Defect structure of Czochralski silicon co-implanted with helium and hydrogen and treated at high temperature - pressure

Effect of stress created by Ar hydrostatic pressure (HP) up to 1.1 GPa during annealing at the high temperature (HT) 1070 K (HT-HP treatment) on microstructure of Czochralski grown silicon co-implanted with helium and hydrogen Si:(He,H) using the same doses of He+ and H₂+ (DH,He= 5·10¹⁶ cm⁻², at energy 50 and 150 keV, respectively) was investigated by means of X-ray (synchrotron) diffraction, transmission electron microscopy, and electrical measurements. The nanostructured sponge-like buried layers are formed in Si:(He,H) by annealing / high pressure treatment. Decreased interference, diffuse scattering and individual contrast are observed in the synchrotron topograms for HT-HP treated Si:(He,H). The treatment at 723 K and HP results in an additional donor formation as a sequence of the implantation-disturbed layer. The HP-mediated (retarded) out-diffusion of hydrogen and helium is in part responsible for the effects observed

Guidance on Noncorticosteroid Systemic Immunomodulatory Therapy in Noninfectious Uveitis: Fundamentals Of Care for UveitiS (FOCUS) Initiative

Topic: An international, expert-led consensus initiative to develop systematic, evidence-based recommendations for the treatment of noninfectious uveitis in the era of biologics. Clinical Relevance: The availability of biologic agents for the treatment of human eye disease has altered practice patterns for the management of noninfectious uveitis. Current guidelines are insufficient to assure optimal use of noncorticosteroid systemic immunomodulatory agents. Methods: An international expert steering committee comprising 9 uveitis specialists (including both ophthalmologists and rheumatologists) identified clinical questions and, together with 6 bibliographic fellows trained in uveitis, conducted a Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol systematic review of the literature (English language studies from January 1996 through June 2016; Medline [OVID], the Central Cochrane library, EMBASE, CINAHL, SCOPUS, BIOSIS, and Web of Science). Publications included randomized controlled trials, prospective and retrospective studies with sufficient follow-up, case series with 15 cases or more, peer-reviewed articles, and hand-searched conference abstracts from key conferences. The proposed statements were circulated among 130 international uveitis experts for review. A total of 44 globally representative group members met in late 2016 to refine these guidelines using a modified Delphi technique and assigned Oxford levels of evidence. Results: In total, 10 questions were addressed resulting in 21 evidence-based guidance statements covering the following topics: when to start noncorticosteroid immunomodulatory therapy, including both biologic and nonbiologic agents; what data to collect before treatment; when to modify or withdraw treatment; how to select agents based on individual efficacy and safety profiles; and evidence in specific uveitic conditions. Shared decision-making, communication among providers and safety monitoring also were addressed as part of the recommendations. Pharmacoeconomic considerations were not addressed. Conclusions: Consensus guidelines were developed based on published literature, expert opinion, and practical experience to bridge the gap between clinical needs and medical evidence to support the treatment of patients with noninfectious uveitis with noncorticosteroid immunomodulatory agents

