Analytical Transient Responses and Gain-Bandwidth Products of Low-Dimensional High-Gain Photodetectors.

Low-dimensional photodetectors, in particular those in photoconductive mode, often have extraordinarily high photogain. However, high gain always comes along with a slow frequency response. The gain-bandwidth product (GBP) is a figure of merit to evaluate the performance of a photodetector.

Toward Defect-Free Doping by Self-Assembled Molecular Monolayers: The Evolution of Interstitial Carbon-Related Defects in Phosphorus-Doped Silicon.

Self-assembled molecular monolayer (SAMM) doping on semiconductors has been widely appraised for its advantages of doping nanoelectronic devices for applications in the complementary metal-oxide-semiconductor transistor (CMOS) industry. However, defects introduced by SAMM-doping will limit the performance of the devices. Previously, we have found that SAMM-doping can bring carbon impurities into the silicon substrate and these unwanted carbon impurities can deactivate phosphorus dopants by forming an interstitial carbon (C)-substitutional phosphorus (C-P) complex.

Dynamics of Charge Carriers in Silicon Nanowire Photoconductors Revealed by Photo Hall Effect Measurements.

Photoconductors have extraordinarily high gain in quantum efficiency, but the origin of the gain has remained in dispute for decades. In this work, we employ photo Hall effect to reveal the gain mechanisms by probing the dynamics of photogenerated charge carriers in silicon nanowire photoconductors. The results reveal that a large number of photogenerated minority electrons are localized in the surface depletion region and surface trap states.

Deep level transient spectroscopic investigation of phosphorus-doped silicon by self-assembled molecular monolayers.

It is known that self-assembled molecular monolayer doping technique has the advantages of forming ultra-shallow junctions and introducing minimal defects in semiconductors. In this paper, we report however the formation of carbon-related defects in the molecular monolayer-doped silicon as detected by deep-level transient spectroscopy and low-temperature Hall measurements. The molecular monolayer doping process is performed by modifying silicon substrate with phosphorus-containing molecules and annealing at high temperature.

Nanoscale Nitrogen Doping in Silicon by Self-Assembled Monolayers.

This Report presents a nitrogen-doping method by chemically forming self-assembled monolayers on silicon. Van der Pauw technique, secondary-ion mass spectroscopy and low temperature Hall effect measurements are employed to characterize the nitrogen dopants. The experimental data show that the diffusion coefficient of nitrogen dopants is 3.