We have grown thin Ge films that were fully strain relaxed and had smooth surfaces on Si(001) surfaces without buffer layers by ultrahigh vacuum chemical vapor deposition. The procedure consists of layer-by-layer Ge growth with hydrogen-surfactant mediation and high-temperature (∼700 °C) post-growth annealing for strain relaxation. The key step is the formation of a thin (less than 1 nm thick) capping Si or SiGe layer on the layered Ge film before the annealing. This capping layer effectively suppresses clustering of Ge during the annealing, even at high temperatures. Cross-sectional transmission electron microscopy of annealed samples having a 20-nm-thick Ge film clearly revealed a periodic array of 90° full-edge dislocations with a Burgers vector of a/2〈110〉 type confined at the Ge/Si interface. This dislocation structure leads to efficient strain relaxation in the Ge film, which was also confirmed by x-ray diffraction measurement.

We have fabricated Cu-based micropatterns in an ambient environment using femtosecond laser direct writing to reduce a glyoxylic acid Cu complex spin-coated onto a glass substrate. To do this, we scanned a train of focused femtosecond laser pulses over the complex film in air, following which the non-irradiated complex was removed by rinsing the substrates with ethanol. A minimum line width of 6.1 µm was obtained at a laser-pulse energy of 0.156 nJ and scanning speeds of 500 and 1000 µm/s. This line width is significantly smaller than that obtained in previous work using a CO2 laser. In addition, the lines are electrically conducting. However, the minimum resistivity of the line pattern was 2.43 × 10−6 Ω·m, which is ~10 times greater than that of the pattern formed using the CO2 laser. An X-ray diffraction analysis suggests that the balance between reduction and re-oxidation of the glyoxylic acid Cu complex determines the nature of the highly reduced Cu patterns in the ambient air.

We found that the prevalence of gestational hypertension, lower placental weight, and the presence of placental infarctions were all independently associated with the risk of LGA. Placental abnormalities may be etiologically important for LGA risk, though further research is necessary.

We have developed a new interconnect technique using a low-k (εt,=2.5) organic interlayer (fluorinated amorphous carbon: a-C:F) and a low-resistivity metal line (copper). The new technique attains a duction in both the capacitance of the interlayer and the resistance of the metal line. We found that a-C:F on Cu reduces reflection to 10% for Kr-F line lithography. However, a-C:F cannot act as a protection layer for oxidation even at 200°C in atmospheric ambient annealing. Cu diffusion into a-C:F is about 100 nm at the annealing temperature of 450°C. The resistivity of the Cu line is 2.3–2.4 μΩ · cm for the 0.5-μm line width. Although the leakage current of the a-C:F ILD is one order higher than that of the SiO2 ILD, electrical isolation is acceptable at < 20 V when annealing is carried out at 350°C in a vacuum.

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