Doping Studies of n- and p-Type AlxGa1-xN Grown by ECR-Assisted MBE

1996 ◽  
Vol 449 ◽  
Author(s):  
D. Korakakis ◽  
H. M. Ng ◽  
K. F. Ludwig ◽  
T. D. Moustakas
Keyword(s):  
Carrier Concentration ◽  
Alloy Scattering ◽  
Al Content ◽  
Ecr Plasma ◽  
Hall Effect Measurements ◽  
Si Doped ◽  
Long Range Ordering ◽  
Power Measurements ◽  
P Type ◽  
Mg Doped

ABSTRACTAlxGal−xN films (x≤0.60) were grown on c-plane sapphire and (0001) 6H-SiC substrates using ECR plasma assisted Molecular Beam Epitaxy. Evidence of long range ordering in the investigated AlxGal−xN films is presented. Without intentional dopants the films are semi-insulating with resistivities ranging from 103 to 105 Ω.cm. The films were doped n-type with Si and p-type with Mg. The carrier concentration in the Si doped films, as determined by Hall effect measurements, was between 1016 to 1019 cm−3. At constant Si cell temperature, the carrier concentration was found to be reduced with AlN mole fraction, consistent with the observation that the donor ionization energy increases with Al content. Correspondingly, the electron mobility decreases with Al concentration, a result attributed to alloy scattering. The Mg doped films were found to exhibit p-type conductivity by thermoelectric power measurements with resistivities varying from 3 to 30 Ω-cm.

Effect of Cu doping on the electrical Properties of ZnTe by Vacuum Thermal Evaporation

2018 ◽  
Vol 31 (3) ◽  
pp. 20
Author(s):  
Sarmad M. M. Ali ◽  
Alia A.A. Shehab ◽  
Samir A. Maki
Keyword(s):  
Activation Energy ◽  
Electrical Conductivity ◽  
Hall Effect ◽  
Carrier Concentration ◽  
Hall Mobility ◽  
Cu Doping ◽  
Before And After ◽  
Hall Effect Measurements ◽  
Evaporation Technique ◽  
P Type

In this study, the ZnTe thin films were deposited on a glass substrate at a thickness of 400nm using vacuum evaporation technique (2×10-5mbar) at RT. Electrical conductivity and Hall effect measurements have been investigated as a function of variation of the doping ratios (3,5,7%) of the Cu element on the thin ZnTe films. The temperature range of (25-200°C) is to record the electrical conductivity values. The results of the films have two types of transport mechanisms of free carriers with two values of activation energy (Ea1, Ea2), expect 3% Cu. The activation energy (Ea1) increased from 29meV to 157meV before and after doping (Cu at 5%) respectively. The results of Hall effect measurements of ZnTe , ZnTe:Cu films show that all films were (p-type), the carrier concentration (1.1×1020 m-3) , Hall mobility (0.464m2/V.s) for pure ZnTe film, increases the carrier concentration (6.3×1021m-3) Hall mobility (2m2/V.s) for doping (Cu at 3%) film, but  decreases by increasing Cu concentration.

scholarly journals Electrical Properties of Cubic InN And GaN Epitaxial Layers as a Function of Temperature

2000 ◽  
Vol 5 (S1) ◽  
pp. 216-222
Author(s):  
J.R.L. Fernandez ◽  
V.A. Chitta ◽  
E. Abramof ◽  
A. Ferreira da Silva ◽  
J.R. Leite ◽  
...  
Keyword(s):  
Activation Energy ◽  
Electrical Properties ◽  
Carrier Concentration ◽  
Doping Level ◽  
Type Conductivity ◽  
Si Doping ◽  
Donor And Acceptor ◽  
Cubic Gan ◽  
Si Doped ◽  
P Type

Carrier concentration and mobility were measured for intrinsic cubic InN and GaN, and for Si-doped cubic GaN as a function of temperature. Metallic n-type conductivity was found for the InN, while background p-type conductivity was observed for the intrinsic GaN layer. Doping the cubic GaN with Si two regimes were observed. For low Si-doping concentrations, the samples remain p-type. Increasing the Si-doping level, the background acceptors are compensated and the samples became highly degenerated n-type. From the carrier concentration dependence on temperature, the activation energy of the donor and acceptor levels was determined. Attempts were made to determine the scattering mechanisms responsible for the behavior of the mobility as a function of temperature.