МАТЕРІАЛИ, ЩО БАЗУЮТЬСЯ НА КРЕМНІЇ, ДЛЯ ЗАСТОСУВАННЯ У СПІНТРОНІЦІ

The effect of enhanced hydrostatic pressure (HP, up to 1.1 GPa) applied at up to 1270 K (HT) on Si:V, Si:Cr, Si:V,Cr and Si:Mn prepared by implantation of respective metallic ions (doses 1x1015 — 1x1016 cm-2, at energy 160 keV or 200 keV) into (001) oriented Czochralski grown Si, has been investigated by Secondary Ion Mass Spectrometry, magnetometry and X-Ray methods. Implantation produces amorphous silicon (a-Si) near the implanted ions range. Quasi — epitaxial re — growth of a-Si takes place at HT. The V, Cr and Mn concentration profiles do not depend markedly on HP if applied below 1000 K. Marked diffusion of implanted atoms toward the sample surface is observed in the case of processing at > 1000 K under 105 Pa, especially in the case of Si:Cr and Si:Mn. Under HP this diffusion is even more pronounced, re-crystallization of a-Si is retarded and the a-Si / Si interface becomes enriched with metallic atoms. Processing of Si:V, Si:Cr and Si:Mn at ≤ 723 K results in distinct ferromagnetic ordering, detectable also above 50 K. This means that the new Si-V, Si-Cr and Si-Mn materials belonging to the family of Diluted Magnetic Semiconductors may be produced.Методом масс-спектрометрии вторичного иона, магнитометрией и рентгеноскопическим методом было исследовано влияние повышенного гидростатического давления (ГД, до 1.1 ГПa) приложенного при температуре вплоть до 1270 K к Si:V, Si:Cr, Si:V,Cr и Si:Mn, изготовленных имплантацией соответствующих металлических ионов (дозы 1x1015 — 1x1016 см 2, с энергией 160 кэВ или 200 кэВ) в (001) ориентированный Si, выращенный методом Чохральского.Имплантация создает аморфный кремний (a-Sі) в области внедренного иона. Происходит квази-эпитаксиальный повторный рост a-Si при высокой температуре. Профили концентрации V, Cr и Мn не зависят заметно от ГД при температурах ниже 1000 K. Заметная диффузия внедренных атомов к поверхности образца наблюдается в случае обработки при температурах > 1000 K при 105 Па, особенно в случае Si:Cr и Si:Mn. При ГД эта диффузия даже более явно выражена, перекристаллизация a-Si замедляется и граница a-Si / Si становится обогащенной атомами металла. Обработка Si:V, Si:Cr и Si:Mn при температурах ≤ 723 K приводят к явному упорядочению ферромагнетика, наблюдаемому также при температурах выше 50 K. Это означает, что могут быть получены новые материалы Si-V, Si- Cr и Si-Мn, принадлежащие к классу разбавленных магнитных полупроводников.Методом мас-спектрометрії вторинного іона, магнітометрією і рентгеноскопічним методом було досліджено вплив підвищеного гідростатичного тиску (ГТ, до 1.1 ГПa) прикладеного до Si:V, Si:Cr, Si:V,Cr і Si:Mn при температурі аж до 1270 K, виготовлених імплантацією відповідних металевих іонів (дози 1x1015 — 1x1016 см2, з енергією 160 кеВ або 200 кеВ) у (001) орієнтований Si, який вирощено методом Чохральского. Імплантація створює аморфний кремній (a-Sі) в області включеного іона. Відбувається квазі-епітаксиальний повторний ріст a-Si при високій температурі. Профілі концентрації V, Cr і Мn не залежать помітно від ГТ при температурах нижчих 1000 K. Помітна дифузія включених атомів до поверхні зразка спостерігається у випадку обробки при температурах > 1000 K при 105 Па, особливо у випадку Si:Cr і Si:Mn. При ГТ ця дифузія навіть більш явно виражена, перекристалізація a-Si сповільнюється і границя a Si / Si стає збагаченою атомами металу. Обробка Si:V, Si:Cr і Si:Mn при температурах ≤ 723 K призводить до помітного упорядкування ферромагнетика, що спостерігається також при температурах вищих 50 K. Це означає, що можуть бути отримані нові матеріали Si-V, Si- Cr і Si-Мn, які належать до класу розведених магнітних напівпровідників

Defect structure of Czochralski silicon co-implanted with helium and hydrogen and treated at high temperature - pressure

Effect of stress created by Ar hydrostatic pressure (HP) up to 1.1 GPa during annealing at the high temperature (HT) 1070 K (HT-HP treatment) on microstructure of Czochralski grown silicon co-implanted with helium and hydrogen Si:(He,H) using the same doses of He+ and H₂+ (DH,He= 5·10¹⁶ cm⁻², at energy 50 and 150 keV, respectively) was investigated by means of X-ray (synchrotron) diffraction, transmission electron microscopy, and electrical measurements. The nanostructured sponge-like buried layers are formed in Si:(He,H) by annealing / high pressure treatment. Decreased interference, diffuse scattering and individual contrast are observed in the synchrotron topograms for HT-HP treated Si:(He,H). The treatment at 723 K and HP results in an additional donor formation as a sequence of the implantation-disturbed layer. The HP-mediated (retarded) out-diffusion of hydrogen and helium is in part responsible for the effects observed