Search

PURPOSE: Older adults have unique risk factors for poor outcomes after hematopoietic stem-cell transplant (HSCT). We sought to determine the impact of our multidisciplinary supportive care program, Enhanced Recovery after stem-cell transplant (ER-SCT), on survival outcomes in patients age 65 years and older who underwent HSCT. PATIENTS AND METHODS: In this retrospective study, clinicodemographic data, nonrelapse mortality (NRM), overall survival (OS), and relapse were compared between 64 patients age 65 years and older who underwent allogeneic stem-cell transplant during ER-SCT program's first year, October 2017 through September 2018, and 140 historical controls age 65 years and older who underwent allogeneic HSCT, January 2015 through September 2017. RESULTS: In the ER-SCT cohort, 41% (26 of 64) of patients were women, and the median (range) age was 68 (65-74) years; in the control cohort, 38% (53 of 140) of patients were women, and the median (range) age was 67 (65-79) years. Hematopoietic cell transplant comorbidity index and donor type/cell source were similar between cohorts. The ER-SCT cohort had a lower 1-year NRM rate (13% v 26%, P = .03) and higher 1-year OS rate (74% v 53%, P = .007). Relapse rate did not differ significantly between cohorts. In multivariate analyses, ER-SCT was associated with improved 1-year NRM (hazard ratio, 0.4; 95% CI, 0.2 to 0.9; P = .02) and improved 1-year OS (hazard ratio, 0.5; 95% CI, 0.3 to 0.9; P = .03). CONCLUSION: A multidisciplinary supportive care program may improve NRM and OS in older patients undergoing allogeneic HSCT. Randomized studies are warranted to confirm this benefit and explore which program components most contribute to the improved outcomes.

Much of UK upland peat is in a drained and/or degraded state, meaning it is a net source of CO2 emissions to the atmosphere. Typical restoration methods, such as rewetting, can improve this, however most restoration projects only achieve a lowering or cessation of emissions with few achieving a net-negative carbon balance. In this new demonstrator project, Greenhouse Gas Reduction – Peat, we are trialling methods of supressing methane emissions as well increasing carbon sequestration so that carbon negative restoration projects can be achieved.The projects aims to accelerate the transition from degraded, burn-managed heather (Calluna vulgaris) bog to actively peat-forming bog, while minimising wildfire risk and CH4 emissions. We will present preliminary results and further plans for three techniques, trialled alongside typical gully blocking:1) Sphagnum planting: This ‘nature-based’ intervention will involve Sphagnum (a peat forming moss species) establishment using micropropagated assemblages of hummock-forming species which show the highest rates of C accumulation. During the first years of Sphagnum growth, CO2 sequestration may be in excess of long-term peat accumulation rates as a functional upper ‘acrotelm’ layer re-establishes. Sphagnum can also act as a CH4 biofilter, improving the net greenhouse gas balance.2) Heather mowing and biochar production: As an alternative to managed burning, we will harvest old heather biomass using low-ground pressure vehicles, followed by biochar production and re-application. Biomass removal will reduce wildfire risk, while controlled pyrolysis will avoid damage to Sphagnum/peat from burning, and enhance biomass conversion to biochar above that achieved in uncontrolled burns.3) Suppression of methane production: CaSO4 can supress methane formation by offering a more energetically favourable metabolic pathway to microbes, meaning sulphate reducing bacteria are more active than methanogenic bacteria. This essentially ‘nudges’ the bacterial population in a direction more favourable for greenhouse gas balances.

Blanket bogs are a globally rare type of ombrotrophic peatland internationally recognized for long‐term terrestrial carbon storage, the potential to serve as carbon sinks, habitat provision and for their palaeoenvironmental archive. This habitat is protected in the European Union under the Habitats Directive (92/43/EEC), but a number of blanket bogs located in the Cantabrian Mountains (northern Spain), representing the southernmost known edge‐of‐range for this habitat in Europe, are currently not recognized and are at increased threat of loss.\ud \ud Using climatic data, topography, aerial photography and peat depth surveys, this study has identified 10 new areas of blanket bog located between the administrative regions of Cantabria and Castilla y León. Peat depth data and topography were used to provide a detailed geomorphological description and hydromorphological classification (mesotope units) of these currently unrecognized areas of blanket bog.\ud \ud Maximum peat depth measured across the 10 sites ranged from 1.61 to 3.78 m, covering a total area of 18.6 ha of blanket bog (>40 cm peat depth). The volume of peat accumulated across the sites was determined to be more than 216 000 m3 and is estimated to hold 19.89 ± 3.51 kt C. Twenty‐four individual hydrological mesotope units were described, indicating a diverse assemblage of blanket bogs in this region.\ud \ud The peatlands identified in this research extend the known limit of blanket bogs in Europe farther south than previously recorded and – combined with four other unprotected blanket bogs recently identified in the Cantabrian Mountains – these peatlands represent 10.5% of blanket bog currently recognized and protected in Spain. The range of anthropogenic pressures currently acting on peatlands in the Cantabrian Mountains indicates that without protection these important landforms and stored carbon may be lost. An urgent update of European peatland inventories is thus required to preserve these valuable carbon stores and potential carbon sinks.

Temporary permissions are often granted for track use on peatlands. However, even when peatland track designs attempt to minimise environmental impacts via use of mesh systems, such linear disturbances may have persistent impacts. We evaluated the surface peatland structure of five abandoned tracks (four with a mesh surface, one unsurfaced) with varying past usage frequencies, at an upland site in northern England. Simplification of the surface nanotopography was found on all tracks compared to surrounding control areas, with increased micro-erosion patterns in rutted areas, and invasive species on some treatments. The frequency of previous usage was not found to be a significant factor controlling nano-topographic loss. Edge effects and hillslope position were influential in places, but these effects were not consistent across treatments. Nano-topographic recovery was found to be inhibited when track usage commenced within a short time frame after track construction. Mesh tracks appear to create a spatial constraint leading to poor development of plants and a reduced ability to form characteristic structures which are integral to mire function.

Increasingly, patients age ≥65 years are undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT). Although age alone is a well-documented predictor of overall survival (OS) and nonrelapse mortality (NRM), growing evidence suggests that poor functional status and frailty associated with aging may have roles as well. Our goal in the present study was to identify and improve these and other aging-related maladies by developing a multimodal supportive care program for older allo-SCT recipients. We designed and implemented a multimodal supportive care program, Enhanced Recovery in Stem Cell Transplant (ER-SCT), for patients age ≥65 years undergoing allo-SCT. The ER-SCT program consists of evaluation and critical interventions by key health care providers from multiple disciplines starting before hospital admission for transplantation and extending through 100 days post-allo-SCT. We determined the feasibility of implementing this program in a large stem cell transplantation center. After 1 year of ongoing process improvements, multiple evaluations, and enrollment, we found that a dedicated weekly clinic was necessary to coordinate care and evaluate patients early. We successfully enrolled 57 of 64 eligible patients (89%) in the first year. Our data show that a multimodal supportive care program to enhance recovery for older patients undergoing allo-SCT is feasible. © 2021 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Extensive green roofs (EGRs) have been promoted as a multifunctional urban green infrastructure (UGI) solution that can ameliorate some of the negative environmental effects associated with urbanisation and provide habitat for wildlife. To date ecological EGR research remains limited, yet studying and understanding the ecology and ecological processes of these novel urban ecosystems could maximise their potential to conserve biodiversity and deliver multiple ecosystem services to urban areas. Here we present an overview of how a novel ‘ecomimicry’ approach can be used to ensure that locally important habitats are created and restored as part of urban green infrastructure strategies, and that biodiversity is embedded at the heart of EGR design. This can help urban developments meet sustainability targets and contribute to the goal of no-net-loss of biodiversity. Conserving urban biodiversity through ecomimicry will increase opportunities for urban communities to reconnect with nature and improve the quality of life for people in cities.

