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This paper is a practical and empirical investigation into the relationship and overlap between the two industrial paradigms of Lean Management and Industry 4.0. This is accomplished with an in-depth case study of a goods receipt to identify Lean wastes and accompanied by a discussion on how these wastes can be eliminated by enhancing the processes and material flows with Industry 4.0 technologies. It was found that efforts to enhance a process with Industry 4.0 Technologies should be preceded by ensuring that the process can be performed in a standardized manner. After that the study recommends improved methods of data collection which enables the effective implementation of other supporting Industry 4.0 Technologies. Denna uppsats är en praktisk och empirisk utredning av relationen och samspelet mellan de två industriella paradigmen Lean Management och Industri 4.0. Till grund för det för det ligger en utförlig fallstudie av en godsmottagning för att identifiera Lean slöserier och en tillhörande diskussion om hur dessa slöserier kan elimineras genom att förbättra arbetsprocesser och materialflöden med Industri 4.0 och tillhörande teknologier. Ur det uppdagades att åtgärder för göra processer mer effektiva med dessa Industri 4.0 teknologier bör föregås av att processen kan utföras på ett standardiserat vis. När det är säkerställt så är det denna studies rekommendation att fokusera på metoder och verktyg för insamling av data vilket blir den grund som möjliggör implementering av behjälpliga och automatiserande Industri 4.0 teknologier.

Infection with some virus types induces susceptibility to the cytotoxic effect of tumor necrosis factor alpha (TNF-alpha). To investigate whether expression of polyomavirus proteins has this effect on cells, the TNF-alpha sensitivity of C127 and L929 mouse cells transfected with viral DNA was analyzed. Expression of all three polyomavirus early proteins, the tumor (T) antigens, had no apparent effect. In contrast, middle T antigen by itself induced hypersensitivity to TNF-alpha. This effect was reversed by retransfection of the cells with DNA encoding small T antigen. Expression of this polypeptide also decreased the sensitivity of bovine papillomavirus type 1-transformed cells to TNF-alpha, showing that the protective function of the polyomavirus small T antigen was not strictly linked to a middle-T-antigen-induced event. Mouse and human TNF-alpha had the same effect on normal and transformed mouse cells, suggesting that this effect was mediated by TNF receptor 1. Consistent with this conclusion, all cell clones used in the experiments expressed TNF receptor 1 at similar levels, while we failed to detect TNF receptor 2. The amount of receptor on the cells was not influenced by binding of the ligand. Addition of TNF-alpha at cytotoxic concentrations to cells expressing middle T antigen by itself resulted in significant fragmentation of chromosomal DNA after only a few hours, indicating induction of apoptosis. Addition of the cytokine to these cells also leads to release of arachidonic acid, showing that phospholipase A2 was activated. However, production of arachidonic acid did not appear to significantly precede loss of cell viability.

Properties of the silicon/diamond interface are investigated in terms of leakage current measurements of silicon pn-junction diodes. Two different types of pre-treatment and deposition methods of polycrystalline diamond were investigated, microwave assisted plasma CVD (MPCVD) with bias pre-treatment and hot filament CVD (HFCVD). It was found that when the depletion region was in contact with the silicon/diamond interface the leakage current was increased. Generation at surface states, with a surface recombination velocity of about 9 × 106 cm s−1, was found to be the responsible mechanism in the MPCVD samples, while surface conduction was also contributing to the leakage current in the HFCVD samples. However, near ideal diode characteristics with low leakage current were obtained by introducing a thin silicon dioxide layer between the silicon and diamond.

