Photoluminescence Characterization of Carrier Recombination Centers in 4H-SiC Substrates by Utilizing below Gap Excitation

2017 ◽  
Vol 897 ◽  
pp. 315-318
Author(s):  
Keitaro Kondo ◽  
Norihiko Kamata ◽  
Hiroyuki Yaguchi ◽  
Shuhei Yagi ◽  
Takeshi Fukuda ◽  
...  
Keyword(s):  
Density Dependence ◽  
Intensity Change ◽  
Device Performance ◽  
Acceptor Pair ◽  
Carrier Recombination ◽  
Donor Acceptor ◽  
Recombination Centers ◽  
P Type ◽  
Growth Technology

Though the crystal growth technology of SiC is improving steadily, it is still crucial to reduce crystalline defects which act as carrier recombination (CR) centers and deteriorate device performance. We detected CR centers in a p-type 4H-SiC substrate by observing the intensity change of photoluminescence due to the addition of a below-gap excitation (BGE) light of 0.93[eV]. We noticed the temperature and the BGE density dependence of band edge (BE) emission in addition to donor acceptor pair (DAP) emission and discriminated the temperature effect from that of BGE. The BGE density dependence of the PL intensity quenching is different among the BE emission, B0- and C0-lines of the DAP, respectively. It gives us an important clue for understanding CR mechanisms inside the bandgap of SiC.

Photoluminescence Characterization of p-type GaN:Mg

1997 ◽  
Vol 482 ◽  
Author(s):  
Dorina Corlatan ◽  
Joachim Krüger ◽  
Christian Kisielowski ◽  
Ralf Klockenbrink ◽  
Yihwan Kim ◽  
...  
Keyword(s):  
Layer Structure ◽  
Growth Conditions ◽  
Buffer Layers ◽  
Near Band Edge ◽  
Acceptor Pair ◽  
Donor Acceptor ◽  
Si Doped ◽  
P Type ◽  
Mg Doped

AbstractWe report on results of low-temperature photoluminescence measurements performed on GaN films, grown by molecular beam epitaxy (MBE) on sapphire substrates. The GaN films are either Mg doped (p-type) or consist of a Mg-doped layer on top of a Si doped GaN layer (n-type). In the p-doped samples, the sharpness of the donor-acceptor-pair transition is striking, three phonon replicas are clearly resolved. A transition band occurs around 3.4 eV, which becomes dominant for samples with an np-layer structure. The position and the composition of the near band edge transitions are influenced by the growth of the buffer layers. Depending on the growth conditions a transition at 3.51 eV can be observed.

Photoluminescence characterization of Mg implanted GaN

1999 ◽  
Vol 595 ◽  
Author(s):  
C. Ronning ◽  
H. Hofsäss ◽  
A. Stötzler ◽  
M. Deicher ◽  
E.P. Carlson ◽  
...  
Keyword(s):  
Nitride Layer ◽  
Optically Active ◽  
Electrical Measurements ◽  
Acceptor Pair ◽  
Donor Acceptor ◽  
Optical Activation ◽  
Nitride Layers ◽  
P Type ◽  
High Degree

AbstractSingle crystalline (0001) gallium nitride layers, capped with a thin epitaxial aluminum nitride layer, were implanted with magnesium and subsequently annealed in vacuum to 1150-1300 oC for 10-60 minutes. Photoluminescence (PL) measurements showed the typical donor acceptor pair (DAP) transition at 3.25 eV after annealing at high temperatures, which is related to optically active Mg acceptors in GaN. After annealing at 1300 °C a high degree of optical activation of the implanted Mg atoms was reached in the case of low implantation doses. Electrical measurements, performed after removing the AlN-cap and the deposition of Pd/Au contacts, showed no p-type behavior of the GaN samples due to the compensation of the Mg acceptors with native n-type defects.

scholarly journals Photoluminescence characterization of Mg implanted GaN

2000 ◽  
Vol 5 (S1) ◽  
pp. 725-732 ◽  
Author(s):  
C. Ronning ◽  
H. Hofsäss ◽  
A. Stötzler ◽  
M. Deicher ◽  
E.P. Carlson ◽  
...  
Keyword(s):  
Nitride Layer ◽  
Optically Active ◽  
Electrical Measurements ◽  
Acceptor Pair ◽  
Donor Acceptor ◽  
Optical Activation ◽  
Nitride Layers ◽  
P Type ◽  
High Degree

