III-V族可见光半导体材料生长及其性质研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

III-V族和碳杂质对硅中热施主的影响

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

III-V族半导体的喇曼散射研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

六角III-V氮化物量子阱的电子结构和光学性质

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

III-V族半导体低维结构材料的平面光学各向异性

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

III－V族氮化物的生长及其光学性质

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

III-V族半导体低维结构与新型合金材料的光学性质

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

III-V-N 半导体材料光学性质的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

III-V族低维半导体材料偏振相关的光学性质

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Revised ab initio natural band offsets of all group IV, II-VI, and III-V semiconductors

Using an all-electron band structure approach, we have systematically calculated the natural band offsets between all group IV, III-V, and II-VI semiconductor compounds, taking into account the deformation potential of the core states. This revised approach removes assumptions regarding the reference level volume deformation and offers a more reliable prediction of the "natural" unstrained offsets. Comparison is made to experimental work, where a noticeable improvement is found compared to previous methodologies.

Temperature dependent spectral response characteristic of III-V compound tandem cell

The GaInP/GaAs/Ge triple-junction tandem cells with a conversion efficiency of 27.1% were fabricated using metalorganic chemical vapor deposition (MOCVD) technique. Temperature dependence of the spectral response measurements of the GaInP/GaAs/Ge tandem cell was performed by a quantum efficiency system at temperatures ranging from 25A degrees C to 160A degrees C. The red-shift phenomena of the absorption limit for all subcells were observed with increasing temperature, which is dued to the energy gap narrowing with temperature. The short-circuit current densities (J (sc)) of GaInP, GaAs and Ge subcells at room temperature calculated based on the spectral response data were 12.9, 13.7 and 17 mA/cm(2), respectively. The temperature coefficient of J (sc) for the tandem cell was determined to be 8.9 mu A/(cm(2) center dot A degrees C), and the corresponding temperature coefficient of the open-circuit voltage deduced from the series-connected model was -6.27 mV/A degrees C.

Controlled growth of III-V compound semiconductor nano-structures and their application in quantum-devices

This paper reviews our work on controlled growth of self-assembled semiconductor nanostructures, and their application in light-emission devices. High-power, long-life quantum dots (QD) lasers emitting at similar to 1 mu m, red-emitting QD lasers, and long-wavelength QD lasers on GaAs substrates have successfully been achieved by optimizing the growth conditions of QDs.

Impact of polarization on quasi-two-dimensional exciton and barrier-width dependence of the exciton associated transition in wurtzite III-V nitride quantum wells

Excitonic states in AlxGa1-xN/GaN quantum wells (QWs) are studied within the framework of effective-mass theory. Spontaneous and piezoelectric polarizations are included and their impact on the excitonic states and optical properties are studied. We witnessed a significant blue shift in transition energy when the barrier width decreases and we attributed this to the redistribution of the built-in electric field between well layers and barrier layers. For the exciton the binding energies, we found in narrow QWs that there exists a critical value for barrier width, which demarcates the borderline for quantum confinement effect and the quantum confined Stark effect. Exciton and free carrier radiative lifetimes are estimated by simple argumentation. The calculated results suggest that there are efficient non-radiative mechanisms in narrow barrier QWs. (C) 2002 Elsevier Science Ltd. All rights reserved.

Effects of piezoelectricity and spontaneous polarization on electronic and optical properties of wurtzite III-V nitride quantum wells

A theoretical model accounting for the macropolarization effects in wurtzite III-V nitrides quantum wells (QWs) is presented. Energy dispersions and exciton binding energies are calculated within the framework of effective-mass theory and variational approach, respectively. Exciton-associated transitions (EATs) are studied in detail. An energy redshift as high as 450 meV is obtained in Al0.25GaN0.75/GaN QWs. Also, the abrupt reduction of optical momentum matrix elements is derived as a consequence of quantum-confined Stark effects. EAT energies are compared with recent photoluminescence (PL) experiments and numerical coherence is achieved. We propose that it is the EAT energy, instead of the conduction-valence-interband transition energy that is comparable with the PL energy. To restore the reduced transition rate, we apply an external electric field. Theoretical calculations show that with the presence of the external electric field the optical matrix elements for EAT increase 20 times. (C) 2001 American Institute of Physics.

Point defects in III-V compound semiconductors

Point defects in III-V compound semiconductors were analyzed systematically in this paper. The effects of substitutes, antisites, interstitials, and vacancies on lattice parameters in III-V compound semiconductors were calculated with a simple model. The formation energies of vacancies in compound semiconductors can be obtained by this calculation. A practical technique established on this model has been utilized for measuring the stoichiometry in GaAs. The relationship between stoichiometry and deep level centers in GaAs was also investigated.