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The paper aims to evaluate mechanisms for silicon overfilling including volume expansion of silicon on solidification for composite silicon/silicon carbide (SiC) objects generated using post‐process infiltration of selective laser sintered (SLS) SiC preforms.

Overfilling was characterized through geometrical means and microscopy, and results were used for further study and discussion of overfilling mechanisms.

Silicon overfilling in silicon infiltrated SLS SiC parts is attributed primarily to its infiltrant silicon volume expansion on solidification. Si/SiC composites were found to be thermally stable with good material bonding.

Silicon as an infiltrant is unusual as it expands on solidification, whereas most infiltrants contract. Overfilling during infiltration of SLS porous performs is therefore not considered to be prevalent.

This paper provides an examination of the value of silicon as an infiltrant material for SLS SiC preforms. Various mechanisms are presented for volume change during post‐process infiltration of indirect SLS non‐metallic performs.

Silicon sensors are semiconductor devices which transform a physical effect (such as pressure, acceleration, flux) into electrical effects (resistance, capacitance variation). Fabrication of these silicon sensors requires very precise control of the silicon micromachining. Some silicon foundries have adapted their experience in integrated circuit manufacturing to silicon sensor production and thus have reduced the costs and dimensions of the silicon sensors. Standard thick film technology has brought versatility to silicon sensor technology. Silicon sensors mounted on a ceramic substrate give fast development, high performance and low cost to OEMs. An alternative solution is the integrated silicon sensor including sensor and circuitry on the same silicon chip. This has been developed for specific applications.

Small firms, which represent much of the Silicon Valley region, tend to experience losses due to their small scale, small customer base and lack of diversification. The authors study the impact of accounting conservatism and losses on firm value and as such this study is an appropriate addition to this growing field of financial management.

The authors use methodology developed in prior literature to examine Silicon Valley and non-Silicon Valley firms' and their behavior when facing losses and the factors, which might play a role in their valuation. The authors focus particularly on earnings and accounting conservatism. Accounting conservatism captures how fast firms record losses relative to gains. The faster losses are recognized than gains the more accounting conservatism is exhibited. The authors examine the seemingly unrelated estimation of differences in means for our independent variables of interest across the two samples of Silicon Valley and non-Silicon Valley firms, both earnings and accounting conservatism. The authors use matched sample analysis of these firms based on four digit SIC code, size and date. In robustness, the authors run a more in-depth propensity score matched sample analysis.

The authors document that market values of Silicon Valley firms with accounting losses are affected less by negative earnings than other firms with accounting losses in the United States outside of the Silicon Valley region, noting the “lose big, win bigger” sentiment of Silicon Valley. Additionally, the authors document that accounting conservatism does play a role in influencing valuations of companies with accounting losses both in Silicon Valley and the rest of the United States, marginally more for Silicon Valley firms.

This study would be of interest to fund managers who need to consider smaller firms for inclusion in their portfolios. A lot of small firms have experienced losses ever since going public, especially Silicon Valley start-up firms.

The purpose of this paper is to examine how entrepreneurship culture affects start-up and venture capital co-evolution during the early evolution of an entrepreneurial ecosystem (EE) and its ability to foster the emergence of ambitious entrepreneurship as an outcome of its activity. Unlike studies that capture entrepreneurship culture at the national level, this study focusses specifically on the culture of venture capital-financed entrepreneurship and understanding its implications to the development of venture capital markets and successful firm-level outcomes within ecosystems.

Relying on EE and organisational imprinting theory, this study specifies characteristics of venture capital-financed entrepreneurship of Silicon Valley to illustrate the American way of building start-ups and examine whether they have as imprints affected to the entrepreneurship culture and start-up and venture capital co-evolution in Finland during the early evolution of its EE between 1980 and 1997.

The results illustrate venture capital-financed entrepreneurship culture as a specific example of entrepreneurship culture beneath the national level that can vary across geographies like the findings concerning Finland demonstrate. The findings show that this specific culture matters through having an impact on the structural evolution and performance of EEs and on the ways how they deliver or fail to deliver benefits to entrepreneurs.

The results show that venture capital-financed entrepreneurship and the emergence of success stories as outcomes of start-up and venture capital co-evolution within an EE are connected to a specific type of entrepreneurship culture. This paper also contributes to the literature by connecting the fundamentals of organisational imprinting to EE research.