Single crystalline (0001) gallium nitride layers, capped with a thin epitaxial aluminum nitride layer, were implanted with magnesium and subsequently annealed in vacuum to 1150-1300 °C for 10-60 minutes. Photoluminescence (PL) measurements showed the typical donor acceptor pair (DAP) transition at 3.25 eV after annealing at high temperatures, which is related to optically active Mg acceptors in GaN. After annealing at 1300 °C a high degree of optical activation of the implanted Mg atoms was reached in the case of low implantation doses. Electrical measurements, performed after removing the AlN-cap and the deposition of Pd/Au contacts, showed no p-type behavior of the GaN samples due to the compensation of the Mg acceptors with native n-type defects.

scholarly journals Photoluminescence Characterization of Nonradiative Recombination Centers in Light Emitting Materials by Utilizing Below-Gap Excitation: A Mini Review of Two-Wavelength Excited Photoluminescence

2015 ◽  
Vol 43 ◽  
pp. 1-9
Author(s):  
Norihiko Kamata ◽  
Abu Zafor Md. Touhidul Islam
Keyword(s):  
Quantum Wells ◽  
Electrical Contact ◽  
Intensity Change ◽  
Nonradiative Recombination ◽  
Excitation Light ◽  
Light Emitting ◽  
Recombination Centers ◽  
Pl Intensity ◽  
Trap Filling

We have developed an optical method of detecting and characterizing nonradiative recombination (NRR) centers without electrical contact. The method combines a below-gap excitation (BGE) light with a conventional above-gap excitation light in photoluminescence (PL) measurement, and discriminates the PL intensity change due to switching on and off the BGE. A quantitative analysis of the detected NRR centers became possible by utilizing the saturating tendency of the PL intensity change with increasing the BGE density due to trap filling effect. Some experimental results of AlGaAs, InGaN, and AlGaN quantum wells were shown to allocate the development and present status as well as to exemplify their interpretations.

Fluorescent P-Type 4H-SiC Grown by PVT Method

2016 ◽  
Vol 858 ◽  
pp. 326-330
Author(s):  
Shi Yi Zhuo ◽  
Xi Liu ◽  
Pao Gao ◽  
Wei Huang ◽  
Cheng Feng Yan ◽  
...  
Keyword(s):  
Visible Light ◽  
Room Temperature ◽  
Light Emission ◽  
Green Fluorescence ◽  
Acceptor Pair ◽  
Aluminum Doping ◽  
Visible Light Range ◽  
Donor And Acceptor ◽  
Donor Acceptor ◽  
P Type

Fluorescent SiC, which contains donor and acceptor impurities with optimum concentrations, can work as a phosphor for visible light emission by donor-acceptor-pair (DAP) recombination. In this work, 3 inch N-B-Al co-doped fluorescent 4H-SiC crystals are prepared by PVT method. The p-type fluorescent 4H-SiC with low aluminum doping concentration can show intensive yellow-green fluorescence at room temperature. N-B DAP peak wavelength shifts from 578nm to 525nm and weak N-Al DAP emission occurred 403/420 nm quenches, when the temperature increases from 4K to 298K. The aluminum doping induces higher defect concentration in the fluorescent crystal and decreases optical transmissivity of the crystal in the visible light range. It triggers more non-radiative recombination and light absorption losses in the crystal.

p-type conductivity and donor-acceptor pair emission in Cd1−xFexS dilute magnetic semiconductors

2006 ◽  
Vol 89 (26) ◽  
pp. 262118 ◽  
Author(s):  
X. J. Wu ◽  
D. Z. Shen ◽  
Z. Z. Zhang ◽  
J. Y. Zhang ◽  
K. W. Liu ◽  
...  
Keyword(s):  
Magnetic Semiconductors ◽  
Dilute Magnetic Semiconductors ◽  
Acceptor Pair ◽  
Type Conductivity ◽  
Donor Acceptor ◽  
Donor Acceptor Pair ◽  
P Type

scholarly journals On the origin of the 2.8 eV blue emission in p-type GaN:Mg : A time-resolved photoluminescence investigation