BACKGROUND: Optimal conditioning regimen for older patients with myelofibrosis undergoing allogeneic hematopoietic cell transplantation (HCT) is not known. Likewise, role of dose intensity is not clear. METHODS: We conducted a non-randomized prospective phase II trial using low-dose, later escalated to high-dose (MAC) busulfan with fludarabine (Bu-Flu) in myelofibrosis patients up to 74 years. First 15 patients received intravenous busulfan 130 mg/m(2)/day on days −3 and −2 (“low dose”); 31 received high dose – either 100 mg/m(2)/day (days −5 to −2; n=4) or pharmacokinetic-guided area under the curve of 4,000 μmol.min (days −5 to −2; n=27). Primary endpoint was day 100 non-relapse mortality (NRM). FINDINGS: Median age was 58 years (interquartile range (IQR) 53–63). Dynamic international prognostic scoring system (DIPSS)-plus was intermediate (n=28) or high (n=18). Donors were related (n=19) or unrelated (n=27). Cumulative incidence of NRM was 9.7% (95% confidence interval (CI) 0-20.3) at day 100 and at 3 years in the high dose, while it was 0% in the low dose group at day 100, and increased to 20% (95% CI 0-41.9) at 3 years. With a median follow up of 5.1 years (IQR 3.8–6), 3-year relapse was 32.3% (95% CI 15.4-49.1) in high dose versus 53.3% (95% CI 26.6-80.1) in low dose; event-free survival was 58% (95% CI 43-78%) versus 27% (95% CI 12-62%), and overall survival was 74% (95% CI 60-91%) versus 60% (95% CI 40-91%) respectively. In multivariate analysis, high dose busulfan had a trend towards lower relapse (Hazard ratio (HR) 0.44, 95% CI, 0.18-1.07, p=0.07), with no impact on NRM. INTERPRETATION: Intensifying Bu-Flu regimen using pharmacokinetic-monitoring appears promising in reducing relapse without increasing non-relapse mortality. FUNDING: The study was supported partly by Otsuka pharmaceutical and partly by the Cancer Center Support Grant (NCI Grant P30 CA016672). TRIAL REGISTRATION: ClinicalTrials NCT00475020

Background Older patients undergoing allogeneic stem cell transplant (SCT) have inferior outcomes. They have limited physiological reserves, which makes them more susceptible to toxic effects of conditioning regimens. Supportive care directed at maintaining and augmenting their limited functional reserve may reduce non-relapse mortality (NRM). We studied impact of a multidisciplinary supportive care and prehabilitation program (ER-SCT) and compared one-year NRM with a historical control group. Methods Between 1/1/15 and 9/30/18, 204 patients ≥ 65 years old underwent allogeneic SCT at our institution. ER-SCT program started on 10/1/17 and 57 of 64(89%) eligible patients participated during the first year. All 64 patients were included in the ER-SCT cohort, while patients treated between 1/1/15-9/30/17 were in the control group. ER-SCT program consisted of a prehabilitation phase prior to admission. Patients were evaluated by a multidisciplinary team consisting of a geriatrician, physical medicine and rehabilitation physician, physical therapist, occupation therapist, dietician, nurse, and a pharmacist specializing in SCT. Preexisting chronic conditions were optimized and recommendations were made for nutrition, exercise, and coping strategies. During hospitalization, fluid usage and medication choice / doses were optimized for older patients to prevent side effects such as fluid overload and delirium. Physical therapy, occupational therapy and nutrition counselling was continued. The team continued to follow and intervene as needed after discharge from the hospital. Results Median age was 68 (65-79) with 36 (18%) patients >than 70 years. Diagnoses included AML 96 (47%), MDS 57(28%), MPD 26 (13%), ALL 8(4%), and other 17 (8%). 103 (51%) had high or very high disease risk index (DRI). HCT-CI score was >3 in 80 (39%). Donor types included 127 (62%) matched unrelated, 57(28%) matched related and 20(10%) haploidentical. The NRM at 1 year was 13% in ER-SCT cohort vs 26% (p=0.03) in the control cohort. Multivariate analysis adjusting for GVHD prophylaxis and conditioning regimen, age, DRI, HCT-CI, donor type and graft source showed that ER-SCT HR=0.4 (0.2-0.9, P=0.02), comorbidity score Conclusion Although the data from this retrospective sequential cohort analysis cannot be conclusive, they do suggest that a multidisciplinary supportive care program (ER-SCT) may reduce NRM in older patients undergoing allogeneic SCT.

The Ecosystem Approach introduced in 1994 through the Convention on Biological Diversity, together with related Ecosystem-based Management and Landscape Approaches, are frequently called upon to improve ecological impact assessment. Current practice typically does not have such a systems focus and we explore the potential for explicitly adopting an Ecosystem Approach in the Environmental Impact Assessment process using wind energy development on peatland, in Scotland, as a case study. Based on a review of 21 windfarm projects (>50 MW) approved by the Scottish Government we provide an overview of current practice and identify and discuss how the 12 principles of the Ecosystem Approach can help identify options for more appropriate impact assessment. These include defining functional units of analysis that reflect the spatial and temporal linkages of peatland elements through hydrological connections, rather than a focus on individual vegetation types and simple distance buffers. Our conclusions are not limited to peatland and are relevant wherever meaningful functional management units can be defined, including in marine environments. Our results also show that environmental statements for wind energy development in Scotland largely ignore ecosystem services and the people that benefit from them. As for threatened species and other biodiversity features, an Ecosystem Approach is a prerequisite to the meaningful inclusion of ecosystem services in impact assessment.

The chapter argues that the challenges of globalization to contract law are best met through parties' approaching contracting in a relational manner and through bottom-up harmonization of terms, not through harmonization of contract law systems.

A combination of landform and climate suitable for both blanket mire formation and windfarm construction means that many windfarms have been, and continue to be, constructed on peat soils. Renewable energy sources are increasingly being adopted in order to reduce carbon emissions. Meanwhile peatlands are becoming increasingly recognised globally as some of the most carbon-rich of all terrestrial habitats. When a windfarm is constructed on peat it is inevitable that some of the carbon stored in the peat will be lost through oxidation of the peat. The main source of such disturbance is the network of access roads built for construction and maintenance. The most recent research suggests that potential carbon losses resulting from windfarm construction within a natural peat bog mean that there may be no net carbon benefit from the windfarm.

Mires, or peat-forming systems, have traditionally been recognised as falling into two broad peat-forming types – minerotrophic fens fed by groundwater or collected surface water, and ombrotrophic bogs fed exclusively by direct precipitation. Different types of fen can then be distinguished based on sources of water and rates of water supply. In contrast, ombrotrophic bogs can be classified according to their morphology, position within the landscape and consequent developmental history. A few ‘mixed’ or ‘intermediate’ mire types can also be identified.

Introduction The aim of this study is to determine if right arm peripherally inserted central catheters (PICCs) experienced fewer complications while controlling for gender, hand dominance, history of malignancy, dwell time and catheter size. Methods This was an intention-to-treat randomized controlled trial conducted in an academic medical center on two different sites between September 2012 and September 2015. All patients older than 18 years or age without known history of previous central line, contraindication to the use of a specific arm or hospitalized in the intensive care unit regardless of coagulation status, were considered for the study. Participants were randomized to the left or right arm group and were followed until catheter removal. Data collected included: PICC characteristics, insertion details, gender, arm dominance, history of malignancy, reason for insertion/removal, incidence of a complication and total dwell time. One-tailed hypothesis testing using a univariate logistic regression with odds ratio (OR) calculation was used to analyze the results. There were 202 patients randomly assigned, totaling 7657 catheter-days; 103 patients to the right-side group and 99 patients to the left-side group. Results Participants in both groups were statistically equivalent for right handedness, gender, oncologic status, average dwell time and total catheter days. The overall incidence of complications on the right side was 23% versus 34% on the left side, confirming the hypothesis that right-sided insertions led to fewer complications (p = 0.046). The risk of a complication was reduced by 40% with right-sided insertion (OR 0.58 (CI: 0.31-1.09). Conclusions This study indicated fewer complications with right-sided insertion irrespective of hand dominance.

