scholarly journals Methods of trichlorosilane synthesis for polycrystalline silicon production. Part 2: Hydrochlorination and redistribution

2021 ◽  
Vol 7 (2) ◽  
pp. 33-43
Author(s):  
Vladimir N. Jarkin ◽  
Oleg A. Kisarin ◽  
Tatyana V. Kritskaya

Novel technical solutions and ideas for increasing the yield of solar and semiconductor grade polycrystalline silicon processes have been analyzed. The predominant polycrystalline silicon technology is currently still the Siemens process including the conversion of technical grade silicon (synthesized by carbon-thermal reduction of quartzites) to trichlorosilane followed by rectification and hydrogen reduction. The cost of product silicon can be cut down by reducing the trichlorosilane synthesis costs through process and equipment improvement. Advantages, drawbacks and production cost reduction methods have been considered with respect to four common trichlorosilane synthesis processes: hydrogen chloride exposure of technical grade silicon (direct chlorination, DC), homogeneous hydration of tetrachlorosilane (conversion), tetrachlorosilane and hydrogen exposure of silicon (hydro chlorination silicon, HC), and catalyzed tetrachlorosilane and dichlorosilane reaction (redistribution of anti-disproportioning reaction). These processes remain in use and are permanently improved. Catalytic processes play an important role on silicon surface, and understanding their mechanisms can help find novel applications and obtain new results. It has been noted that indispensable components of various equipment and process designs are recycling steps and combined processes including active distillation. They provide for the most complete utilization of raw trichlorosilane, increase the process yield and cut down silicon cost.

Author(s):  
V. N. Jarkin ◽  
O. A. Kisarin ◽  
T. V. Kritskaya

Novel technical solutions and ideas for increasing the yield of solar and semiconductor grade polycrystalline silicon processes have been analyzed. The predominant polycrystalline silicon technology is currently still the Siemens process including the conversion of technical grade silicon (synthesized by carbon-thermal reduction of quartzites) to trichlorosilane followed by rectification and hydrogen reduction. The cost of product silicon can be cut down by reducing the trichlorosilane synthesis costs through process and equipment improvement. Advantages, drawbacks and production cost reduction methods have been considered with respect to four common trichlorosilane synthesis processes: hydrogen chloride exposure of technical grade silicon (direct chlorination, DC), homogeneous hydration of tetrachlorosilane (conversion), tetrachlorosilane and hydrogen exposure of silicon (hydro chlorination silicon, HC), and catalyzed tetrachlorosilane and dichlorosilane reaction (redistribution of anti-disproportioning reaction). These processes remain in use and are permanently improved. Catalytic processes play an important role on silicon surface, and understanding their mechanisms can help find novel applications and obtain new results. It has been noted that indispensable components of various equipment and process designs are recycling steps and combined processes including active distillation. They provide for the most complete utilization of raw trichlorosilane, increase the process yield and cut down silicon cost


2021 ◽  
Vol 7 (1) ◽  
pp. 1-10
Author(s):  
Vladimir N. Jarkin ◽  
Oleg A. Kisarin ◽  
Tatyana V. Kritskaya

Novel technical solutions and ideas for increasing the yield of solar and semiconductor grade polycrystalline silicon processes have been analyzed. The predominant polycrystalline silicon technology is currently still the Siemens process including the conversion of technical grade silicon (synthesized by carbon-thermal reduction of quartzites) to trichlorosilane followed by rectification and hydrogen reduction. The cost of product silicon can be cut down by reducing the trichlorosilane synthesis costs through process and equipment improvement. Advantages, drawbacks and production cost reduction methods have been considered with respect to four common trichlorosilane synthesis processes: hydrogen chloride exposure of technical grade silicon (direct chlorination, DC), homogeneous hydration of tetrachlorosilane (conversion), tetrachlorosilane and hydrogen exposure of silicon (hydro chlorination silicon, HC), and catalyzed tetrachlorosilane and dichlorosilane reaction (redistribution of anti-disproportioning reaction). These processes remain in use and are permanently improved. Catalytic processes play an important role on silicon surface, and understanding their mechanisms can help find novel applications and obtain new results. It has been noted that indispensable components of various equipment and process designs are recycling steps and combined processes including active distillation. They provide for the most complete utilization of raw trichlorosilane, increase the process yield and cut down silicon cost.


