Anneal mediated deep-level dynamics in GaInNAsSb dilute nitrides lattice-matched to GaAs

2019 ◽  
Vol 126 (14) ◽  
pp. 143104 ◽  
Author(s):  
Naoya Miyashita ◽  
Yilun He ◽  
Nazmul Ahsan ◽  
Yoshitaka Okada
Keyword(s):  
Deep Level ◽  
Dilute Nitrides ◽  
Lattice Matched

Deep Level Defect Studies in Mocvd-Grown InxGa1−sAs1−yNy Films Lattice-Matched to GaAs

1998 ◽  
Vol 535 ◽  
Author(s):  
Daewon Kwon ◽  
R. J. Kaplar ◽  
J. J. Boeckl ◽  
S. A. Ringel ◽  
A. A. Allerman ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Deep Level ◽  
Energy Levels ◽  
Resolution Limit ◽  
Defect States ◽  
Cross Sectional ◽  
Order Of Magnitude ◽  
Transient Spectroscopy ◽  
Lattice Matched ◽  
Dlts Spectra

AbstractDeep level defects in MOCVD-grown, unintentionally doped p-type InGaAsN films lattice matched to GaAs were investigated using deep level transient spectroscopy (DLTS) measurements. As-grown p-InGaAsN showed broad DLTS spectra suggesting that there exists a broad distribution of defect states within the band-gap. Moreover, the trap densities exceeded 1015 cm−3. Cross sectional transmission electron microscopy (TEM) measurements showed no evidence for threading dislocations within the TEM resolution limit of 107 cm−2. A set of samples was annealed after growth for 1800 seconds at 650 °C to investigate the thermal stability of the traps. The DLTS spectra of the annealed samples simplified considerably, revealing three distinct hole trap levels with energy levels of 0.10 eV, 0.23 eV, and 0.48 eV above the valence band edge with trap concentrations of 3.5 × 1014 cm−3, 3.8 × 1014 cm−3, and 8.2 × 1014 cm−3, respectively. Comparison of as-grown and annealed DLTS spectra showed that post-growth annealing effectively reduced the total trap concentration by an order of magnitude across the bandgap. However, the concentration of a trap with an energy level of 0.48 eV was not affected by annealing indicating a higher thermal stability for this trap as compared with the overall distribution of shallow and deep traps.

Ge Related Deep Level Luminescence in InGaAs Lattice Matched to InP

1989 ◽  
Vol 163 ◽  
Author(s):  
S.S. Chandvankar ◽  
A.K. Srivastava ◽  
B.M. Arora ◽  
D.K. Sharma
Keyword(s):  
Low Temperature ◽  
Carrier Concentration ◽  
Lower Energy ◽  
Deep Level ◽  
Peak Position ◽  
Type Conductivity ◽  
Pl Spectra ◽  
P Type ◽  
Lattice Matched ◽  
Ge Doping

AbstractPhotoluminescence and Hall measurements are reported on Ge doped InGaAs layers lattice matched to InP. Ge doping of these samples results in highly compensated material, with the highest Ge content sample giving a p type conductivity with carrier concentration of 5 ×1017 cm-3. Low temperature PL spectra of these samples show a broad peak from 0.55 to 0.77 eV due to Ge. The peak of luminescence shifts to lower energy with increasing Ge content. The peak position shifts to higher energy with increasing excitation like in a D-A pair transition. The PL spectra have been explained on the basis of a model which assumes tail states near the band edges due to disorder produced by the presence of Ge in the lattice.

Theoretical Investigation of Strain-balanced GaP1−xNx/GaAs1−yNy superlattices lattice-matched to Si(001) for 1.5-1.8 eV photonic applications

2006 ◽  
Vol 934 ◽  
Author(s):  
Lekhnath Bhusal ◽  
Wenkai Zhu ◽  
Alex Freundlich
Keyword(s):  
Electronic Band Structure ◽  
Band Alignment ◽  
Thin Layers ◽  
Photon Absorption ◽  
Strain Effect ◽  
Type I ◽  
Dilute Nitrides ◽  
Electronic Band ◽  
Short Period ◽  
Lattice Matched