Two combinations of oxidizing and etching agents, H2SO4:H2O2:HF and HNO3:HF, have been used to modify silicon surfaces prior to wafer bonding. The chemical oxide thickness can be adjusted between 0 and 10 Angstrom by tuning the HF content of the mixtures

The chemical stability of polycrystalline diamond subjected to common silicon device integrated circuit process steps has been investigated using Raman spectroscopy, scanning electron microscopy, I‐V, and capacitance‐voltage. Wet chemical process steps such as RCA cleaning, KOH etching, and aluminum etching were performed without significant degradation of the diamond. No contamination, as judged from electrical data, of reference metal oxide semiconductor capacitors from the diamond was seen during furnace treatments. Diamond was found to withstand annealing at 950°C without electrical degradation. Patterning of diamond was demonstrated and utilized in manufacturing of test structures. Methods have been found to protect the diamond at temperatures up to 1100°C during thermal oxidation of adjacent silicon. Capping layers consisting of silicon nitride, silicon nitride on top of chemically vapor deposited oxide and polysilicon were found to protect diamond during thermal oxidation. A silicon‐on‐diamond wafer process based on process steps investigated in this paper is proposed.

The effects of preparation of silicon surfaces in hydrofluoric acid solutions, prior to direct wafer bonding, is investigated. Surface analysis with atomic force microscopy, electron spectroscopy for chemical analysis, and estimation of the surface particle density is made. This is related to results from room temperature bonding experiments. A diluted (1–10%) solution is most favorable for hydrophobic silicon wafer bonding. The subsequent water rinse should be omitted, or performed in a careful way, to avoid particle contamination. solutions generally are not favorable for bonding. The initial room temperature bonding is attributed to the relatively weak van der Waals forces, which makes the bonding sensitive to the surface roughness and particle density. The surface chemistry appears to have a second order influence in hydrophobic bonding.

A buried conductive layer in silicon has been created using wafer bonding technique, with a cobalt interfacial layer.Co-coated silicon wafers were brought into contact with either similar or uncoated wafers at room temperature. CoSi2 wasthen formed through a solid-phase reaction, during an anneal at 700 to 900°C. A 700 A buried CoSi2-layer, with a resistivityof approximately 21 µ cm, was achieved. Good adhesion, as measured by tensile strength testing, between the wafers wasachieved. Transmission electron microscopic investigations (Co-coated wafer bonded to bare silicon) showed that thesilicide has not grown into the opposite wafer, and that an amorphous layer exists between the silicide and the siliconsurface. The presence of such a layer has been confirmed by electrical characterization.

The nozzle design for a colour ink-jet print head using Hertz's continuous ink-jet method is described. A multiple jet implementation with eight jets per colour is developed by using silicon nozzle array plates manufactured by micromachining. Three different arrays have been tested in terms of directionality and clogging. In the final design, the orifices are formed as conical piles, in order to lengthen the effective channel and to reduce the surface wetting.

The choice of surface treatment prior to silicon wafer bonding is crucial both for the reliability of the bonding process and the electrical properties of the bonded structure. In the case of silicon direct bonding for manufacturing of buried electrical junctions, the bonding step is particularly critical for accurate and reproducible results. In this work, the attraction between HF-etched surfaces and the effect of a following water rinse were investigated by studying the bonding spontaneity, velocity of the initial bonding wave, and the electrical properties of the bonded junctions. Spontaneous bonding occurred when no subsequent water rinse was made after the HF-etch, while water-rinsed wafers did bond only with the help of an applied pressure and also ended up with more voids

Effects of substrate biasing of lateral bipolar transistors (LBTs) on thin SOI have been investigated. It was found that the current gain can be increased by a factor of several decades. This effect is explained by a changed base charge condition when the substrate is biased. It can be concluded that the investigated effect enables LBTs on SOI to get higher current gain than comparable bulk devices.

The formation of etch-stop layers in silicon micromachining is important in fabricating three-dimensional structures. Etch-stop layers also are important in fabricating SOI-material with BESOI-technique. We present here an electrochemical etch stop, MIS-stop, similar to the p-n etch-stop technique, with a significant difference in that the n-type layer is formed by accumulation of electrons. Hence, the etch-stop layer contains only the bulk impurities, which positively affects further processing

A novel way to fabricate a buried etch stop layer in silicon is presented in this article. The etch stop layer is formed by nitrogen implantation and the investigations show that a dose of 1.10 17 14 N + -ions/cm 2 at 140 keV is enough to effectively stop the silicon etch reaction in an ethylenediamine-pyrocatechol-water solution. The nitrogen concentration where the etch reaction stops was estimated with secondary ion mass spectroscopy measurement to be about 2.5.10 21 ions/cm 2 , which is far below the necessary concentration for nitride formation