Posterior spinal stabilization is a technically demanding procedure which is increasing in popularity. Since this increase in popularity, complications, including screws misplacement, are being highlighted. Accuracy rates are higher when imaging modalities are used intraoperatively. Vascular injuries following posterior spinal stabilization are rare and are usually discovered late on subsequent imaging. Immediate perioperative compromise is rare, but nonetheless, resultant vascular injuries can be life threatening. A 72-year-old woman had a posterior spinal stabilization for severe pain caused by discitis. Routine computed tomography scan, 2 weeks postoperatively, detected an incidental thoracic aortic injury due to a misplaced pedicle screw. Given the rarity of this complication, there is no guideline for the management of resultant aortic injuries. Options described in the literature include thoracotomy with open vascular repair and newer endovascular techniques. We describe a novel method of simultaneous endovascular repair of a thoracic aortic injury during posterior pedicle screw removal with the patient in the right decubitus position. Surgeons operating near high-risk vascular structures should use intraoperative imaging modalities to guide screw placement and reduce subsequent complication rates. During endovascular repair of resultant aortic injuries, several factors must be considered. In particular, the challenge of turning a patient with open groin access and an endovascular stent in place. This must be carried out with extreme care to avoid the following risks: loss of access, damage to the access vessels and bleeding, displacement of the stent or deployment wires, and loss of the sterile field.

Aim PACS and teleradiology systems have led to marked changes in the traditional relationship between referring clinicians and hospital radiology departments. The aim of this study was to assess which factors influence clinicians’ satisfaction with modern radiology services. Method An Internet-based survey questionnaire was sent to all referring clinicians within a large hospital network. Results Fifty-eight percent of 316 clinicians responded to the survey. Seventy percent felt PACS installation had improved reporting time, and 56% felt it had improved working patterns for medical staff. Approachability of radiologists was the only factor significantly associated with increased satisfaction (p = 8 × 10–8). A number of factors were found to be significantly associated with the perceived value of radiology reports, and these are discussed. An increase in clinicians’ confidence in their own radiological skills was not associated with a decrease in the value they placed on radiology reports. Conclusion The only factor significantly associated with improved clinician satisfaction was the availability of an approachable radiology service. Availability of PACS did not appear to undermine the value placed on radiology reports.

“Lovecraft” is a prominent adult sex shop in Toronto, Ontario. 1 One can find a wide variety of toys, videos, and libido-enhancing thrills at this Toronto hot-spot. 2 Surprisingly, however, nearly ...

This thesis devises and tests an approach to understanding archaeological sites of convict labour in an Australian context. It is centred upon a seemingly simple question: was convict labour motivated more by punishment or profit? Focussing on those places where the government retained direct control of convict labour, this thesis proposes an analytical framework that can form the foundation of discussions into the role and residues of convict labour in Australia. Such a framework is required, with research into the convict past marked by a growing disconnect between the archaeological and historical disciplines. The model presented for discussion posits that there are two main analytical elements that should be discussed when engaging with landscapes of convict labour: the setting and process. The latter, in particular, presents a multi-faceted way of examining these landscapes, encouraging their analysis through a tripartite filter: organisation (how the convict labour was managed and deployed), supervision (how the labour was directed and controlled) and production (the economic basis of the convict labour). This thesis tests the model by applying it to five case study sites. These were established by the government to exploit Van Diemen's Land's (Tasmania) coal resource through the deployment of convict labour between ca.1822 and 1848. By drawing upon the archaeological and historical record, this research analytically deconstructs these places using the devised model. Focus is placed upon the role of penological aims in their formation and development, in particular the tension engendered between the motives of punishment and profit. It finds that these places were formed and developed in response to complex multi-scalar influences and the transformative effects of the power dynamics which were played out within them. Importantly, this thesis observes that these places of convict labour are marked by an ambiguity that resulted in a melded landscape where the formative motivators of punishment and profit co-existed, the disentanglement of which requires the application of archaeological and historical methodology.

