Electrical and Optical Studies of Si-Implanted GaN

2001 ◽  
Vol 693 ◽  
Author(s):  
James A. Fellows ◽  
Yung Kee Yeo ◽  
Robert L. Hengehold ◽  
Leonid Krasnobaev
Keyword(s):  
Room Temperature ◽  
Electrical Activation ◽  
Electrical And Optical Properties ◽  
Implantation Temperature ◽  
Activation Efficiency ◽  
Hall Effect Measurements ◽  
Comparison Of The Results ◽  
Anneal Temperature ◽  
Activation Behavior ◽  
Different Doses

AbstractThe electrical and optical properties of Si-implanted GaN have been investigated as a function of ion dose, anneal temperature, and implantation temperature using Hall-effect measurements and photoluminescence. Implantation of 200 keV Si ions was made at room temperature and 800°C into MBE-grown GaN capped with 500 Å AlN at six different doses ranging from 1x1013 to 5x1015 cm-2. The samples were proximity cap annealed from 1050 to 1350°C for 5 min to 20 s using either a conventional furnace or rapid thermal annealing. For a given dose, electrical activation efficiencies and mobilities increase as the anneal temperature increases from 1050 to 1350°C. Generally, the higher the dose, the greater the activation efficiency for any given anneal temperature. For a sample implanted with a dose of 1x1015 cm-2 and annealed at 1350°C for 20 s, an electrical activation efficiency of 100% was obtained. Exceptional carrier concentrations and mobilities were obtained on all Si-implanted samples, and a comparison of the results was made between room temperature and 800°C implantation. Photoluminescence measurements were also performed in an effort to better understand the electrical activation behavior of the Si implants in GaN.

Optical Characterization of Mg- and Si-Implanted GaN

2001 ◽  
Vol 680 ◽  
Author(s):  
James A. Fellows ◽  
Yung Kee Yeo ◽  
Robert L. Hengehold ◽  
Leonid Krasnobaev
Keyword(s):  
Room Temperature ◽  
Deep Acceptor ◽  
Native Defects ◽  
Implantation Temperature ◽  
Luminescence Peak ◽  
Activation Efficiency ◽  
Deep Donor ◽  
Hall Effect Measurements ◽  
Anneal Temperature

ABSTRACTThe optical and electrical properties of Mg- and Si-implanted GaN were investigated using photoluminescence, cathodoluminescence, and Hall-effect measurements. Implantation of Mg, Si, Mg+Si, Mg+O, Mg+C, and Mg+P was made into undoped semi-insulating MBE-grown GaN at energies from 125 to 260 keV at room temperature and 800 oC with doses of 1x1014 to 5x1015 cm−2. The samples were capped with AlN and annealed at temperatures ranging from 1100 to 1300 oC for 9 s to 20 min. The dominant luminescence peak in all Mg-implanted and annealed GaN is a broad green luminescence (GL) band at 2.36 eV, which may be related to a deep donor-deep acceptor complex transition resulting from the Mg implant, residual implant damage, and/or native defects. The relative intensities of this GL band and secondary peaks from 2.75-3.28 eV vary as a function of implantation temperature, ion dose, species, and anneal temperature. All Mg single and dual implantation resulted in extremely resistive GaN layers, except Mg+Si, which resulted in weakly n-type GaN. However, the Si-implanted GaN produced an electrical activation efficiency as high as 73% after annealing at 1200 oC for 5 min.

The effects of substrate temperature on reactively evaporated a-Si:H

1990 ◽  
Vol 68 (3) ◽  
pp. 346-351 ◽  
Author(s):  
S. Zhang ◽  
R. G. Audas ◽  
D. E. Brodie
Keyword(s):  
Activation Energy ◽  
Substrate Temperature ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Dark Conductivity ◽  
Electrical Activation ◽  
Infrared Transmission ◽  
Electrical And Optical Properties ◽  
Main Technique ◽  
Transmission Measurements