Author(s):  
Сергей Борисович Казаков ◽  
Дмитрий Михайлович Шишов ◽  
Антон Игоревич Ларин ◽  
Александр Петрович Николаев ◽  
Аза Валерьевна Писарева

В статье представлен обзор существующих технических решений в сфере мониторинга и предотвращения апноэ во сне. Произведён анализ существующих аппаратов для предотвращения апноэ, который показал, что на рынке присутствует большое количество импортных моделей, однако они имеют довольно высокую цену. Разработанный нами Российский аналог проектируемого аппарата, при схожих характеристиках, будет иметь более привлекательную цену, чем у импортных приборов. Интегрирование датчика влажности в персональную маску пациента даёт возможность отслеживать остановки дыхания пациента во время сна, и тем самым включать процесс принудительной подачи дыхательной смеси именно в тот момент, когда она необходима для устранения патологии. Целью научной работы является разработка конструкции прибора и создание алгоритма программы для управления аппарата искусственной вентиляции лёгких для предотвращения апноэ во сне. Показана разработка структуры устройства аппарата. Подобран компрессор и датчик влажности с обоснованными характеристиками для создания аппарата, а также основные элементы. Разработана конструкция корпуса аппарата и разработана компоновка. Выполнено технико-экономическое обоснование разработки аппаратно-программного комплекса для предотвращения апноэ во сне. Показано, что себестоимость готового изделия достаточно конкурентна The article presents an overview of existing technical solutions in the field of monitoring and prevention of sleep apnea. An analysis of existing devices for preventing apnea was made, which showed that there are a large number of imported models on the market, but they have a fairly high price. The Russian analog of the designed device developed by us, with similar characteristics, will have a more attractive price than that of imported devices. The integration of the humidity sensor into the patient's personal mask makes it possible to monitor the patient's breathing stops during sleep, and thus enable the process of forced delivery of the respiratory mixture at the exact moment when it is necessary to eliminate the pathology. The purpose of the research is to develop the device design and create a program algorithm for controlling the artificial lung ventilation device to prevent sleep apnea. The development of the device structure is shown. The compressor and humidity sensor with reasonable characteristics for creating the device, as well as the main elements are selected. The design of the device body and its layout were developed. A feasibility study for the development of a hardware and software system for preventing sleep apnea has been completed. It is shown that the cost of the finished product is quite competitive


2020 ◽  
Vol 67 (1) ◽  
pp. 28-34
Author(s):  
Aleksandr V. Vinogradov ◽  
Aleksey V. Bukreev

When repairing and replacing electrical wiring in enterprises, the main difficulty is the lack or poor quality of documentation, plans for conductors laying. Distinguishing wires (cables) and their cores by the color of the shells or using tags attached to the ends is difficult if the shells have the same color and there are no tags. Devices and technical solutions used to identify wires and cables do not allow recognizing conductors without breaking the electrical circuit, removing insulation, and de-energizing the network. Searching for the right conductor is a time-consuming operation. (Research purpose) The research purpose is developing a new microcontroller device for identifying wires using an acoustic signal. (Materials and methods) Literature sources has been searched for devices for conductors identifying. (Results and discussion) The article proposes a method that involves feeding an acoustic signal to a wire at one point and capturing it at another, in order to recognize the desired wire. The article presents results of comparison of the developed microcontroller device for identifying conductors using an acoustic signal with known devices and methods for conductors recognizing. (Conclusions) The article reveals the shortcomings of existing methods and means of identifying wires and cables. Authors performed a theoretical calculation of the sound pressure in the conductor at a given distance. The article presents the calculation of speed of acoustic waves in conductors with different types of insulation. Authors designed a microcontroller device for identifying conductors using an acoustic signal and tested it. It was determined that the device increases the safety of work, reduces the cost of operating internal wiring and identification time; eliminates the violation of wire insulation, the need to disable electrical receivers. The convergence of theoretical calculations and experimental data was shown.


2021 ◽  
Vol 1 ◽  
pp. 131-140
Author(s):  
Federica Cappelletti ◽  
Marta Rossi ◽  
Michele Germani ◽  
Mohammad Shadman Hanif

AbstractDe-manufacturing and re-manufacturing are fundamental technical solutions to efficiently recover value from post-use products. Disassembly in one of the most complex activities in de-manufacturing because i) the more manual it is the higher is its cost, ii) disassembly times are variable due to uncertainty of conditions of products reaching their EoL, and iii) because it is necessary to know which components to disassemble to balance the cost of disassembly. The paper proposes a methodology that finds ways of applications: it can be applied at the design stage to detect space for product design improvements, and it also represents a baseline from organizations approaching de-manufacturing for the first time. The methodology consists of four main steps, in which firstly targets components are identified, according to their environmental impact; secondly their disassembly sequence is qualitatively evaluated, and successively it is quantitatively determined via disassembly times, predicting also the status of the component at their End of Life. The aim of the methodology is reached at the fourth phase when alternative, eco-friendlier End of Life strategies are proposed, verified, and chosen.


2012 ◽  
Vol 195 ◽  
pp. 283-288 ◽  
Author(s):  
Juergen Schweckendiek ◽  
Ronald Hoyer ◽  
Sebastian Patzig-Klein ◽  
Franck Delahaye ◽  
Gerry Knoch ◽  
...  