Cities dominated by impervious artificial surfaces can experience a multitude of negative environmental impacts. Restoration of green infrastructure has been identified as a mechanism for increasing urban resilience, enabling cities to transition towards sustainable futures in the face of climate-driven change. Building rooftops represent a viable space for integrating new green infrastructure into high-density urban areas. Urban rooftops also provide prime locations for photovoltaic (PV) systems. There is an increasing recognition that these two technologies can be combined to deliver reciprocal benefits in terms of energy efficiency and biodiversity targets. Scarcity of scientific evaluation of the interaction between PVs and green roofs means that the potential benefits are currently poorly understood. This study documents evidence from a biodiversity monitoring study of a substantial biosolar roof installed in the Queen Elizabeth Olympic Park. Vegetation and invertebrate communities were sampled and habitat structure measured in relation to habitat niches on the roof, including PV panels. Ninety-two plant species were recorded on the roof and variation in vegetation structure associated with proximity to PV panels was identified. Almost 50% of target invertebrate species collected were designated of conservation importance. Arthropod distribution varied in relation to habitat niches on the roof. The overall aim of the Main Press Centre building green roof design was to create a mosaic of habitats to enhance biodiversity, and the results of the study suggest that PV panels can contribute to niche diversity on a green roof. Further detailed study is required to fully characterise the effects of PV panel density on biodiversity.

Material issues that impact the applicability of Ni based silicides to CMOS flows were studied, including the excessive silicidation of narrow features, the growth kinetics of Ni 2 Si and NiSi on single-crystalline and poly-crystalline silicon and the thermal degradation mechanisms. Ni 2 Si was found to grow by diffusion controlled kinetics with an activation energy of about 1.55 eV on single-crystalline Si. As a result, the excessive silicidation in small features can be reduced in a 2-step Ni-silicide process by reducing the thermal budget of the first RTP step. The mechanisms of thermal degradation of NiSi were studied. Thin NiSi films were found to degrade morphologically while still in the monosilicide phase. Thick NiSi films degrade morphologically at low temperatures and by transformation to NiSi 2 at high temperatures. The reaction of Ni with SiGe substrates and the effect of Ge on the thermal degradation of the Ni-germanosilicide were investigated. Activation energies for the thermal degradation of Ni(SiGe) on SiGe were found to be significantly smaller than the values found for the thermal degradation of NiSi on pure Si. The effect of alloying Ni with Pt or Ta was studied. NiSi films alloyed with Pt or Ta are found to be thermally more stable compared to pure NiSi. Alloying with Pt was found to improve the thermal stability of NiSi on narrow poly-Si gates. The kinetics of Ni 2 Si and NiSi formation on poly silicon were determined as well as their dependence on dopants. The presence of B in high doses was found to slow down the silicide formation significantly. Dopant segregation to the NiSi/oxide interface was observed, which is believed to be responsible for the observed shifts in work function. The sheet resistance of fully Ni-silicided 100 nm poly Si/oxide stacks is found to be stable up to 800 °C.

The reaction of Ni films with a Si"0"."8Ge"0"."2 alloy is studied in the temperature range of 200-750 ^oC from the point of view of process window, morphology of the resulting silicide, and mechanisms of degradation at high temperatures. The effect on the reaction of substrate crystallinity (single crystal and polycrystalline Si"0"."8Ge"0"."2), dopants (arsenic and boron) and process parameters is investigated. Sheet resistance measurements, X-ray diffraction and scanning electron microscopy were used for film characterization. Ni-rich germanosilicide is formed at low (

Excessive Ni-silicide formation is observed at the edges of poly gates and source/drain lines. The excessive silicidation results in locally completely silicided poly gates and in very high junction leakage in small source/drain islands. It was studied whether the excessive Ni-silicide formation in narrow features can be reduced in a two-step Ni-silicide process in which the thermal budget of the first RTP step is just enough to fully react the Ni. It was found that the excessive silicidation can be avoided either by reducing the anneal temperature or by reducing the anneal time. Reducing the thermal budget of the first RTP step was found to significantly improve the junction leakage in small source/drain islands for As junctions. No improvement was observed for B junctions. The latter is thought to be related to the presence of NiSi"2 pyramids.

Current techniques for definition of the junction recess suffer from degradation of the Si crystal quality. We demonstrate the suitability of in situ chemical vapour etching (CVE) by HCl as an alternative Si etch back technique. The process has been developed in a standard epitaxial growth system and allows Si thinning without defect creation and without contamination of the remaining Si surface. In situ combination of Si etch back with facet free selective epitaxial in situ doped SiGe re-growth, makes the technique very attractive. It is a suitable technology for the fabrication of ultra-shallow source/drain junctions. The replacement of Si by SiGe might be a possible route to reduce source/drain contact resistance.