The bonding configurations and the concentrations of hydrogen are important parameters that affect the electrical and optical properties as well as the Staebler–Wronsky effect. Infrared transmission measurements are used as the main technique to investigate the effect of substrate temperature Ts on the hydrogen content and bonding configurations in reactively evaporated a-Si:H. There is no measurable SiH peak in films made at low Ts. When Ts is increased to 450 K, the SiH peak is discernable, and the maximum SiH concentration is obtained for Ts = 540 K. SiH2 and(or) (SiH2)n concentrations are large at low Ts but decrease as Ts is increased. When samples made at low Ts are stored in air at room temperature, they take up oxygen and the SiH2 and(or) (SiH2)n concentration decreases with time after preparation. This phenomenon is not observed for samples made with Ts ≥ 540 K. The dark conductivity, optical band gap, and electrical activation energy are altered by varying the H concentration. When some samples [Formula: see text] are illuminated with AM1 radiation, a conductivity change of more than three orders of magnitude has been observed.

Electrical and Optical Properties of Si+ and P+ Implanted InP:Fe

1990 ◽  
Vol 201 ◽  
Author(s):  
Honglie Shen ◽  
Genqing Yang ◽  
Zuyao Zhou ◽  
Guanqun Xia ◽  
Shichang Zou
Keyword(s):  
Optical Properties ◽  
Silicon Nitride ◽  
Temperature Dependence ◽  
Optimal Condition ◽  
Room Temperature ◽  
Broad Band ◽  
Photoluminescence Spectra ◽  
Electrical And Optical Properties ◽  
Spectrum Measurement ◽  
Single Implant

AbstractDual implantations of Si+ and P+ into InP:Fe were performed both at 200°C and room temperature. Si+ ions were implanted by 150keV with doses ranging from 5×1013 /cm2 to 1×1015 /cm2, while P+ ions were implanted by 110keV. 160keV and 180keV with doses ranging from 1×l013 /cm2 to 1×1015 /cm2. Hall measurements and photoluminescence spectra were used to characterize the silicon nitride encapsulated annealed samples. It was found that enhanced activation can be obtained by Si+ and P+ dual implantations. The optimal condition for dual implantations is that the atomic distribution of implanted P overlaps that of implanted si with the same implant dose. For a dose of 5×l014 /cm2, the highest activation for dual implants is 70% while the activation for single implant is 40% after annealing at 750°C for 15 minutes. PL spectrum measurement was carried out at temperatures from 11K to 100K. A broad band at about 1.26eV was found in Si+ implanted samples, of which the intensity increased with increasing of the Si dose and decreased with increasing of the co-implant P+ dose. The temperature dependence of the broad band showed that it is a complex (Vp-Sip) related band. All these results indicate that silicon is an amphoteric species in InP.

ION CHANNELING AND PIXE STUDIES OF S IMPLANTATION IN GaAs

1992 ◽  
Vol 02 (02) ◽  
pp. 151-159
Author(s):  
LIU SHIJIE ◽  
WANG JIANG ◽  
HU ZAOHUEI ◽  
XIA ZHONGHUONG ◽  
GAO ZHIGIANG ◽  
...  
Keyword(s):  
Room Temperature ◽  
Dislocation Loops ◽  
Good Recovery ◽  
Electrical Measurements ◽  
X Ray ◽  
Defect Complexes ◽  
Ion Channeling ◽  
Transmission Electron ◽  
Activation Efficiency ◽  
Very High

GaAs (100) crystals were implanted with 100 keV S+ to a dose of 3×1015 cm−2 in a nonchanneling direction at room temperature, and treated with rapid thermal annealing (RTA). He+ Rutherford backscattering and particle-induced X-ray emission in channeling mode in combination with transmission electron microscopy (TEM) were used to study the damage and the lattice location of S atoms. It is revealed that the RTA at 950 °C for 10 sec has resulted in a very good recovery of crystallinity with a few residual defects in the form of dislocation loops, and a very high substitutionality (~90%). The activation efficiency and the Hall mobility of the implanted samples are found to be low after the electrical measurements. Based on these results an extended dopant diffusion effect for the residual defects and a correlation between the electrical properties and defect complexes are suggested.