scholarly journals Optical and Transport Properties of p-Type GaAs

2012 ◽  
Vol 36 (1) ◽  
pp. 97-107 ◽  
Author(s):  
Mehnaz Sharmin ◽  
Shamima Choudhury ◽  
Nasrin Akhtar ◽  
Tahmina Begum
Keyword(s):  
Light Intensity ◽  
Carrier Concentration ◽  
Hall Coefficient ◽  
Hall Mobility ◽  
Room Temperature ◽  
Diffraction Method ◽  
Lattice Parameter ◽  
Band Gap Energy ◽  
Hall Effect Measurements ◽  
P Type

Electrical properties such as electrical resistivity, Hall coefficient, Hall mobility, carrier concentration of p-type GaAs samples were studied at room temperature (300 K). Resistivity was  found to be of the order of 5.6 × 10-3?-cm. The Hall coefficient (RH) was calculated to be 7.69 × 10-1cm3/C and Hall mobility (?H) was found to be 131cm2/V-s at room temperature from Hall effect   measurements. Carrier concentration was estimated to be 8.12 × 1018/cm3 and the Fermi level was calculated directly from carrier density data which was 0.33 eV. Photoconductivity measurements  were carried on by varying sample current, light intensity and temperature at constant chopping     frequency 45.60 Hz in all the cases mentioned above. It was observed that within the range of sample current 0.1 - 0.25mA photoconductivity remains almost constant at room temperature 300K and it was found to be varying non-linearly with light intensity within the range 37 - 12780 lux. Photoconductivity was observed to be increasing linearly with temperature between 308 and 428 K. Absorption coefficient (?) of the samples has been studied with variation of wavelength (300 -  2500 nm). The value of optical band gap energy was calculated between 1.34 and 1.41eV for the material from the graph of (?h?)2 plotted against photon energy. The value of lattice parameter (a) was found to be 5.651 by implying X-ray diffraction method (XRD).DOI: http://dx.doi.org/10.3329/jbas.v36i1.10926Journal of Bangladesh Academy of Sciences, Vol. 36, No. 1, 97-107, 2012 

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.

AlGaN/GaN/AlGaN double-heterojunction blue LEDs on 6H-SiC substrates

1995 ◽  
Vol 395 ◽  
Author(s):  
Hua-Shuang Kong ◽  
Michelle Leonard ◽  
Gary Bulman ◽  
Gerry Negley ◽  
John Edmond
Keyword(s):  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Blue Color ◽  
Deep Blue ◽  
Double Heterojunction ◽  
Si Doped ◽  
P Type ◽  
Peak Emission ◽  
Mg Doped

ABSTRACTBlue LEDs with double-heterojunction (DH) have been produced in AIN-GaN system grown on n-type 6H-SiC substrates via metalorganic chemical vapor deposition (MOCVD). These devices employ a GaN active layer bordered by Mg doped p-type Al0.1Ga0.9N and Si doped n-type Al0.1Ga0.9N. A vertical device design was utilized with a p-type Au contact centered on the chip top side for wire bonding. The backside contact to the SiC is Ni. The peak emission from these devices is 430 nm with a FWHM of 65 nm, producing a deep blue color. The output power is 1.7 mW at 20 mA which corresponds to an external quantum efficiency of 3%.

High p-type conduction in high-Al content Mg-doped AlGaN

2013 ◽  
Vol 102 (1) ◽  
pp. 012105 ◽  
Author(s):  
Toru Kinoshita ◽  
Toshiyuki Obata ◽  
Hiroyuki Yanagi ◽  
Shin-ichiro Inoue
Keyword(s):  
Al Content ◽  
P Type ◽  
High Al Content ◽  
Type Conduction ◽  
Mg Doped

Hydrogenation of Gallium Nitride

1993 ◽  
Vol 325 ◽  
Author(s):  
M. S. Brandt ◽  
N. M. Johnson ◽  
R. J. Molnar ◽  
R. Singh ◽  
T. D. Moustakas
Keyword(s):  
Comparative Study ◽  
Conduction Band ◽  
Room Temperature ◽  
Hole Concentration ◽  
Conduction Band Edge ◽  
Order Of Magnitude ◽  
Si Doped ◽  
Donor State ◽  
P Type ◽  
Mg Doped

AbstractA comparative study of the effects of hydrogen in n-type (unintentionally and Si-doped) as well as p-type (Mg-doped) MBE-grown GaN is presented. Hydrogenation above 500°C reduces the hole concentration at room temperature in the p-type material by one order of magnitude. Three different microscopic effects of hydrogen are suggested: Passivation of deep defects and of Mg-acceptors due to formation of hydrogen-related complexes and the introduction of a hydrogenrelated donor state 100 meV below the conduction band edge.

