Ultrathin GeSn p-channel MOSFETs grown directly on Si(111) substrate using solid phase epitaxy

Ultrathin GeSn layers with a thickness of 5.5 nm are fabricated on a Si(111) substrate by solid phase epitaxy (SPE) of amorphous GeSn layers with Sn concentrations up to 6.7%. We demonstrate well-behaved depletion-mode operation of GeSn p-channel metal–oxide–semiconductor field-effect transistors (pMOSFETs) with an on/off ratio of more than 1000 owing to the ultrathin GeSn channel layer (5.5 nm). It is found that the on current increases significantly with increasing Sn concentration at the same gate overdrive, attributed to an increasing substitutional Sn incorporation in Ge. The GeSn (6.7%) layer sample shows approximately 90% enhancement in hole mobility in comparison with a pure Ge channel on Si.status: publishe

Optical study of strained double Ge/Si quantum dot layers

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Enhancement of up-conversion efficiency by combining rare earth-doped phosphors with PbS quantum dots

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Water Stress Assessment of Cork Oak Leaves and Maritime Pine Needles Based on LIF Spectra

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Optical study of strained double Ge/Si quantum dot layers

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Photoluminescence and Raman study of a tensilely strained Si type-II quantum well on a relaxed SiGe graded buffer

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Photoluminescence and electrical study of fluctuating potentials in Cu2ZnSnS4-based thin films

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Interplay between relaxation and Sn segregation during thermal annealing of GeSn strained layers

© 2016 Author(s). The effect of thermal annealing on epitaxial GeSn (6.5% Sn) strained layers grown on Ge-buffered Si(100) wafers has been investigated using Rutherford backscattering spectrometry and X-ray diffraction to unambiguously determine the Sn substitutional content as well as the elastic strain in the layers. Vacuum annealing at temperatures below 400 °C for 20 min has no noticeable effect on the strain in the epitaxial layers. Once the temperature was raised above 400 °C, however, relaxation of the layer sets in and the GeSn layer has essentially completely relaxed following a 20 min anneal at 650 °C. Using Rutherford backscattering and channelling spectrometry to provide compositional information as a function of depth enables one to monitor the effect of the thermal anneal on the Sn distribution throughout the layer, and also to directly extract their substitutional fraction (i.e., their solubility in the lattice). The results obtained show that when the relaxation initially sets in both the Ge and the Sn remain firmly bound in substitutional lattice sites and it is only around 600 °C, and after substantial relaxation has taken place, that Sn is finally expelled from lattice sites and diffuses to the surface of the sample.status: publishe

Experimental Evidence and Modified Growth Model of Alloying in InxGa1-xAs Nanowires

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Ultrathin GeSn p-channel MOSFETs grown directly on Si(111) substrate using solid phase epitaxy

Ultrathin GeSn layers with a thickness of 5.5 nm are fabricated on a Si(111) substrate by solid phase epitaxy (SPE) of amorphous GeSn layers with Sn concentrations up to 6.7%. We demonstrate well-behaved depletion-mode operation of GeSn p-channel metal–oxide–semiconductor field-effect transistors (pMOSFETs) with an on/off ratio of more than 1000 owing to the ultrathin GeSn channel layer (5.5 nm). It is found that the on current increases significantly with increasing Sn concentration at the same gate overdrive, attributed to an increasing substitutional Sn incorporation in Ge. The GeSn (6.7%) layer sample shows approximately 90% enhancement in hole mobility in comparison with a pure Ge channel on Si.status: publishe