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Future generations of power converters must be miniaturized to power future electronic devices that are getting smaller and smarter. Monolithic integration is an ideal approach toward compact, efficient, and low-cost converters. This letter addresses two technology gaps in packaging technology and integrated inductor technology using the so-called power interposer technology (PIT). We implement a step-down power converter to demonstrate PIT. The converter uses two GaN FETs, capacitors, and a gate driver stacked on a 0.28-mm-thick silicon die that hosts a 3-D substrate-embedded toroidal microinductor. The converter switches 22 MHz in zero-voltage-switching mode, achieving a peak efficiency of 83% at the full load of 1 W. PIT has shown unique technology advantages for future generations of integrated power converters, including high power density, low profile, superior thermal performance, scalability, and heterogeneous integration. Furthermore, PIT holds great commercial potential for high-power-density integrated power converters.

Miniaturization of power supplies is required for future intelligent electronic systems, e.g., Internet-of-Things devices. Inductors play an essential role, and they are by far the most bulky and expensive components in power supplies. This paper presents a miniaturized microelectromechanical system (MEMS) inductor and its performance in a very high-frequency (VHF) power converter. The MEMS inductor is a silicon-embedded air-core toroidal inductor, and it is constructed with through-silicon vias, suspended copper windings, silicon fixtures, and a silicon support die. The air-core inductors outperform the silicon-core inductors with higher quality factor at higher frequency. This is verified by small-signal measurements. A 20-turn air-core inductor achieved an inductance of 44.6 nH and a quality factor of 13.3 at 33 MHz, while a silicon-core inductor with the same geometry has a quality factor of 9 at 20 MHz. A dc–dc class-E boost converter is designed and implemented using the fabricated MEMS air-core inductor and a high-performance 65-V gallium nitride field-effect transistor. The VHF converter achieved a peak efficiency of 78% at an input voltage of 6.5 $\text{V}_{\mathrm {DC}}$ . The MEMS inductor can carry 1-A root-mean-square ac current at 33 MHz and delivers 10.5 W to the output.

Efficient adhesion of gold thin films on dielectric or semiconductor substrates is essential in applications and research within plasmonics, metamaterials, 2D materials, and nanoelectronics. As a consequence of the relentless downscaling in nanoscience and technology, the thicknesses of adhesion layer and overlayer have reached tens of nanometers, and it is unclear if our current understanding is sufficient. In this report, we investigated how Cr and Ti adhesion layers influence the nanostructure of 2–20 nm thin Au films by means of high-resolution electron microscopy, complemented with atomic force microscopy and X-ray photoelectron spectroscopy. Pure Au films were compared to Ti/Au and Cr/Au bilayer systems. Both Ti and Cr had a striking impact on grain size and crystal orientation of the Au overlayer, which we interpret as the adhesion layer-enhanced wetting of Au and the formation of chemical bonds between the layers. Ti formed a uniform layer under the Au overlayer. Cr interdiffused with the Au layer forming a Cr–Au alloy. The crystal orientation of the Au layers was mainly [111] for all thin-film systems. The results showed that both adhesion layers were partially oxidized, and oxidation sources were scrutinized and found. A difference in bilayer electrical resistivity between Ti/Au and Cr/Au systems was measured and compared. On the basis of these results, a revised and more detailed adhesion layer model for both Ti/Au and Cr/Au systems was proposed. Finally, the implications of the results were analyzed, and recommendations for the selection of adhesion layers for nano-optics and nanoelectronics applications are presented.

High frequency anodizing of friction stir processed Al-TiO2 surface composites was investigated. The effect of anodizing parameters on the structure and morphology of the anodic layer including the incorporation of the TiO2 particles into the anodic layer is studied. Anodizing process was carried out using a high frequency pulse and pulse reverse pulse technique at a fixed frequency in a sulfuric acid bath. The structure of the composites and the anodized layer was studied using scanning and transmission electron microscopy. The pulse reverse pulse anodizing technique, using a negative potential on the low voltage cycle, showed extensive pore branching and pore generation at the TiO2 particle-anodic alumina matrix interface. However, the pulse anodizing technique using zero potential during the low voltage cycle showed no such features in the pore morphology, but only entrapment of TiO2 particles into the anodic alumina. Lower electrical resistance of the TiO2 arising from oxygen defects, combined with applied negative potential during the low voltage cycle, are found to be responsible for the observed morphological features in the anodic alumina.

