ОПТИМИЗАЦИЯ ПАРАМЕТРОВ УЛЬТРАЗВУКОВОЙ СИСТЕМЫ ПОВЫШЕННОЙ ЧАСТОТЫ ДЛЯ МИКРОСВАРКИ ПРОВОЛОЧНЫХ ВЫВОДОВ

Mathematical equations for resonant frequency and impedance of ultrasonic transducer for wire bonding were proposed. Clamping optimization of bonding tool was determined due to modelling of resonant frequency and impedance for standard and high frequency ultrasonic vibrations in ultrasonic system. It was shown that proposed technique gives good fit to the experimental data.Предложены математические выражения для резонансной частоты и импеданса ультразвукового преобразователя для микросварки проволочных выводов. Моделированием резонансной частоты и импеданса ультразвуковых преобразователей стандартной и повышенной частоты колебаний установлены оптимальные условия закрепления инструмента в ультразвуковой системе. Разработанная методика экспериментально подтверждена с помощью лазерного измерителя амплитуды колебаний

Hole Formation in Semiconductor Materials by Laser Microprocessing

The process of laser formation of microholes in semiconductor substrates using an EM-4452-1 laser-processing unit with a pulse repetition frequency of a picosecond laser from 10 to 300 kHz at a radiation energy up to 10 μJ is investigated. The combination of high-speed movements of the laser beam by the galvanoscanner system and precise positioning of the processed material increases the efficiency of laser microprocessing and expands the functional capabilities of the equipment

Biochar influence on the development of spring wheat (Triticum aestivum L.) and acidity of soddy-podzolic soil in Western Siberia

The paper purpose was to establish the effect of applying biochar obtained from various organic wastes of agriculture (cow manure, straw), woodworking (pine sawdust) and food industry (pine nut shell), which are typical of Western Siberia, on the morphometric characteristics of plants (using spring wheat (Triticum aestivum L.) as the example) and the soddy-podzolic soil properties. The assessment of biochar influence was performed by a series of vegetation experiments using climatic chambers. As a result, it was found that the introduction of all the noted biochar types into the soil layer leads to a significant (p < 0.05) increase in the morphometric characteristics of spring wheat. For example, when applying the straw biochar to the soil, it results in growing the plant height to the node by 19%, while the number of leaves increased by 8% compared to the control variant. The introduction of biochar from manure leads to the increased length of the spring wheat root by 35%. Moreover, straw and manure biochars contribute to the reduction of soil acidity (increase in pH values from 7.1 to 7.4 and 7.8, respectively). The results of the comprehensive analysis indicate that the agronomic advantages of application of biochars obtained from wheat straw and cattle manure are better compared to biochars from pine sawdust and pine nut shells, which is due to higher concentration of nutrients and substances with alkaline reaction (carbonates and oxides) in the former. The results obtained are useful from the point of view of assessing the environmental risks when applying biochar ameliorants in soils typical of the boreal bioclimatic zone. Subsequent experiments, including studies of the joint application of biochars and fertilizers to the soil, will make it possible to develop recommendations for applying the thermal conversion technology for recycling the regional organic waste into ameliorants that improve soil quality and increase its fertility

PARAMETERS OPTIMIZATION OF HIGH FREQUENCY ULTRASONIC SYSTEM FOR WIRE BONDING

Mathematical equations for resonant frequency and impedance of ultrasonic transducer for wire bonding were proposed. Clamping optimization of bonding tool was determined due to modelling of resonant frequency and impedance for standard and high frequency ultrasonic vibrations in ultrasonic system. It was shown that proposed technique gives good fit to the experimental data

Obtaining raised density connections by thermosonic microwelding in 3D integrated microcircuits

The authors consider the processes of obtaining raised density microwelded connections in 3D-integrated microcircuits by the thermosonic microwelding. The processes include the use of the raised frequencies of ultrasound, application of the microinstrument with a thinning of the working end and precision devices for ball formation, which provide reproducibility of connections quality. At a small step of contact pads, the use of a wire of small diameter (not more than 25 µm) is necessary for devices with a multilevel arrangement of leads and chess arrangement of contact pads on the chip, providing the maximum length of the formed crosspieces does not exceed 4—5 mm

Modeling and Control of the Parameters of Ultrasonic Transducer for Connecting Wire Outputs

The methods of modelling and control parameters of the ultrasonic piezoelectric transducers used for wire bonding in the electronic devices are investigated. It is established, that resonance frequencies of ultrasonic transducer may be with different mechanical oscillation modes. It was found that the matching of the piezoelectric driver and the horn in the mode of longitudinal mechanical vibrations at the resonance frequency helps to achieve the maximum quality of the wire bonding. Technological tests carried out confirm this statement

Regenerative systems of heating for heating furnaces of rolled and blacksmith’s productions (history of development, theory and practice)

There is presented the review of constructions of the heating furnaces regenerative heating systems. The calculated analysis of different factors influence on air heating temperature and hydraulic resistance of checker is carried out with the help of the mathematical model. There is given the construction of chamber furnace with checkers from corundum balls for heating of titanium alloys, which is incorporated in VSMPO

IGOFS Indik. Teilprojekt 7: Pelagische Prozesse und Partikelfluss in der Arabischen See unter besonderer Beruecksichtigung der Bedeutung autotropher Kalkbildner und des Mesozooplanktons Schlussbericht

As part of the German Indian Ocean Project biological, chemical and hydrographical measurements were carried out in the context to investigate the seasonal evolution of biogeochemcial processes with the upswing of the SW monsoon in the Arabian Sea in 1997. Planktological investigations were carried out along a filament from his origin at the coastal upwelling off Oman till his dispersal in the open ocean. Therefore a satellite tracked drifting array with a sediment trap below the productive zone was deployed in this freshly upwelled water and followed for 19 days. During this time hydrographic measurements and extensive water-column sampling has been carried out for the determination of the physical properties and planktological bulk parameters. The results include data of the biochemical level on parameters which were designed for the documentation of nutrient conditions, biological stock parameters, fluxes in the epipelagial and the export production as well as primary production and zooplankton grazing rate. The most interesting results established form this investigation show that the filament is characterised by both high dynamic and heterogeneous systems with a combination of succession and advection. The composition of phytoplankton and zooplankton population as well as the primary production and grazing rate show a distinct variability along the filament. The model for phytoplankton aggregation which simulated the biological interactions for two sites in the Arabian Sea showed quite good agreement with the data that have been measured during the process study. The administration and development of the Ggerman JGOFS databank initialised in frame of this project take place under national and international co-operation. The results obtained during this study will be adopted to the national and international data syntheses and will contribute to the JGOFS goal to better understand the biogeochemical processes with varying temporal and spatial conditions in the Arabian Sea and to find out whether the western Indian Ocean is a sink or a source for carbon in the global carbon cycle. (orig.)SIGLEAvailable from TIB Hannover: DtF QN182,15) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman