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In this study, we fabricate and investigate Schottky barrier contact on n- and p-type In0.53Ga0.47As with transparent conductive oxide (TCO) that transmits light from the visible to short-wave infrared (SWIR) region. The TCO/p-In0.53Ga0.47As contact exhibits explicit rectifying behavior in current–voltage measurement, with an effective Schottky barrier height of 0.587 eV ( I– V) and 0.567 eV ( C– V). Conversely, the TCO/n-In0.53Ga0.47As exhibits the Ohmic behavior. From high-resolution transmission electron microscopy observations, we identified two types of interfacial layers between TCO and InGaAs: an In/Ga-rich InGaAs oxide layer and an In/Ga-deficient InGaAs layer. These interfacial layers may have a significant impact on the performance of the Schottky barrier contact. An ultra-thin Ni-layer insertion at the TCO/n+-InGaAs interface reduces the contact resistivity by more than an order of magnitude while maintaining high transparency. The TCO/p-InGaAs Schottky barrier contact also performs broadband light detection from the visible to SWIR region in a front-side illumination manner, which is highly promising for detecting wavelengths covering the optical communication band.

By using a transparent conductive oxide (TCO) gate for the short-wave infrared (SWIR) region, the high optical responsivity of 180 A/W at 1550 nm and the broadband photosensitivity up to 1800 nm are demonstrated in InGaAs photo field-effect transistors (photoFETs) with front-side illumination (FSI). The photoresponse of the InGaAs photoFETs through the TCO gate can be reasonably explained by the photovoltaic effect in the photoFET operation. It was found that the spectral responsivity characteristics of TCO gate InGaAs photoFETs exhibit higher and broader responsivity compared with those of the InGaAs photodiode. The TCO gate InGaAs photoFETs are the most promising architecture for a high responsivity and broadband SWIR FSI photodetector for monolithic integration with optical communication devices and Si-LSI.

We present the HEtero-Layer Lift-Off (HELLO) technique to obtain ultra thin body (UTB) Ge on insulator (GeOI) substrates. The transferred ultra thin Ge layers are characterized by the Raman spectroscopy measurements down to the thickness of ∼1 nm, observing a strong Raman intensity enhancement for high quality GeOI structure in ultra thin regime due to quantum size effect. This advanced Ge layer transfer technique enabled us to demonstrate UTB-GeOI nMOSFETs with the body thickness of only 4 nm.

We fabricated Ge-on-insulator monocrystalline nanolayers with thickness H = 1–18 nm using SiO2 substrate and studied their Raman spectra. The spectra display longitudinal optical (LO) phonon and confined acoustic phonon bands. For H

The hole Hall mobility of Si1−xGex single crystal alloys grown by the traveling liquidus-zone method has been investigated. Raman analysis of the alloys with various Ge contents show excellent compositional uniformity and high crystal quality without strain. Secondary ion mass spectrometry indicates that the B concentration is homogeneous throughout the depth of the alloys. The hole Hall mobility in alloys with a low carrier concentration of ∼1 × 1015 cm−3 shows a higher mobility compared with previous results, indicating a reduction in alloy scattering effects. These results suggest that scattering processes in alloy semiconductors should be reconsidered both experimentally and theoretically.