-Meier method and the log-rank test were applied in the survival analysis.ResultsThe median value of Fib, rather than other plasma coagulation parameters, was significantly increased in non-pCR patients compared with pCR patients (P = 0.002). Based on the cut-off value estimated by the receiver operating characteristic (ROC) curve analysis, patients were divided into low or high Fib groups (Fib < 3.435 g/L or ≥ 3.435 g/L). Low Fib levels were significantly associated with premenopausal or perimenopausal status (P < 0.001), tumour size ≤5 cm (P = 0.002), and positive hormone receptor status (P = 0.002). After adjusted for other clinicopathological factors in the multivariate logistic regression model, low Fib status was strongly associated with pCR to NAC (OR = 3.038, 95% CI 1.667–5.537, P < 0.001). Survival analysis showed that patients with low Fib levels exhibited better 3-year RFS compared with patients with high Fib levels in the tumour size>5 cm group (77.5% vs 58.4%, log-rank, P = 0.0168).ConclusionsThis study demonstrates that low pre-treatment plasma Fib (Fib < 3.435 g/L) is an independent predictive factor for pCR to NAC in breast cancer patients. Moreover, T3-featured breast cancer patients with lower Fib level exhibit better RFS outcomes after NAC compared with high Fib status.

Correlative Imaging of Phase Separation in Fe2TiO4 Thin Films Prepared by Conventional Ga and Xe Plasma FIB Processing

Journal Article Correlative Imaging of Phase Separation in Fe2TiO4 Thin Films Prepared by Conventional Ga and Xe Plasma FIB Processing Get access Steven Spurgeon, Steven Spurgeon Pacific Northwest National Laboratory, Richland, Washington, United States Search for other works by this author on: Oxford Academic Google Scholar Bethany Matthews, Bethany Matthews Pacific Northwest National Laboratory, Richland, Washington, United States Search for other works by this author on: Oxford Academic Google Scholar Ron Kelley, Ron Kelley Thermo Fisher Scientific, Hillsboro, Oregon, United States Search for other works by this author on: Oxford Academic Google Scholar Tiffany Kaspar, Tiffany Kaspar Pacific Northwest National Laboratory, Richland, Washington, United States Search for other works by this author on: Oxford Academic Google Scholar Scott Chambers Scott Chambers Pacific Northwest National Laboratory, Richland, Washington, United States Search for other works by this author on: Oxford Academic Google Scholar Microscopy and Microanalysis, Volume 26, Issue S2, 1 August 2020, Pages 186–187, https://doi.org/10.1017/S1431927620013720 Published: 01 August 2020

A New Generation Plasma FIB Column with Higher Probe Current and Improved Imaging Resolution

Journal Article A New Generation Plasma FIB Column with Higher Probe Current and Improved Imaging Resolution Get access Tomáš Hrnčíř, Tomáš Hrnčíř TESCAN Brno s.r.o, Brno, Jihomoravsky kraj, Czech Republic Search for other works by this author on: Oxford Academic Google Scholar Dušan Nešpor, Dušan Nešpor TESCAN Brno s.r.o, Brno, Jihomoravsky kraj, Czech Republic Search for other works by this author on: Oxford Academic Google Scholar Zsolt Radi, Zsolt Radi TESCAN Brno s.r.o, Brno, Jihomoravsky kraj, Czech Republic Search for other works by this author on: Oxford Academic Google Scholar Jaroslav Jiruše, Jaroslav Jiruše TESCAN Brno s.r.o, Brno, Jihomoravsky kraj, Czech Republic Search for other works by this author on: Oxford Academic Google Scholar Lukáš Hladík, Lukáš Hladík TESCAN ORSAY HOLDING, a.s., Brno, Jihomoravsky kraj, Czech Republic Search for other works by this author on: Oxford Academic Google Scholar Olivier Salord, Olivier Salord Orsay Physics, Fuveau, Provence-Alpes-Cote d'Azur, France Search for other works by this author on: Oxford Academic Google Scholar Anne Delobbe Anne Delobbe Orsay Physics, Fuveau, Provence-Alpes-Cote d'Azur, France Search for other works by this author on: Oxford Academic Google Scholar Microscopy and Microanalysis, Volume 26, Issue S2, 1 August 2020, Pages 412–413, https://doi.org/10.1017/S1431927620014580 Published: 01 August 2020

3D electron backscatter diffraction study of α lath morphology in additively manufactured Ti-6Al-4V

Titanium alloys exhibit complex, multi-phase microstructures which form during liquid-solid and solid-solid phase transformations. These phase transformations govern the microstructural evolution and are potentially more complex during additive manufacturing due to large thermal gradients and inhomogeneities. The prototypical fundamental unit of titanium microstructures are the α laths, and investigations into their three-dimensional morphology may provide new insights. A prior β-grain boundary, 3-variant clusters and interconnected laths were studied in 3D in electron-beam printed Ti-6Al-4V using a plasma FIB. These key features are of interest for studying variant selection in additive manufacturing.

Prognostic significance of preoperative plasma fibrinogen levels in primary gastrointestinal stromal tumours: a retrospective cohort study

Improved prediction of prognosis for gastrointestinal stromal tumours (GISTs) has become increasingly important since the introduction of targeted therapy. Here, we aimed to evaluate the prognostic significance of preoperative plasma fibrinogen (Fib) levels in patients with primary GISTs and to analyse their correlations with clinicopathological characteristics. A total of 201 previously untreated patients with primary GISTs who had undergone radical surgery at our institution between October 2004 and July 2018 were enrolled. The optimal cut-off value for Fib levels was calculated using time-dependent receiver-operating characteristic curve analysis. RFS, the primary endpoint, was calculated by the Kaplan-Meier method and compared by the log-rank test. Univariate and multivariate Cox regression models were calculated. High preoperative plasma Fib levels were detected as an independent adverse prognostic factor (p = 0.008, hazard ratio 3.136, 95% CI 1.356‒7.256). Furthermore, high preoperative plasma Fib levels also indicated a poor prognosis within the modified National Institutes of Health (mNIH) high-risk subgroup (p = 0.041). In addition, preoperative plasma Fib levels showed a positive correlation with several prognostic factors and even a linear relationship with tumour size (Spearman correlation coefficient [r] = 0.411, p < 0.001). Our results suggest that high preoperative plasma Fib levels may indicate a poor prognosis in patients with primary GISTs. As a cost-effective biomarker, preoperative assessment of plasma Fib levels may help to further risk stratify patients with mNIH high-risk GISTs and instruct the application of targeted therapy.

Coupled Broad Ion Beam–Scanning Electron Microscopy (BIB–SEM) for polishing and three dimensional (3D) serial section tomography (SST)

Here we describe the first automated fully integrated in-microscope broad ion beam (BIB) system. Ar+-BIB has several advantages over Ga+ focused ion beam (FIB) and Xe+ plasma-FIB (PFIB) methods inducing less beam damage, especially for ion beam sensitive materials. It can mill areas several orders of magnitude larger (up to millimetre scale), and is not confined to the edge of the sample with associated curtaining issues. BIB is shown to have sputter rates up to five times higher than comparable FIB techniques. This new coupled BIB–SEM system (commercial name ‘iPrep™II’) enables in-microscope surface polishing to remove contaminants or damage for two dimensional (2D) imaging, as well as automated serial section tomography (SST) by milling and imaging hundreds of slices, cost and time efficiently. The milled slice thickness can be controlled from a few nanometers up to a micrometre. A novel sample transfer, handling and interlock system allows automated and sequential BIB polishing, scanning electron microscopy (SEM) and analysis by secondary electron (SE) imaging, electron back scatter diffraction (EBSD) and energy dispersive spectroscopy (EDS) for 3D microstructure analysis. Furthermore, insulating surfaces can be sputter coated after milling each slice to reduce charging during SEM analysis. The performance of the instrument is demonstrated through a series of case studies across the materials, earth and life sciences exploiting the imaging, crystallographic and chemical mapping capabilities. These include the study of butterfly defects in bearing steels, meta-stable intermetallic phases in bronze bearings, shale gas rock, aluminium plasma electrolytic oxide (PEO) coatings as well as liver and mouse brain tissues.

Novel Methods for Recording Stress-Strain Curves in Proton Irradiated Material

Proton irradiation is often used as a proxy for neutron irradiation but the irradiated layer is typically <50 μm deep; this presents a problem when trying to obtain mechanical test data as a function of irradiation level. Two novel methodologies have been developed to record stress-strain curves for thin proton-irradiated surface layers of SA-508-4N ferritic steel. In the first case, in-situ loading experiments are carried out using a combination of X-ray diffraction and digital image correlation on the near surface region in order to measure stress and strain, thereby eliminating the influence of the non-irradiated volume. The second approach is to manufacture small-scale tensile specimens containing only the proton irradiated volume but approaching the smallest representative volume of the material. This is achieved by high-speed focused ion beam (FIB) milling though the application of a Xe+ Plasma-FIB (PFIB). It is demonstrated that both techniques are capable of recording the early stage of uniaxial flow behaviour of the irradiated material with sufficient accuracy providing a measure of irradiation-induced shift of yield strength, strain hardening and tensile strength.