Compliance with new legislation in Europe and United States requires retrofitting of scrubbing technology on a large number of existing waste‐to‐energy plants to control emissions of acid gases, dioxins/furans and heavy metals, especially mercury.This paper describes the gas suspension absorber (GSA) dry scrubbing technology developed by FLS miljø a/s, Denmark. GSA is a new generation of the semi‐dry technology utilizing a circulating fluidized bed as absorber for acid gases, dioxin and heavy metals. The paper describes the GSA technology and focuses on the GSA as retrofit technology for waste‐to‐energy plants. The advantages of retrofitting the GSA upstream of an existing electrostatic precipitator are highlighted.A description of the operating experience with GSA technology for waste‐to‐energy plants and performance test results for particulate, acid gases, dioxins and mercury removal from several European waste‐to‐energy plants is given in this paper.

The first synthesis of a combinatorial library using double combinatorial chemistryis presented. Coupling of unprotected Fmoc-tyrosine to the solid support was followed by Mitsunobu O-alkylation. Introduction of a diacid linker yields a system in which the double combinatorial step can be demonstrated. The resulting library of model compounds was verified by LC-MS analysis.

Objectives– To assess the feasibility of a randomised trial of ovarian cancer screening by vaginal ultrasonography.Setting– A population based study, recruiting a random sample of the female population aged 46 to 65 years living in Copenhagen, Denmark.Design– Randomised controlled trial allocating 50% to the study group having vaginal ultrasonography, and 50% to the control group having no examination, (a) Acceptability of the study was evaluated by the proportion of eligible women willing to participate in the study, (b) The false positive rate was evaluated as the proportion of women without ovarian cancer referred for an operation because of abnormal ovaries detected by ultrasonography.Results– 950 (64–3%) of the 1477 eligible women participated in the study. At the first scan abnormal ovaries were detected in 54 of 435 women (12%), significantly more frequently among younger women. Nine women were referred for an operation because of abnormal findings in the ovaries, giving a false positive rate of 2%Ovarian size and morphology found at operation corresponded with those at ultrasonography; none of them was malignant.Conclusions– A randomised controlled trial of ovarian cancer screening using vaginal ultrasonography seems acceptable in the general population. The rate of abnormal ovaries at ultrasonography with the cut offs used in this study was quite high. Such a study is, therefore, feasible, but it is proposed that it is carried out in an older age group (50–64 years) and that the cut offs used for ovarian size and morphology are re-evaluated. Second line tests, such as colour Doppler flow, should be considered in order to reduce the false positive rate.

We report a novel combination of AFM lithography and laser direct writing on hydrogen-passivated amorphous silicon surfaces to fabricate combined silicon milli-, micro- and nanostructures. Selective oxidation is performed by focusing a laser beam (λ=458 nm) on a hydrogen-terminated silicon surface, forming the millimetre-size contact pads for connection of nanometre-scale patterns. The nanostructures are made by electric-field-enhanced oxidation using a contact mode AFM equipped with a metal-coated tip. Both techniques are based on selective oxidation of hydrogen-passivated amorphous silicon, where the oxide is used as an etch mask in a single etch step. The lithographic process has also been demonstrated using a reflection mode scanning near-field optical microscope with an uncoated fiber probe.