Experimental characteristics of ultrashallow n+p junctions manufactured by vacuum evaporation of antimony (Sb) and silicon (Si), followed by heat treatments to recrystallize the amorphous silicon, are presented. It is found that the n+p junction is located less than 300 A inside the crystalline silicon and that all Sb is redistributed within the regrown film. Comparisons with Schottky (Sb‐Si) diodes show that with a heat treatment at 900 °C, the diodes convert fully from Schottky type to n+p type. Furthermore, normally off‐type junction field‐effect transistors have been fabricated using these n+p junctions as gate junctions, and the characteristics are presented together with data concerning threshold voltage variations. Also, the subthreshold characteristics of these junction field‐effect transistors are presented. The behavior in the subthreshold region is found to be excellent.

p‐n junctions formed by vacuum evaporation of silicon on crystalline silicon have been investigated. The junctions were formed by ion implantation of 49BF+2 in the evaporated silicon films. Subsequently, an isochronal heat treatment in the range of 600–850 °C was performed and its influence on the doping distributions and corresponding diode behavior was studied. Secondary‐ion mass spectrometry was used to investigate the resulting boron distributions. A sharp decrease in the boron concentration was found at the interface for the sample annealed at 850 °C.The fabricated p‐n junctions were evaluated by measuring the current‐voltage characteristics. Comparisons were made to ordinary diffused p‐n junctions in bulk silicon. Using the current‐voltage measurements, the leakage current and the ideality factor of the diodes were extracted. The reverse currents were also measured and show a nonsaturating behavior. The resistivity of the films were investigated as a function of anneal temperature, and it was found ...

A method for silicon surface preparation prior to wafer bonding in presented. By cleaning thp wafers in a H2SO4:H2O2 mixture in which a small amount of HF is added, and then rinsing in H2O, the bon ...

This paper reports a new measurement method for extraction of sub-micrometer channel lengths in DMOS transistors. The method is based on capacitance-voltage measurements of the gate to source, gate to p-base and gate to drain capacitances. A channel length of 0.3 /spl mu/m has been measured on DMOS transistors. Numerical device simulations and small-signal capacitance simulations support the results and the measurement principle.

In this abstract a concept is presented aimed to increase the heat distribution and to reduce the thermal resistance in SOI-devices. This is realized using a combination of fusion bonding and thinning against stopping layers with deposition of poly-crystalline diamond as the buried isolator. Thus, by replacing oxide with diamond, a Silicon-on-Diamond (SOD) structure is formed. >

A novel high-voltage DMOS transistor with a low doped extended gate is presented. The device withstands 240 V in the off-state and has a specific on-resistance of 24 m/spl Omega/cm/sup 2/. The transconductance is 60 mS/mm at 3 V gate voltage. The sub-micron channel length gives small-signal high-frequency performance as f/sub T/=2.8 GHz and f/sub max/=5.8 GHz and the unilateral power gain at 900 MHz is over 15 dB. The dependence of breakdown voltage and on-resistance on gate doping level and polysilicon gate length is investigated with device simulations. It is found that the breakdown voltage is highly dependent on the gate doping level.

Summary form only given. Self-heating in Silicon-On-Insulator (SOI) devices has during the past years attracted lots of attention and is a problem that remains to be solved. It has, furthermore, been shown that in smart power devices, thick buried oxides of 3 /spl mu/m or more are desired to prevent the substrate potential to lower breakdown voltages. However, these thicker buried oxides will only aggravate the thermal limitations imposed by the buried oxide. Due to the outstanding thermal properties of diamond compared to silicon dioxide, it would consequently be advantageous if silicon dioxide could be replaced with diamond in future SOI materials. Even though it has been shown that diamond is compatible with conventional silicon processing, no MOS-transistors with thermally grown gate oxide has been manufactured up to date, due to the difficulty in protecting diamond during furnace oxidations. In this paper Silicon-On-Diamond (S-O-D) MOS-transistors with thermally grown gate oxide are presented for the first time.