P- and N-Type Doping of Mbe Grown Cubic GaN/GaAs Epilayers

1998 ◽  
Vol 537 ◽  
Author(s):  
D.J. As ◽  
T. Simonsmeier ◽  
J. Busch ◽  
B. Schöttker ◽  
M. Lübbers ◽  
...  
Keyword(s):  
Low Temperature ◽  
Shallow Donor ◽  
Pressure Curve ◽  
Blue Band ◽  
Vapor Pressure Curve ◽  
Cubic Gan ◽  
Donor Acceptor ◽  
Hall Effect Measurements ◽  
Si Doped ◽  
P Type

AbstractP-type doping with Mg and n-type doping with Si of cubic GaN (c-GaN) epilayers is reported. Cubic GaN films are grown by if-plasma assisted MBE on semi-insulating GaAs (001) substrates at a substrate temperature of 720°C. Elemental Mg and Si are evaporated from thermal effusions cells. Secondary ion mass spectroscopy (SIMS), low temperature photoluminescence (PL) and temperature dependent Hall-effect measurements are used to study the incorporation, optical and electrical properties. A Mg related shallow donor-acceptor transiton at 3.04 eV with an acceptor activation energy of EA= 0.230 eV is observed by low temperature PL. At Mg concentrations above 1018 cm-3 the dominance of a broad blue band indicates that also in c-GaN Mg is incorporated at different lattice sites or forms complexes. Si-doped c-GaN epilayers are n-type with electron concentrations up to 5*1019 cm-3. The incorporation of Si follows exactly the vapor pressure curve of Si, indicating a sticking coefficient of I for Si in c-GaN. With increasing Si-concentration the intensity of the near-band luminescence continuously increases and broadens.

Mbe-Growth of InAs and GaSb Epitaxial Layers on GaAs Substrates

1989 ◽  
Vol 145 ◽  
Author(s):  
J. R. Söderström ◽  
D.H. Chow ◽  
T.C. McGill ◽  
T.J. Watson
Keyword(s):  
Hall Effect ◽  
Carrier Concentration ◽  
Growth Parameters ◽  
Hole Mobility ◽  
Extensive Study ◽  
Semiconductor Films ◽  
Mbe Growth ◽  
Gaas Substrates ◽  
Hall Effect Measurements ◽  
P Type

AbstractWe have grown a number of InAs and GaSb bulk layers on GaAs substrates and studied the properties of the semiconductor films as a function of the various growth parameters. Preliminary results from GaSb growth are presented in addition to an extensive study of InAs growth. The films were characterized during growth by RHEED. RHEED-oscillations were observed during both InAs and GaSb growths. Hall effect measurements yielded peak electron mobilities for InAs of 18,900 cm2/Vs at 300 K and 35,000 cm2/Vs at 77 K. For GaSb the as grown layers were found to be p-type with a carrier concentration of 9x1015cm-3 and a hole mobility of 910 cm2 /Vs at 300 K.

scholarly journals Improvement of p-Type AlGaN Conductivity with an Alternating Mg-Doped/Un-Doped AlGaN Layer Structure

Micromachines ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 835
Author(s):  
Chi-Chung Chen ◽  
Yu-Ren Lin ◽  
Yu-Wei Lin ◽  
Yu-Cheng Su ◽  
Chung-Chi Chen ◽  
...  
Keyword(s):  
Sheet Resistance ◽  
Layer Structure ◽  
Reference Sample ◽  
Impurity Scattering ◽  
Hole Mobility ◽  
Al Content ◽  
Ionized Impurity Scattering ◽  
Layer Structures ◽  
P Type ◽  
Mg Doped

Using molecular beam epitaxy, we prepared seven p-type AlGaN samples of ~25% in Al content, including six samples with Mg-doped/un-doped AlGaN alternating-layer structures of different layer-thickness combinations, for comparing their p-type performances. Lower sheet resistance and higher effective hole mobility are obtained in a layer-structured sample, when compared with the reference sample of uniform Mg doping. The improved p-type performance in a layer-structured sample is attributed to the diffusion of holes generated in an Mg-doped layer into the neighboring un-doped layers, in which hole mobility is significantly higher because of weak ionized impurity scattering. Among the layer-structured samples, that of 6/4 nm in Mg-doped/un-doped thickness results in the lowest sheet resistance (the highest effective hole mobility), which is 4.83 times lower (4.57 times higher) when compared with the sample of uniform doping. The effects of the Mg-doped/un-doped layer structure on p-type performance in AlGaN and GaN are compared.

Sign in / Sign up

Export Citation Format

Share Document