The large scale of production of modern PV manufacturing as well as the cost pressure demand a different approach to cleaning processes in semiconductor and PV applications. The subject of this presentation is, to highlight aspects of similarities and differences. Total added cost/m2of Si are estimated for typical PV manufacturing conditions and compared to semiconductor applications. Typical technical solutions are reviewed. They are compared to the anticipated technical and cost requirements in the near future according to PV roadmaps and cell concepts which are evident today. Starting with typical cleaning processes during the wafering (sawing, cleaning, separation) up to cell processing (texturing, diffusion, coating and plating) the main cleaning processes are presented and their specifics are indicated. Finally recontamination and conditioning in production lines are reviewed.


2012 ◽  
Vol 557-559 ◽  
pp. 1539-1542
Author(s):  
Jian Fang Wang ◽  
Ya Nan Lv ◽  
Yin Long ◽  
Cheng An Tao ◽  
Hui Zhu

In this paper, the graphene oxide reducing by photochemical-thermal reduction and high-temperature thermal reduction was studied to get qualified graphene and avoid the re-aggregation. The results show that graphene obtained by both of the two reduction methods all maintained the original well-layered morphology of the graphene oxide. The graphene had smooth surface and high quality as completely reduced by high-temperature thermal method. However, the reduction the photochemical-thermal reaction was not sufficient and caused many vesicles on the graphene surface due to the low temperature and the lack of reaction time.


Author(s):  
I. V. Grigoryev ◽  
◽  
O. A. Kunitskaya ◽  
Yu. V. Lanskikh ◽  
S. Yu. Sandakov ◽  
...  

Technical solutions that can be implemented to increase mileage of tires up to 35%, eliminate the emergency of tires of forest and agricultural machines, reduce fuel consumption, increase cross-country ability and stability of machines, reduce damage of soil of cutting areas are discussed. These innovative methods for management of durability of tires are already widely used abroad, in leading transport companies in Russia, at large agricultural enterprises, but are still not known in the logging industry. The main competitive advantages of these technical solutions are simplicity of the construction, installation and operation, as well as low cost. As a result of the analysis of the existing tire pressure monitoring systems, the authors suggest the principle of improving the construction, which increases its reliability and reduces the cost.


Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 70
Author(s):  
Cheng Liu ◽  
Xueyin Liu ◽  
Zhaoping Hou ◽  
Quanli Jia ◽  
Benjun Cheng ◽  
...  

Submicron-sized (~200 nm) aluminium boron carbide (Al8B4C7) particles were synthesised from Al, B4C and carbon black raw materials in a molten NaCl-based salt at a relatively low temperature. The effects of the salt type/assembly and the firing temperature on the synthesis process were examined, and the relevant reaction mechanisms discussed. The molten salt played an important role in the Al8B4C7 formation process. By using a combined salt of 95%NaCl + 5%NaF, an effective liquid reaction medium was formed, greatly facilitating the Al8B4C7 formation. As a result, essentially phase-pure Al8B4C7 was obtained after 6 h of firing at 1250 °C. This temperature was 350–550 °C lower than that required by the conventional direct reaction and thermal reduction methods.


2013 ◽  
Vol 31 (31_suppl) ◽  
pp. 268-268
Author(s):  
Susan Schreiner ◽  
Theresa Franco

268 Background: Reducing costs in health care is critical due to declining reimbursement. Physicians are often unaware of how their practices affect the cost of patient care and may have difficulty in making changes. The leadership of the Cancer Service Line believed a more targeted approach in sharing data would improve physician understanding and engagement to assist in greater standardization and cost reduction. Methods: An education and communication strategy was developed that involves the leadership of each specialty section of oncology. A dashboard was created with metrics such as clinic visits, surgical volume, cost per case, average length of stay, and net income. The data is presented in monthly, quarterly and annual time frames with trends to highlight progress and identify areas for improvement. Monthly meetings are conducted with key stakeholders to obtain critical feedback. Results: Consistent data has increased physician understanding of clinical businesses the business is doing and has prompted them to optimize clinical schedules and improve operational efficiencies. Outpatient and inpatient data regarding cost per case, ancillary costs, pharmaceutical usage, blood product utilization, and drug exchanges has driven practice changes. The ALOS is at almost an entire day below benchmarks and direct cost per case is at budgeted target. Standardization has occurred in the use of blood products and there has been an intentional shift of some interventions to the outpatient arena. Conclusions: The implementation of a robust education and communication strategy have resulted in active engagement and participation of physicians, significant practice changes in cancer care and heightened understanding of the relationship of practice to cost. A dashboard that trends relevant metrics shared at regular intervals with key providers impact the cost of cancer services without affecting the quality.


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