Yosuke Shimura

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Germanium-on-silicon thermo-optic phase shifters are demonstrated in the 5 μm wavelength range. Basic phase shifters require 700 mW of power for a 2π phase shift. The required power is brought down to 80 mW by complete undercut using focused ion beam. Finally an efficient thermo-optic phase shifter is demonstrated on the germanium on SOI platform. A tuning(More)
In this letter, we describe the use of a germanium-on-silicon waveguide platform to realize an arrayed waveguide grating (AWG) operating in the 5 μm wavelength range, which can be used as a wavelength multiplexer for mid-infrared (midIR) light engines or as the core element of a midIR spectrometer. Ge-on-Si waveguide losses in the range 2.5-3.5 dB/cm(More)
In this paper we discuss silicon-based photonic integrated circuit technology for applications beyond the telecommunication wavelength range. Silicon-on-insulator and germanium-on-silicon passive waveguide circuits are described, as well as the integration of III-V semiconductors, IV-VI colloidal nanoparticles and GeSn alloys on these circuits for(More)
Strained Ge p-channel FinFETs on Strain Relaxed SiGe are reported for the first time, demonstrating peak transconductance gm<sub>SAT</sub> of 1.3mS/&#x03BC;m at V<sub>DS</sub>=-0.5V and good short channel control down to 60nm gate length. Optimization of P-doping in the SiGe, optimized Si cap passivation thickness on the Ge, and improved gate wrap of the(More)
A surface-illuminated photoconductive detector based on Ge0.91Sn0.09 quantum wells with Ge barriers grown on a silicon substrate is demonstrated. Photodetection up to 2.2µm is achieved with a responsivity of 0.1 A/W for 5V bias. The spectral absorption characteristics are analyzed as a function of the GeSn/Ge heterostructure parameters. This work(More)
A one-growth step fabrication scheme for strained Ge FinFET structures has been successfully developed and implemented in a device fabrication scheme. From device point of view, the concept including two growth steps might be even more favorable. However, it requires an improvement of the pre-epi oxide removal from Si<sub>1-x</sub>Ge<sub>x</sub> surfaces.
The homogeneous broadening in Phosphorus doped Ge layers is characterized using photoluminescence spectroscopy and absorption measurements. A broadening parameter rHOM&#x003D;45meV due to carrier scattering effects was extracted leading to an estimated increase in threshold current density for Ge lasers by a factor &#x003E;4.
In this paper we elaborate on our development of silicon photonic integrated circuits operating at wavelengths beyond the telecommunication wavelength window. Silicon-on-insulator waveguide circuits up to 3.8 &#x03BC;m wavelength are demonstrated as well as germanium-on-silicon waveguide circuits operating in the 5-5 &#x03BC;m wavelength range. The(More)