High-speed light emitters integrated on silicon chips can enable novel architectures for silicon-based optoelectronics, such as on-chip optical interconnects, and silicon photonics. However, conventional light sources based on compound semiconductors face major challenges for their integration with a silicon-based platform because of their difficulty of direct growth on a silicon substrate. Here we report ultra-high-speed (100-ps response time), highly integrated graphene-based on-silicon-chip blackbody emitters in the near-infrared region including telecommunication wavelength. Their emission responses are strongly affected by the graphene contact with the substrate depending on the number of graphene layers. The ultra-high-speed emission can be understood by remote quantum thermal transport via surface polar phonons of the substrates. We demonstrated real-time optical communications, integrated two-dimensional array emitters, capped emitters operable in air, and the direct coupling of optical fibers to the emitters. These emitters can open new routes to on-Si-chip, small footprint, and high-speed emitters for highly integrated optoelectronics and silicon photonics.

Measurements of densities of excited atoms and metastables were performed in pure Ar and in mixtures of Ar and CF4 in inductively coupled plasma sustained by a high frequency (13.56 MHz) source and biased by a low frequency (500 kHz) voltage applied to the wafer supporting electrode. The measurements are made in front of the biased electrode with a goal to understand the effects of different parameters on the plasma profile and to test whether functional separation between plasma sustaining and biasing voltage is achieved. We find a very efficient separation with small or no observable effects of biasing voltage both in pure argon and in mixtures. These results have been achieved at all pressures (5–50 mTorr) and were confirmed by additional microwave measurements of electron density. The effect of flow rate, pressure, power, and distance from the biased electrode was studied from the spatial profiles of short lives excited states and metastable states of argon. We have also compared the profiles close to the biasing electrode, close to the coil and in extended processing chamber, and found a slight increase of metastable density close to the biasing electrode due to reduced electron quenching far from plasma source.

We have applied optical emission spectroscopy together with computerized tomography (CT) to study the transition between E and H modes in inductively coupled plasma. Measurements were performed in pure Ar and in CF4(5%)/Ar mixture in the pressure range between 5 and 300 mTorr. It was found that the radial and azimuthal CT images of the E (capacitively coupled) mode are quite different from those of the H (inductively coupled) mode. The E mode structures show clearly the presence of capacitive coupling, while the structure of the H mode corresponds to that of the predicted induced fields. The differences diminish at low pressures due to the non-local transport of electrons. The contributions of direct and stepwise excitation are separated by using two different energy levels, 2p1 and 2p9, of Ar. In addition, the measurements obtained in electronegative gas mixture with large losses of electrons of moderate and small energy show more clearly the kinetics of excitation in the two modes and the regions where high-energy electrons are produced.

To assess the effect of dienogest on recurrence of ovarian endometriomas and severity of pain after laparoscopic surgery, a retrospective study of 81 patients was performed at three institutions in Osaka, Japan. Patients had a six-month minimum follow-up after laparoscopic surgery for ovarian endometriomas performed between June 2012 and August 2014. Patients who chose to receive 2 mg dienogest daily and those who were managed expectantly postoperatively were included. Recurrence was defined as the presence of endometriomas of more than 2 cm. A visual analog scale (VAS) was used to score the intensity of pelvic pain. The cumulative recurrence rate and absolute VAS score changes between the baseline and at 6, 12, 18 and 24 months after the start of administration were evaluated in both groups. The recurrence rate was 16.5% and 24.0% in the expectant management group at 12 and 24 months, respectively. No recurrences occurred in the dienogest treatment group. The rate of VAS score reduction was significantly higher in the dienogest than in the expectant management group. Dienogest is effective on the recurrence of ovarian endometrioma and relieving pelvic pain after laparoscopic surgery.

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