About the Electrical Activation of 1×1020 cm-3 Ion Implanted Al in 4H-SiC at Annealing Temperatures in the Range 1500 - 1950°C

2018 ◽  
Vol 924 ◽  
pp. 333-338 ◽  
Author(s):  
Roberta Nipoti ◽  
Alberto Carnera ◽  
Giovanni Alfieri ◽  
Lukas Kranz
Keyword(s):  
Activation Energy ◽  
Sheet Resistance ◽  
Annealing Time ◽  
Thermal Activation ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Thermal Activation Energy ◽  
Electrical Activation ◽  
Temperature Range ◽  
Annealing Temperatures

The electrical activation of 1×1020cm-3implanted Al in 4H-SiC has been studied in the temperature range 1500 - 1950 °C by the analysis of the sheet resistance of the Al implanted layers, as measured at room temperature. The minimum annealing time for reaching stationary electrical at fixed annealing temperature has been found. The samples with stationary electrical activation have been used to estimate the thermal activation energy for the electrical activation of the implanted Al.

Electrical and Structural Properties of Al-Implanted and Annealed 4H-SiC

2007 ◽  
Vol 556-557 ◽  
pp. 343-346 ◽  
Author(s):  
M. Obernhofer ◽  
Michael Krieger ◽  
Frank Schmid ◽  
Heiko B. Weber ◽  
Gerhard Pensl ◽  
...  
Keyword(s):  
Hall Effect ◽  
Structural Properties ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Rutherford Backscattering ◽  
Electrical Activation ◽  
Implantation Damage ◽  
Aluminum Ions

Aluminum ions (Al+) were implanted at room temperature or at 500°C into n-type 4HSiC. The implantation damage (displaced Si atoms) and the electrical activation of Al+ ions (concentration of Al acceptors) were determined by Rutherford backscattering in channeling mode and Hall effect, respectively, as a function of the annealing temperature.

Structural, electrical, and optical property studies of indium-doped Hg0.8Cd0.2Te/Cd0.96Zn0.04Te heterostructures

1999 ◽  
Vol 14 (7) ◽  
pp. 2778-2782 ◽  
Author(s):  
M. S. Han ◽  
T. W. Kang ◽  
T. W. Kim
Keyword(s):  
Hall Effect ◽  
Ftir Spectra ◽  
Epitaxial Layers ◽  
High Quality ◽  
Electrical And Optical Properties ◽  
Vacancy Defects ◽  
Transmission Electron ◽  
Hall Effect Measurements ◽  
Transmission Measurements ◽  
Van Der Pauw

Transmission electron microsopy (TEM), Hall effect, and Fourier transform infrared (FTIR) transmission measurements were performed to investigate the structural, electrical, and optical properties of indium-doped Hg0.8Cd0.2Te epitaxial layers grown on Cd0.96Zn0.04Te (211) B substrates by molecular-beam epitaxy. The TEM measurements showed that high-quality Hg0.8Cd0.2Te epitaxial layers with interfacial abruptnesses were grown on the Cd0.96Zn0.04Te substrates. The Van der Pauw Hall effect measurements on typical indium-doped Hg0.8Cd0.2Te/Cd0.96Zn0.04Te heterostructures with a doping concentration of 6 × 1016 cm−3 at 10 K in a magnetic field of 0.5 T yielded a carrier density and a mobility of 2.2 × 1016 cm−3 and 40,000 cm2/V s, respectively. The FTIR spectra showed that the absorption edges of the indium-doped Hg0.8Cd0.2Te/Cd0.96Zn0.04Te heterostructures shifted to a shorter wavelength range than those of the undoped samples, which was caused by the Burstein–Moss effect. The FTIR spectra also showed that the transmittance intensities of the indium-doped Hg0.8Cd0.2Te/Cd0.96Zn0.04Te heterostructures increased compared with those of the undoped heterostructures, which is due to the compensation of the Hg vacancy defects by the indium atoms. These results indicate that the indium-doped Hg0.8Cd0.2Te epitaxial layers were high-quality n-type layers and that p-HgxCd1−xTe epilayers can be grown on indium-doped Hg0.8Cd0.2Te/Cd0.96Zn0.04Te heterostructures for the fabrication of HgxCd1−xTe photoconductors and photodiodes.