Much progress has been made in the field of corrosion technology in the last few years and many new corrosion‐resisting materials have been developed, including improved types of plastics and metals such as zirconium, titanium and tantalum. Plastics are finding extensive use as lining materials for chemical plant operating at moderate temperatures, but the poor thermal conductivity of most plastics makes them unsuitable for the transfer of heat. The recently developed metals and their alloys are extremely expensive to produce and fabricate and, so far, their use has been confined to certain specialised applications, although full‐scale production of zirconium is being carried out in America, mainly because of the low capacity of the metal for absorbing thermal neutrons. At the moment, however, these metals, because of their high cost, cannot compete commercially on a large scale with the older well‐established corrosion‐resisting alloys such as the high‐silicon iron alloys. The excellent corrosion resistance of the high‐silicon iron alloys, even at high temperatures, and their high thermal conductivity have established them as almost standard alloys for acid concentration and cooling plant construction. The following article outlines their composition and properties.

Tabbing and stringing are the critical process for crystalline silicon solar module production. Because of the mismatch of the thermal expansion coefficients between silicon and metal, phenomenon of cell bowing, microcracks formation or cell breakage emerge during the soldering process. The purpose of this paper is to investigate the effect of soldering on crystalline silicon solar cells and module, and reveal soldering law so as to decrease the breakage rates and improve reliability for crystalline silicon solar module.

A microscopic model of the soldering process is developed by the study of the crystalline silicon solar cell soldering process in this work. And the defects caused by soldering were analyzed systematically.

The defects caused by soldering are analyzed systematically. The optimal soldering conditions are derived for the crystalline silicon solar module.

The quality criterion of soldering for crystalline silicon solar module is built for the first time. The optimal soldering conditions are derived for the crystalline silicon solar module. This study provides insights into solder interconnection reliability in the photovoltaic (PV) industry.

Experts claim over 50% of sensor applications are currently served by silicon‐sensor technology.

To fabricate submicrometer thin membrane of silicon nitride and silicon dioxide over an anisotropically etched cavity in (100) silicon.

PECVD of silicon dioxide and Silcion nitride layers of compatible thicknesses followed by thermal annealing in nitrogen ambients at 1,000°C for 30 min, leads to stable membrane formation. Anisotropic etching of (100) silicon below the membrane through channels on the sides has been used with controlled cavity dimensions.

Lateral front side etching through channels slows down etching rate drastically. The etching mechanism has been discussed with experimental details.

Vacuum sealed cavity membranes can be realised for micro sensor applications.

The process is new and feasible for micro sensor technologies.

The Center for Industrial Research (SI), the University of Oslo (UiO) and a group of Norwegian companies have collaborated between 1990 and 1992 in the research programme ‘Industrial Microelectronics’ with a total cost of 30 MNOK. The programme was sponsored by the Norwegian Scientific and Industrial Research Council (NTNF) as one of the twin programmes constituting a national research initiative in microelectronics. The motivation for the programme is the recognition of microelectronics as a key technology commanding the performance and market success of many of the electronics systems from the Norwegian electronics industry towards the year 2000. The main objective is to stimulate industrial innovation by developing, transferring and exploiting knowledge and methods based upon advanced microelectronics. Focused activities are silicon sensor technology, combined analogue/digital design of application‐specific integrated circuits, large scale instrumentation, sensor packaging and thermal management of electronic systems. SI is focusing on applied research, UiO on education, and collaborating Norwegian companies are using the results in their own R&D projects. It is anticipated that the research results will be fully industrialised within 3–5 years. The programme is co‐ordinated with other Norwegian government‐sponsored research activities as well as European research programmes based on microelectronics. The programme is organised in projects and monitored with a set of milestones strongly indicating the achievement of successful industrial innovation, research results of international standing and high‐quality education of key personnel for the industry. Several successful examples of the research results are highlighted: Design and process methodology for double‐sided microstrip silicon radiation sensors for detection of high energy elementary particles, silicon‐to‐silicon and silicon‐to‐thin film anodic bonding processes for sensor fabrication, combined analogue/digital application‐specific integrated circuits for front‐end instrumentation applications, packaging of radiation sensors and thermal management of electronic systems by evaporation cooling. It is concluded that the programme has successfully achieved results in harmony with the objective.

Silver‐glass die attach materials represent a significant advance in silicon packaging technology and are expected to displace gold‐silicon eutectic bonding as the preferred method of die attachment for high reliability applications. In this paper the rle of the glass in the adhesion mechanism of silver‐glass to gold and chromium/gold backed die has been determined using thermal analysis and X‐ray diffraction in addition to scanning electron microscopy and electron probe microanalysis of the sintered film. An adhesion mechanism is proposed in which the glass of the silver‐glass system migrates to the die interface during the firing cycle and chemically bonds to the silicon which is present at the surface of the gold‐silicon eutectic. Adhesion between the die back and the silver of the die attach material is by means of a simple mechanical bond between ‘fingers’ of glass and the sintered silver matrix. Thermodynamic and kinetic considerations suggest that insufficient silicon dioxide may be formed using chromium/gold backed die for acceptable adhesion. Processing changes are proposed which resolve this adhesion problem.