Fibrinogen and Albumin Score Changes during Preoperative Treatment Can Predict Prognosis in Patients with Locally Advanced Rectal Cancer.

Background Fibrinogen (Fib) and albumin (Alb) levels are indicators of systemic inflammatory responses. Elevated Fib and decreased Alb levels are considered negative prognostic factors in different types of cancer. Here, we explored the prognostic value of changes in pre- and post- neoadjuvant chemoradiotherapy (NCRT) plasma fibrinogen and serum albumin (FA) scores in patients with locally advanced rectal cancer (LARC). Methods A total of 106 patients with LARC who underwent NCRT followed by surgical resection at Jinhua Municipal Central Hospital between 2011 and 2015 were analyzed. In addition, plasma Fib and serum Alb levels before and after NCRT were collected. FA scores were calculated based on the Fib and Alb levels dichotomized by clinical reference values. Patients were classified into two groups based on the changes in FA scores during NCRT: in group A, FA scores decreased or remained unchanged (n = 84), and in group B, FA scores increased (n = 22). Changes in FA scores were compared with patient outcomes. Results Increased FA scores were associated with worse disease-free survival (DFS) and overall survival (OS) in patients with LARC. The occurrence of systemic failure was higher in group B than in group A (40.9% vs. 19%, P = 0.032). In multivariate analysis, changes in FA scores, pretreatment carcinoembryonic antigen (CEA) levels, and pathologic differentiation were independent prognostic parameters for DFS and changes in FA scores and pretreatment CEA levels were independent prognostic parameters for OS. Conclusions Increased FA score after NCRT was an independent negative prognostic factor for DFS and OS in patients with NCRT-treated LARC.

Semi-Inverted Sample Preparation of Meteorites for High Resolution Analytical Electron Microscopy Using Correlative Raman Spectroscopy and Xe Plasma FIB

Semi-Inverted Sample Preparation of Meteorites for High Resolution Analytical Electron Microscopy Using Correlative Raman Spectroscopy and Xe Plasma FIB

Latest Developments in Multiple Ion Species Plasma FIB Technology

Journal Article Latest Developments in Multiple Ion Species Plasma FIB Technology Get access Brandon Van Leer, Brandon Van Leer Thermo Fisher Scientific, Materials & Structural Analysis, Eindhoven, the Netherlands Search for other works by this author on: Oxford Academic Google Scholar Mikhail Dutka Mikhail Dutka Thermo Fisher Scientific, Materials & Structural Analysis, Eindhoven, the NetherlandsThermo Fisher Scientific, Hillsboro, OR, USA Search for other works by this author on: Oxford Academic Google Scholar Microscopy and Microanalysis, Volume 25, Issue S2, 1 August 2019, Pages 570–571, https://doi.org/10.1017/S1431927619003581 Published: 01 August 2019

Xe Plasma vs. Gallium FIB Delayering

Abstract Liquid metal ion and plasma beam FIB systems are widely used in the semiconductor industry for TEM lamella preparation, circuit edit, and cross-sectional analysis. This article compares the deprocessing capability of a Ga FIB with that of a Xe plasma FIB. Both systems were used to delayer an Intel 14 nm processor from M8 down to the transistor contacts. As the images in the article show, a 100 × 100 µm window was opened by the Xe plasma FIB and a 20 × 20 µm window was opened with the Ga FIB. Related issues such as processing time, end point detection, and surface roughness are also discussed.

Using a Plasma FIB Equipped with Xe, N2, O2 and Ar for Atom Probe Sample Preparation – Ion Implantation and Success Rates

Using a Plasma FIB Equipped with Xe, N₂, O₂ and Ar for Atom Probe Sample Preparation – Ion Implantation and Success Rates

On the Application of Xe+ Plasma FIB for Micro-fabrication of Small-scale Tensile Specimens

In order to perform site-specific mechanical studies to examine the contribution or interaction of a material constituent, a reliable methodology for the production of small-scale samples is required. With the high milling rates achievable with the newly developed Xe+ plasma FIB (PFIB), it is now possible to manufacture specimens approaching the smallest representative volume (SRV). In this study, a methodology has been developed that allows for the manufacture of mesoscale specimens approaching SRV to be tested in tension. It is demonstrated that yield and tensile strength measured in specimens of this scale are representative of bulk behaviour, of the properties measured the strain hardening exponent was found to be dependent on scale.

Correlation between prognosis and laboratory parameters of complete deafness in patients with sudden deafness

Objective: To study the correlation between the prognosis of sudden deafness and laboratory indicators, and to provide a theoretical basis for clinical evaluation of prognosis and selection of appropriate interventions.Method: A retrospective analysis of 123 cases of total deafness was conducted(all frequencies decreased with 250-8 000 Hz average hearing threshold ≥ 81 dB HL). All patients admitted to the hospital received laboratory test within 24 hours and underwent a unified treatment: alprostadil + mecobalamin + citicoline sodium phosphate + Ginkgo biloba extract + batroxobin + methylprednisolone (patients with hypertension or diabetes were given retro-auricular injection). After 2 weeks of comprehensive treatment, the pure tone audiometry was reviewed and the clinical efficacy was evaluated. According to the prognosis, the patients were divided into the healing group, the marked effective group, the effective group and the ineffective group. The laboratory indicators included: white blood cell count, neutrophil percentage, neutrophil lymphocyte ratio(NHR), erythrocyte sedimentation rate, blood lipid, red blood cell count, hemoglobin(Hb), plasma fibrinogen content(FIB). Result: There were no significant differences in white blood cell count, neutrophil percentage, NHR, erythrocyte sedimentation rate, blood lipid index and red blood cell count between different prognosis groups(all P>0.05). The differences of FIB and Hb were statistically significant(P<0.05). The overall prognosis was negatively correlated with FIB and positively correlated with Hb. Patients with vertigo had a worse prognosis and a higher plasma FIB level than those without vertigo(P<0.05), but there was no significant difference of Hb between patients with and without vertigo(P>0.05). Conclusion: FIB and Hb can be used as correlative indexes to evaluate the prognosis of patients with sudden deafness, and the effects of vertigo and other associated symptoms on the prognosis should be comprehensively analyzed. .

Application of Plasma FIB to Analyze a Single Oxide Inclusion in Steel

We demonstrate that Plasma Dual Beam focused ion beam (PFIB) milling can be used for high-resolution three-dimensional chemical study of a single non-metallic inclusion in steel. A CaO-Al2O3-MgO inclusion (~ 10 μm) on a polished cross-section of steel sample was located and milled using a Xe+ ion beam. A secondary electron image and EDS map of every section were recorded and subsequently processed to show the 3D chemistry and morphology of the inclusion.

MultiScale and MultiTime Image-Based Control and Characterization of Lithium-Ion Batteries and Materials

Lithium Ion batteries are the main energy storage devices today, from portable devices to electric vehicles. From improving the understanding of their properties, their ageing, or their modes of failures, to investigating new materials and designs, image-based analyses and measurements can play a key role to support the industry and research in this sector. From X-ray Computed Tomography (CT) to FIB-SEM (Focused-Ion Beam – Scanning Electron Microscopy), including recent Plasma FIB, images can be acquired to display the whole assembly, down to the microstructure of the materials involved. Thermo Scientific™ Avizo™ Software (Thermo Fisher Scientific, Waltham, MA, US) allows for visualizing, processing, and quantifying such data in a controlled, robust and reproducible manner, and can therefore help at all stages. In this paper, we present images and analyses results from different experiments, at the micro- and nano-metric scales, covering problematics of battery ageing, defect identification and detailed analysis using correlative microscopy from microCT to FIB-SEM.

(Invited) 3D Imaging Options of Battery Electrodes

There are different ways to create a 3D image of the battery electrodes. MicroCT uses the absorption of X-rays to create a 3D reconstruction. The Field of View is large enough to be representative with regard to the grain sizes. However, the submicron porosity in the electrodes is typically not well captured by microCT because of its limited resolution. The FIBSEM technique which uses a Galium ion beam for sectioning and an electron beam for imaging has high enough resolution to resolve all porosity. However, the Field of View is typically of the order of 10 micrometer; which is not always big enough to create a representative model of the pore space. PlasmaFIB can fill the gap between the Gallium FIB and the microCT on most liquid electrolyte lithium ion cells. However, for some solid state batteries, an even bigger volume is needed. This is where slicing with a laser can be used. In this presentation examples are covered of 3D imaging with microCT, laser sectioning and both Gallium and Plasma FIB.