The scaling behavior of Co, Co-Ni and Ni silicides to sub-40 nm gate length CMOS technologies with sub-100 nm junction depths was evaluated. Limitations were found for Co and Co-Ni alloy silicides, which exhibited an increase in sheet resistance at gate lengths below 40 nm and required high processing temperatures to achieve low junction leakage. Ni silicide was shown, in contrast, to have good scaling behavior, with a decrease in sheet resistance for decreasing gate lengths down to 30 nm, lower diode leakage (at similar sheet resistance) and lower silicide to p+ Si contact resistance than Co silicide. Key material issues impacting the applicability of NiSi to CMOS technologies were investigated. Studies of the kinetics of Ni2Si growth were used to design a process that avoids excessive silicidation of small features. The thermal degradation mechanisms of NiSi films were also studied. Thin films degraded morphologically with activation energies of ∼ 2.4 eV. Thick films degraded morphologically at low temperatures and by transformation to NiSi2 at high temperatures, suggesting a higher activation energy for the latter mechanism. Pt alloying was shown to help stabilize NiSi films against morphological degradation.

To get an insight in the diffusion behavior of boron after annealing and in particular its segregation characteristics towards the interface in oxide structures on silicon, it is necessary to probe the boron profile with very high accuracy and depth resolution. Sputter depth profiling as employed in secondary ion mass spectrometry (SIMS) is frequently used as the most suited tool for dopant profiling in view of its sensitivity and depth resolution. However, in order to determine the segregated boron peak, sub-nm depth resolution is required and artifacts such as beam induced broadening effects, potential ionization yield changes at interfaces, transient sputter yields need to be considered in detail. When reducing the primary beam energy the depth resolution can be improved and sub-nm depth sensitivity can be demonstrated. However, comparisons with high-resolution elastic recoil detection analysis demonstrate that even under those conditions no reliable depth profile can be obtained in the first nm near the surface nor even in the oxide part of the profile, where no ionization nor sputter yield transients are expected. Enhanced beam induced migration of boron during the initial phase of the bombardment needs to be invoked to explain the results.

As scaling progresses, conventional Co/Ti silicidation is facing difficulties related to the nucleation of the low resistive Co-disilicide phase during the second RTP step of silicidation. When linewidths, junction depths and silicide thicknesses are being reduced, the RTP2 thermal process window narrows down rapidly. It is expected that the process window can be widened by alloying the Co film with Ni, because the presence of Ni lowers the nucleation barrier for the Co-disilicide phase. Replacing Co-disilicide by Ni-monosilicide is a promising alternative because the same silicide sheet resistance can be obtained with 35% less silicon consumption.

On annealing a boron implanted Si sample at similar to800 degreesC, boron in the tail of the implanted profile diffuses very fast, faster than the normal thermal diffusion by a factor 100 or more. ...

CoSi2 formed using a Ti cap has been shown to reduce any oxide or contaminants present during silicide growth to improve the uniformity of the silicide. However, as transistor dimensions shrink, a concern in using CoSi2 is the thermal process window for the second RTP step (RTP2). Thinner silicides agglomerate at lower temperatures but a minimum temperature is required for a uniform silicide with low junction leakage. This paper describes the results of a detailed investigation into the thermal processing of thin Ti-capped CoSi2 compatible with 0.13 μm CMOS technology. Ti-capped CoSi2 films of varying thickness on both poly and active regions were studied for three junction dopants, As, BF2, and B. The parameters investigated in the thermal processing were the temperature, time and ramp rates for RTP2. Sheet resistance, diode leakage, and interface roughness were measured as a function of the thermal processing. The results show that the optimal RTP2 thermal budget for thin Ti-cap CoSi2 on devices is 800°C for 120 s with high ramp rates giving possible leakage improvement.

In this work, the phase formation is compared for Ni- and Co-silicidation with and without Ti cap. In addition, the electrical performance of Ni-silicidation with and without Ti-cap is investigated and compared to the performance of a Co-silicidation process with a Ti cap that has the same Si consumption. The lateral confinement of the silicide in the active areas is also studied.