We report resistivity measurements from 0.03 to 10 K in a dilute high mobility 2D electron system. Using an undoped GaAs/AlGaAs heterojunction in a gated field-effect transistor geometry, a wide range of densities, 0.16 x 10(10) to 7.5 x 10(10) cm(-2), are explored. For high densities, the results are quantitatively shown to be due to scattering by acoustic phonons and impurities. In an interme...

We review the current status of heterojunction design for combinations of organic semiconductor materials, given its central role in affecting the device performance for electronic devices and solar cell applications. We provide an emphasis on recent progress towards the rational design of heterojunctions that may lead to higher performance of charge separation and mobility. We also play partic...

A novel nc-Si/c-Si heterojunction MOSFETs pressure sensor is proposed in this paper, with four p-MOSFETs with nc-Si/c-Si heterojunction as source and drain. The four p-MOSFETs are designed and fabricated on a square silicon membrane by CMOS process and MEMS technology where channel resistances of the four nc-Si/c-Si heterojunction MOSFETs form a Wheatstone bridge. When the additional pressure i...

A novel few-layer MoS2/SiO2/Si heterojunction is fabricated via DC magnetron sputtering technique, and Pd nanoparticles are further synthesized on the device surface. The results demonstrate that the fabricated sensor exhibits highly enhanced responses to H2 at room temperature due to the decoration of Pd nanoparticles. For example, the Pd-decorated MoS2/SiO2/Si heterojunction shows an excellen...

BiPO4/Bi2S3 photocatalysts were successfully synthesized by a simple two-step hydrothermal process, which involved the initial formation of BiPO4 rod and then the attachment of Bi2S3 through ion exchange. The as-synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), a...

Si heterojunction solar cells were fabricated on p-type single-crystal Si (sc-Si) substrates using phosphorus-doped Si nanocrystals (Si-NCs) embedded in SiNx (Si-NCs/SiNx) films as emitters. The Si-NCs were formed by post-annealing of silicon-rich silicon nitride films deposited by electron cyclotron resonance chemical vapor deposition. We investigate the influence of the N/Si ratio in the Si-N...

High charge-separation efficiency combined with the reduced fabrication costs associated with solution processing and the potential for implementation on flexible substrates make 'plastic' solar cells a compelling option for tomorrow's photovoltaics. Attempts to control the donor/acceptor morphology in bulk heterojunction materials as required for achieving high power-conversion efficiency have...

We have developed sensitive detection of cancer biomarker vascular endothelial growth factor (VEGF) using the p-n heterojunction comprised of p-type BiOI nanoflakes (NFs) array and n-type TiO2 nanotubes (NTs) array. Due to the unique arrayed structure and the synergy effect of photoelectrochemistry in the formed p-n junction, the synthesized configuration has superior excitation efficiency and ...

We synthesized Bi/Bi2O3 heterojunction nanoparticles at various substrate temperatures using the pulsed laser deposition (PLD) technique with a pulsed Nd:YAG laser. The Bi/Bi2O3 heterojunction nanoparticles consisted of Bi nanoparticles and Bi2O3 surface layers. The average diameter of the Bi nanoparticles and the thickness of the Bi2O3 surface layer are linearly proportional to the substrate t...

n-CdO/p-Si heterojunction diode was fabricated using sol-gel spin coating technique which is a low cost and easily scalable method for preparing of semiconductor films. The structural and morphological properties of CdO film were investigated. The X-ray diffraction (XRD) spectra indicated that the film was of polycrystalline nature. The scanning electron microscopy (SEM) images indicate that th...