A new type of DMOS transistor aimed at high voltage power amplifications in the Giga-Hertz region is integrated into a standard CMOS process. By optimising the design for high voltage and high frequency, remarkable good electrical behaviour is obtained. The frequency performance was measured to f/sub T/=4.6 GHz and f/sub MAX/=10 GHz for a device with a channel length of 0.3 /spl mu/m and a breakdown voltage V/sub BR//spl ges/60 V. For a similar device fabricated on the same chip and using the same process flow, but designed to handle voltages above 300 V, f/sub T/=1.8 GHz and f/sub MAX/=3.2 GHz were measured.

Silicon-on-Diamond (SOD) is a candidate for the next generation of SOI materials, especially for applications requiring high heat spreading capability. Undoped diamond is a highly electrically insulating material at temperatures below 600 K. Resistivities above 10/sup 13/ /spl Omega/cm (at 10 V) and breakdown fields above 10/sup 7/ V/cm have been reported. Diamond conducts heat about 10 times better than silicon and more than 1000 times better than silicon dioxide. In this paper, necessary process modifications for successful manufacturing of devices on SOD-materials are discussed and evaluated.

The initial attraction of silicon surfaces etched in aqueous and buffered HF solutions have been studied, by observing the spontaneity and velocity of the contact wave. Also, the effect of a following water rinse was investigated. The bond strengths were determined by measuring the surface energy of the bonds at room temperature. Surfaces etched in an aqueous HF solution, with no subsequent water rinse before drying and contacting, bond spontaneously. If water rinsing is performed after the etch, the spontaneity is lost and the surfaces bond only if a pressure is applied. Surfaces etched in a buffered HF solution did not bond.

The N-terminal part of the mouse polyomavirus T antigens contains a highly conserved segment (-LLELLKL-), including amino acid residues 13 to 19. The sequence motif is predicted to form alpha helix I in the DnaJ domain of the T antigens. Four mutants with conservative substitutions of amino acid residues 13 and 14 were constructed. Of the four substitutions, L13M, L13I, L13V, and L14V, only L13V resulted in a phenotypic change. In transfected mouse cells, L13V large T antigen showed a more than 100-fold-reduced viral DNA synthesis. The viral replication could not be rescued by cotransfection of the cells with DNA expressing small t antigen or a large T antigen truncated at the C terminus that would compensate for a defect in host cell stimulation. In contrast to the effect on DNA replication, the L13V substitution in large T antigen did not prevent complex formation with Hsc70 and the Rb protein. Also, the activity of the protein in transactivation of transcription from the adenovirus E2 promoter was unimpaired, showing that the transcription factor E2F was released from pRb. The L13V substitution also caused a defect in small t antigen. However, this phenotypic change was due to protein instability. In contrast, middle T antigen with the L13V substitution remained stable and functional in cellular transformation. Together, the data show that the effect of the L13V substitution did not abrogate the Hsc70 interaction of the DnaJ domain. However, it is possible that the substitution of amino acid residue 13 affected specific DnaJ functions of large T antigen.

Silicon direct bonding (SDB) between both hydrophilic and hydrophobic surfaces was studied by measuring the surface energies. Without annealing, roughly the same energies were measured for both types of surfaces. The strongest bonds were achieved for hydrophobic surfaces, annealed at 600 degrees C and above. The established mechanism for SDB, where OH groups are held responsible for the initial attraction force, cannot explain bonding between hydrophobic surfaces where almost no OH groups are present. By calculating the surface energy/mole, and comparing this to data for hydrogen bonds and van der Waals forces, a novel mechanism for SDB is proposed where the initial attraction is due to van der Waals forces.

A polysilicon gate structure for application as gate material in p-channel JFET's is presented. The structure was manufactured using solid-phase epitaxy of an evaporated antimony/amorphous—silicon layer. The fabrication process together with experimental evaluation of both diode and JFET characteristics is given. The structure shows near ideal n+p-junction behaviour and the fabricated JFET's are normally off with good values of subthreshold swing and transconductance.