ABSTRACTDilute nitrides alloys of GaP1−x−yAsyNx alloys have attracted much attention since they exhibit a direct bandgap and their lattice constant matches the one of silicon for y=4.7x-0.1. Thus these alloys offer interesting perspectives for the monolithic integration of III-V optoelectronics with the silicon technology. For practically achievable nitrogen composition (x ≤ 0.04), the band gap of GaP1−x−yAsyNx alloys lattice matched to Si is limited to about 1.75 eV. One may attempt to expand the operation wavelength of these dilute nitrides by fabricating a short period strain-balanced GaP1−xNx/GaAs1−yNy superlattices on silicon where ultra-thin layers of GaAs1−yNy (compressively strained) and GaP1−xNx (tensilely strained) are alternated and where the thickness of each layer is maintained to below the onset of the lattice relaxation.In this work we present a theoretical study of the electronic band structure of these strain-balanced (and lattice matched to Si) superlattices in the vicinity of the center of the Brillouin zone (Γ-point). A six-band Kane Hamiltonian modified to account for the strain effect and the band anti-crossing model are used to describe the electronic states of the highly strained zinc blende GaP1−xNx and GaAs1−yNy ternaries. The evolution of the conduction band minima and valence subbands maxima of GaP1−xNx and GaAs1−yNy indicates the occurrence of a type I band alignment for the superlattices involving the mj = ±3/2, ±1/2 valence subbands in the range of compositions of interest.A transfer matrix method has been used to determine the electron and hole minibands of the superlattice structure, predicting the evolution of the band edge transition energies for different nitrogen compositions and alloying/thickness combinations. The results of calculations show the potential to obtain room-temperature photon absorption/emission energies as low as 1.57 eV for a typical nitrogen composition of 5%. The proposed strain balanced structure, thus offers the potential for bandgap engineering ranging from the near IR to visible with host of major applications in silicon-based optoelectronics and multi-bandgap photovoltaics.

Defects in Mg-Doped InP and GaInAs Grown by Omvpe

1986 ◽  
Vol 90 ◽  
Author(s):  
Fred R. Bacher ◽  
H. Cholan ◽  
Wallace B. Leigh
Keyword(s):  
Lattice Mismatch ◽  
Deep Level ◽  
Shallow Donor ◽  
Band Edge Emission ◽  
Pressure System ◽  
Group Iii ◽  
Heavily Doped ◽  
Transient Spectroscopy ◽  
P Type ◽  
Lattice Matched

ABSTRACTWe report on the defects present in doped InP and GaInAs grown by organometallic vapor phase epitaxy (OMVPE). The material was grown in an atmospheric pressure system using group III trimethyl sources, arsine and phosphine. Bis(cyclopentadienyl) magnesium (Cp2Mg) was present as a p-type source of magnesium. Defects in as-grown material were characterized using photoluminescence (PL), Hall-effect, and deep level transient spectroscopy (DLTS). Various levels of Mg doping were investigated, ranging from 5 × 1015 to 1 × 1019 cm−3. Radiative defects were observed at 77 K corresponding to PL emission from conduction band/shallow donor to acceptor levels including emission at 1.37 eV identified as the shallow hydrogenic acceptor, and emission lines at 1.3 eV and 1.0 eV in heavily doped material. Corresponding hole traps in InP:Mg were observed by DLTS having thermal activation energies of 0.20 and 0.40 eV, the 0.40 eV trap being the dominant defect in p-type InP. In GaInAs grown near lattice-matched to InP, radiative emission is also observed from deep centers 100 meV from band edge emission. This emission is observed to be related to lattice-mismatch of the ternary with the InP, and is found to be accentuated and broadened in GaInAs doped with Mg.

Using Dilute Nitrides to Achieve Record Solar Cell Efficiencies

2013 ◽  
Vol 1538 ◽  
pp. 161-166 ◽  
Author(s):  
Rebecca Jones-Albertus ◽  
Emily Becker ◽  
Robert Bergner ◽  
Taner Bilir ◽  
Daniel Derkacs ◽  
...  
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
New World ◽  
Device Performance ◽  
Dilute Nitride ◽  
Dilute Nitrides ◽  
High Quality ◽  
Multijunction Solar Cells ◽  
World Records ◽  
Lattice Matched

ABSTRACTHigh quality dilute nitride subcells for multijunction solar cells are achieved using GaInNAsSb. The effects on device performance of Sb composition, strain and purity of the GaInNAsSb material are discussed. New world records in efficiency have been set with lattice-matched InGaP/GaAs/GaInNAsSb triple junction solar cells and a roadmap to 50% efficiency with lattice-matched multijunction solar cells using GaInNAsSb is shown.

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