Electric and thermoelectric properties of CdTe/PbTe epitaxial nanocomposite

2014 ◽  
Vol 07 (06) ◽  
pp. 1440007
Author(s):  
Michal Szot ◽  
Krzysztof Dybko ◽  
Piotr Dziawa ◽  
Leszek Kowalczyk ◽  
Viktor Domukhovski ◽  
...  
Keyword(s):  
Thermoelectric Properties ◽  
Carrier Mobility ◽  
Room Temperature ◽  
Molecular Beam ◽  
High Quality ◽  
Polycrystalline Solid ◽  
Hall Effect Measurements ◽  
Shubnikov De Haas Oscillations

The electric and thermoelectric properties of novel, CdTe / PbTe layered nanocomposite material are investigated. The molecular beam epitaxy (MBE) method was used for preparation of samples with well controlled distances (from 20 to 70 nm) between the layers of CdTe nanograins embedded in PbTe thermoelectric matrix as well as with number of these layers from 2 to 10. The Hall effect measurements performed in temperature range from 4–300 K revealed that carrier mobility is strongly affected by scattering on CdTe grain boundaries. The observation of Shubnikov-de Haas oscillations confirms high quality of the samples and allows determination of effective mass of conducting electrons m* = 0.04m0. The measurements of the room temperature Seebeck coefficient together with electrical conductivity lead to the power factors which are comparable to those reported in PbTe / CdTe polycrystalline solid solutions.

An Electrical and Physical Study of Crystal Damage in High-Dose Al- and N-Implanted 4H-SiC

2017 ◽  
Vol 897 ◽  
pp. 411-414 ◽  
Author(s):  
Craig A. Fisher ◽  
Romain Esteve ◽  
Stefan Doering ◽  
Michael Roesner ◽  
Martin de Biasio ◽  
...  
Keyword(s):  
High Temperature ◽  
Room Temperature ◽  
High Dose ◽  
Stress Determination ◽  
Analysis Techniques ◽  
Physical Study ◽  
Crystal Damage ◽  
Activation Annealing ◽  
Anneal Temperature ◽  
High Dose Implantation

In this paper, an investigation into the crystal structure of Al-and N-implanted 4H-SiC is presented, encompassing a range of physical and electrical analysis techniques, with the aim of better understanding the material properties after high-dose implantation and activation annealing. Scanning spreading resistance microscopy showed that the use of high temperature implantation yields more uniform resistivity profiles in the implanted layer; this correlates with KOH defect decoration and TEM observations, which show that the crystal damage is much more severe in room temperature implanted samples, regardless of anneal temperature. Finally, stress determination by means of μRaman spectroscopy showed that the high temperature implantation results in lower tensile stress in the implanted layers with respect to the room temperature implantation samples.

Electrical and Optical Properties of Silicone Oil/Carbon Nanotube Nanocomposites

2021 ◽  
Vol 21 (4) ◽  
pp. 2185-2195
Author(s):  
Jeferson Matos Hrenechen ◽  
Celso de Araujo Duarte ◽  
Ney Pereira Mattoso Filho ◽  
Evaldo Ribeiro
Keyword(s):  
Optical Properties ◽  
Room Temperature ◽  
Conduction Mechanism ◽  
Silicone Oil ◽  
Optical Transmittance ◽  
Liquid Matrix ◽  
Electrical And Optical Properties ◽  
Multiwalled Carbon ◽  
Liquid Matrices ◽  
The Matrix

The present work describes the preparation and the investigation of the room temperature electrical and optical properties of a series of liquid nanocomposites (lnC) prepared with different concentrations of multiwalled carbon nanotubes (MWCNT) in a variety of liquid matrices: glycerin, Vaseline, glucose, propylene glycol and silicone oil (SIO). Special attention is deserved to the SIO matrix, owing to its convenient electrical properties for our purposes. We verified that a small percent fraction of MWCNT dispersed along the SIO matrix is capable of improving the electrical conductivity of the matrix by orders of magnitude, indicating that the MWCNT strongly participates in the electrical conduction mechanism. Also, the application of an external electric field to this lnC resulted in large changes in the optical transmittance, that were interpreted as a consequence of the fieldinduced MWCNT alignment into the liquid matrix. The characteristics of such a new category of nanocomposite in the liquid state suggest further studies.

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