This study focuses on the development of a fluorocarbon-free directional silicon etching process, called CORE (Clear, Oxidize, Remove, and Etch) in which a switching sequence of SF6 and O2 is operated at room temperature. This distinguishes it from the old-fashioned room temperature and cryogenic mixed RIE processes as CORE enables a higher selectivity, creates pattern independency of etching profiles and works excellent at room temperature. The CORE process resembles the well-known SF6-based Bosch process, but the usual C4F8 inhibitor is replaced by O2 oxidation with self-limiting characteristics. Therefore the CORE result is similar to Bosch, however has the advantage of preventing the pile-up of fluorocarbon deposits at the topside of deep-etched or nano-sized features. At the same time, process drift is minimized as the reactor wall is staying perfectly clean. The CORE process has shown an excellent performance in high aspect ratio (3D) nanoscale structures with an accurate and controllable etch rate between 1 and 50 nm min[?]1 (and SiO2-selectivity of ca. 35) using the etch-tool in the RIE-mode. By adding the ICP source (DRIE-mode), a directional etch rate up to 1 um min[?]1 (at 50 sccm SF6 flow) and selectivity >200 for SiO2 is possible.

This study focuses on the development of a fluorocarbon-free directional silicon etching process, called CORE (Clear, Oxidize, Remove, and Etch) in which a switching sequence of SF6and O2is operated at room temperature. This distinguishes it from the old-fashioned room temperature and cryogenic mixed RIE processes as CORE enables a higher selectivity, creates pattern independency of etching profiles and works excellent at room temperature. The CORE process resembles the well-known SF6-based Bosch process, but the usual C4F8inhibitor is replaced by O2oxidation with self-limiting characteristics. Therefore the CORE result is similar to Bosch, however has the advantage of preventing the pile-up of fluorocarbon deposits at the topside of deep-etched or nano-sized features. At the same time, process drift is minimized as the reactor wall is staying perfectly clean. The CORE process has shown an excellent performance in high aspect ratio (3D) nanoscale structures with an accurate and controllable etch rate between 1 and 50 nm min−1(and SiO2-selectivity of ca. 35) using the etch-tool in the RIE-mode. By adding the ICP source (DRIE-mode), a directional etch rate up to 1 μm min−1(at 50 sccm SF6flow) and selectivity >200 for SiO2is possible.

We present a case of interstitial pregnancy causing uterine cornual rupture during induction of prostaglandin midtrimester abortion. As the clinical and ultrasonographic diagnosis of advanced ectopic gcstation may be difficult, the possibility of ectopic pregnancy should be considered in cases of unsuccessful attempts of induced abortion.

A prospective series of 90 consecutive pregnancies (70 singleton, 16 twin and 4 triplet pregnancies) resulting in births of 114 infants after in vitro fertilisation (IVF) at Rigshospitalet were compared to a control group of pregnancies and deliveries in 70 non-IVF infertility patients with singleton pregnancies and 20 women with normal fertility with twin (n=16) or triplet (n=4) pregnancies. No differences in the incidence of third trimester pregnancy complications, abnormal fetal karyotypes or malformations were found. The number of women with spontaneous onset of labor and the gestational age at delivery were similar in the IVF and control groups. In singleton deliveries, the birth weight was lower (p<0.025) in the IVF group (median 3145 g, range 8904300 g) than in the control group (3399 g, 2592-4850 g), whereas in multiple gestation similar birth weights were found in the IVF and control groups. We conclude that the birth weight in singleton deliveries after IVF is lower than the birth weight in infertility patients treated differently. The cause of this difference remains obscure.

High frequency anodizing of friction stir processed Al-TiO2surface composites was investigated. The effect of anodizing parameters on the structure and morphology of the anodic layer including the incorporation of the TiO2particles into the anodic layer is studied. Anodizing process was carried out using a high frequency pulse and pulse reverse pulse technique at a fixed frequency in a sulfuric acid bath. The structure of the composites and the anodized layer was studied using scanning and transmission electron microscopy. The pulse reverse pulse anodizing technique, using a negative potential on the low voltage cycle, showed extensive pore branching and pore generation at the TiO2particle-anodic alumina matrix interface. However, the pulse anodizing technique using zero potential during the low voltage cycle showed no such features in the pore morphology, but only entrapment of TiO2particles into the anodic alumina. Lower electrical resistance of the TiO2arising from oxygen defects, combined with applied negative potential during the low voltage cycle, are found to be responsible for the observed morphological features in the anodic alumina.