• EDISON SW 활용 경진대회 논문집
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• 제6회(2017년)
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• pp.424-427
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• 2017

This study investigated the effect of strain on hole mobility and hole effective mass in a p-channel rectangular nanowire with two-dimensional confinement. We obtained the valence energy band structure using the six-band k.p method and calculated the mobility and effective mass of the hole in the [100] direction taking the strain effect into account in the inversion region. The hole mobility of strained silicon was calculated using Kubo-Greenwood formalism. As a result, it showed good performance compared to relaxed silicon, but its magnitude was insignificant.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.113-114
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• 2007

Hole mobility characteristics of single surface channel and dual channel Si/SiGe structure are compared, where the former one consists of a relaxed SiGe buffer layer and a tensile strained Si layer on top, and for dual channel structure a compressively strained SiGe layer is inserted between them. Due to the difference of hole mobility enhancement factors of layers between them, hole mobility characteristics with respect to the Si cap thickness shows the opposite tend. Hole mobility increases with thicker Si cap for single channel structure, whereas it decreases with thicker Si cap for dual channel structure.

• 한국전기전자재료학회논문지
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• 제21권1호
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• pp.44-48
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• 2008

Hole mobility characteristics of two representative biaxially strained SiGe/Si structures with high Ge contents are studied, They are single channel ($Si/Si_{1-x}Ge_x/Si$ substrate) and dual channel ($Si/Si_{1-y}Ge_y/Si_{1-x}Ge_x/Si$ substrate), where the former consists of a relaxed SiGe buffer layer with 60 % Ge content and a tensile-strained Si layer on top, and for the latter, a compressively strained SiGe layer is inserted between two layers, Owing to the hole mobility performance between a relaxed SiGe film and a compressive-strained SiGe film in the single channel and the dual channel, the hole mobility behaviors of two structures with respect to the Si cap layer thickness shows the opposite trend, Hole mobility increases with thicker Si cap layer for single channel structure, whereas it decreases with thicker Si cap layer for dual channel. This hole mobility characteristics could be easily explained by a simple capacitance model.

• Transactions on Electrical and Electronic Materials
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• 제6권6호
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• pp.280-283
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• 2005

The moving photocarrier grating (MPG) technique for the determination of the carrier mobilities and the recombination lifetime of $\alpha$-Se:As films has been studied. The electron and hole drift mobility and the recombination lifetime of $\alpha$-Se films with arsenic (As) additions have been obtained from measurement of the short circuit current density $j_{sc}$ as a function of grating velocity and spatial period. The hole mobility decreases due to defect density of hole traps when x exceeds 0.003, whereas the hole mobility increases for the case of low As addition (x$\le$0.003). We have found an increase in hole drift mobility and recombination lifetime, especially when As with (x = 0.003) is added into the $\alpha$-Se film.

• 한국전기전자재료학회논문지
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• 제20권11호
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• pp.939-942
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• 2007

We investigated the characteristics of UTB-SOI pMOSFETs with SOI thickness($T_{SOI}$) ranging from 10 nm to 1 nm and evaluated the dependence of electrical characteristics on the silicon surface orientation. As a result, it is found that the subthreshold characteristics of (100)-surface UTB-SOI pMOSFETs were superior to (110)-surface. However, the hole mobility of (110)-surface were larger than that of (100)-surface. Especially, the enhancement of effective hole mobility at the effective field of 0.1 MV/cm was observed from 3-nm to 5-nm SOI thickness range.

• 한국전기전자재료학회논문지
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• 제14권8호
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• pp.675-678
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• 2001

We fabricated the organic light emittign diodes (OLEDs) with ITO/Cu-Pc/triphenyl-diamine (TPD)/TPD+tris-(8-hydroxyquinoline) aluminum (Alq$_3$)/Al. The electrical properties of Cu-Pc thin film were studied as a hole injection layer. the energy gap of Cu-Pc thin films is decreased according to the substrate heat treatment temperature increased. It could be controlled the hole mobility by changing the heat treatment condition of Cu-Pc. The emission wavelengths could be controlled by changing hole mobility and recombination zone in emission layer.

• Macromolecular Research
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• 제17권9호
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• pp.714-717
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• 2009

Hole transport copolymers consisting of 3,4-ethylenedioxythiophene (EDOT) and N-4-butylphenyl-N,N-diphenylamine (BTPA) were synthesized by oxidative coupling reaction using $FeCl_3$ as an oxidant. These copolymers showed good solubility and their thin films showed sufficient morphological stability. The copolymers showed an absorption maximum around 320 nm. Copolymers had an oxidation peak at approximately $1.03{\sim}1.14V$ versus the Ag/AgCl electrode. The hole mobility increased with increasing portion of the EDOT unit. The hole mobility of the copolymer containing 57% of the EDOT unit showed the highest mobility of $3{\times}10^{-5}cm^2/V{\cdot}s$.

• E2M - 전기 전자와 첨단 소재
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• 제9권6호
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• pp.564-571
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• 1996

We calculated the drift-velocities of electrons and holes of I $n_{0.53}$(A $l_{x}$G $a_{1-x}$ )$_{0.47}$As, which is used for semiconductor materials of high performance HBTs, along with the various doping concentrations and Al mole fractions as well as the electric fields by Monte Carlo experiment. Especially, for the valence bands the accuracy of hole-drift-velocity was improved in the consideration of intervalley scattering due to the inelastic scattering of acoustic phonon. From the results the empirical formulas of the low- and high field mobility of electrons and holes were extracted by using nonlinear least square fitting method. The accuracy of the formulas was proved by comparing the formula of low-field electron mobility as well as drift-velocity of I $n_{0.53}$ G $a_{0.47}$As and of low-field hole mobility of GaAs with the measured values, where the error was below 10%. For the high-field mobilities of electron and hole the results calculated by the formulas were very well matched with the MC experimental results except at the narrow field range where the electrons produced the velocity overshoot and the corresponding error was about 30%.0%. 30%.0%.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.795-802
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• 2012

Geminate electron-hole recombination in organic solids in the presence of a donor-acceptor heterojunction is studied by computer simulations. We analyze how the charge-pair separation probability in such systems is affected by energetic disorder of the media, anisotropy of charge-carrier mobilities, and other factors. We show that in energetically disordered systems the effect of heterojunction on the charge-pair separation probability is stronger than that in idealized systems without disorder. We also show that a mismatch between electron and hole mobilities reduces the separation probability, although in energetically disordered systems this effect is weaker compared to the case of no energetic disorder. We demonstrate that the most important factor that determines the charge-pair separation probability is the ratio of the sum of electron and hole mobilities to the rate constant of recombination reaction. We also consider systems with mobility anisotropy and calculate the electric field dependence of the charge-pair separation probability for all possible orientations of high-mobility axes in the donor and acceptor phases. We theoretically show that it is possible to increase the charge-pair separation probability by controlling the mobility anisotropy in heterojunction systems and in consequence to achieve higher efficiencies of organic photovoltaic devices.

• 전자공학회논문지D
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• 제35D권8호
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• pp.31-37
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• 1998

A new self-consistent hole mobility model that includes lattice and hole temeprature has been proposed. By including the lattice and hole temperatures as well as the effective transverse field and the interface fixed charge, the model predicted the saturation of hole drift velocity and showed the effects of coulomb scattering, surface phonon scattering, and surface roughness scattering. The calculated data by the model were compared with the reported experimental data and they were shown to agree quite well. The new model is expected to estimate the characteristics of very short channel devices in the in the hydrodynamic model simulation.