2001 ◽  
Vol 6 ◽  
Author(s):  
F. Shahedipour ◽  
B.W. Wessels
Keyword(s):  
Luminescence Intensity ◽  
Random Distribution ◽  
Blue Emission ◽  
Acceptor Pair ◽  
Time Resolved ◽  
Donor Acceptor ◽  
Shallow Acceptors ◽  
Donor Acceptor Pair ◽  
P Type ◽  
Time Resolved Photoluminescence

The decay dynamics of the 2.8 eV emission band in p-type GaN was investigated using time-resolved photoluminescence spectroscopy. The luminescence intensity decays non-exponentially. The decay dynamics were consistent with donor-acceptor pair recombination for a random distribution of pair distances. Calculations using the Thomas-Hopfield model indicated that recombination involves deep donors and shallow acceptors.

High quality p-type ZnO film grown on ZnO substrate by nitrogen and tellurium co-doping

2009 ◽  
Vol 1201 ◽  
Author(s):  
Seunghwan Park ◽  
Tsutomu Minegishi ◽  
jinsub Park ◽  
Hyunjae Lee ◽  
Toshinori Taishi ◽  
...  
Keyword(s):  
Electron Concentration ◽  
Hole Concentration ◽  
Nitrogen Concentration ◽  
Zno Film ◽  
Acceptor Pair ◽  
High Quality ◽  
Co Doping ◽  
Donor Acceptor ◽  
Doped Zno ◽  
P Type

AbstractNitrogen and tellurium co-doped ZnO (ZnO:[N+Te]) films have been grown on (0001) ZnO substrate by plasma-assisted molecular beam epitaxy. The electron concentration of tellurium doped ZnO (ZnO:Te) gradually increases, compared that of undoped ZnO (u-ZnO). On the other hand, conductivity of ZnO:[N+Te] changes from n-type to p-type characteristic with a hole concentration of 4×1016 cm-3. However, nitrogen doped ZnO film (ZnO:N) still remain as n-type conductivity with a electron concentration of 2.5×1017 cm-3. Secondary ion mass spectroscopy reveals that nitrogen concentration ([N]) of ZnO:[N+Te] film (2×1021 cm-3) is relatively higher than that of ZnO:N film (3×1020 cm-3). 10 K photoluminescence spectra shows that considerable improvement of emission properties of ZnO:[N+Te] with an emergence of narrow acceptor bound exciton (A°X, 3.359 eV) and donor-acceptor pair (DAP, 3.217 eV), compared with those of u-ZnO. Consequently, high quality p-type ZnO with high N concentration is realized by using Te and N co-doping technique due to reduction of Madelung energy.

scholarly journals Studies on Carbon as Alternative P-Type Dopant for Gallium Nitride

1999 ◽  
Vol 4 (S1) ◽  
pp. 526-531 ◽  
Author(s):  
U. Birkle ◽  
M. Fehrer ◽  
V. Kirchner ◽  
S. Einfeldt ◽  
D. Hommel ◽  
...  
Keyword(s):  
Thermal Activation ◽  
Atomic Layer ◽  
Typical Feature ◽  
Acceptor Pair ◽  
Carbon Doped ◽  
Order Of Magnitude ◽  
Donor Acceptor ◽  
Donor Acceptor Pair ◽  
P Type ◽  
Carbon Concentrations

GaN layers were grown by molecular beam epitaxy and doped with carbon of nominal concentrations ranging from 1016 cm−3 to 1020 cm−3. The incorporation of carbon leads to a reduction of the background electron concentration by one order of magnitude but the material remains n-type. For high carbon concentrations a re-increase of the carrier concentration is observed which is related to selfcompensation. Investigations of the donor-acceptor-pair luminescence show that doping with carbon is accompanied by the generation of a new donor exhibiting a thermal activation energy of about 55 meV. Layers grown by atomic layer epitaxy are marked by an increased intensity of the donor-acceptor-pair band luminescence which is attributed to the enforced incorporation of carbon onto the nitrogen sublattice. The yellow luminescence is found to be a typical feature of all carbon doped layers in contrast to nominally undoped samples.

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