P-type GaN epitaxial layers and AlGaN/GaN heterostructures with high hole concentration and mobility grown by HVPE

ABSTRACTIn this paper we report p-GaN growth by hydride vapor phase epitaxy (HVPE) on sapphire substrates. Mg or Zn impurities were used for doping. Layer thickness ranged from 2 to 5 microns. For both impurities, as-grown GaN layers had p-type conductivity. Concentration NA-ND was varied from 1016 to 1018 cm−3. An annealing procedure at 750°C in argon ambient typically increased the concentration NA-ND in 1.5–3.5 times. For Mg doped GaN layers, room temperature hole mobility of 80 cm2V−1s−1 was measured by conventional Van Der Pau Hall effect technique for material having hole concentration of about 1x1018 cm−3. Initial results on highly electrically conducting p-type AlGaN/GaN heterostructures doped with Zn are also reported.

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Electrical Characterization of MOVPE-Grown P-Type GaN:Mg Against Annealing Temperature

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300003227 ◽

1999 ◽

Vol 4 (S1) ◽

pp. 665-670 ◽

Cited By ~ 1

Author(s):

Shizuo Fujita ◽

Mitsuru Funato ◽

Doo-Cheol Park ◽

Yoshifumi Ikenaga ◽

Shigeo Fujita

Keyword(s):

Annealing Temperature ◽

Hole Concentration ◽

Electrical Characterization ◽

Sapphire Substrates ◽

Electrical Degradation ◽

Scattering Centers ◽

Hall Effect Measurements ◽

P Type ◽

Mg Doped

Hall effect measurements have been applied for the electrical characterization of p-type Mg-doped GaN grown by metalorganic vapor-phase epitaxy on sapphire substrates in terms of annealing temperature for dehydrogenation (N2 annealing) and hydrogenation (H2 annealing) of the acceptors. With the N2 annealing temperature from 600 to 900 °C for dehydrogenation, both hole concentration and mobility increases, showing more activation of acceptors and less incorporation of unfavorable scattering centers probably originating from Mg-H bondings. The N2 annealing at higher than the growth temperature results in reduced hole concentration, but the mobility gets higher. Some defects compensating acceptors may be induced at high temperature annealing, but they seem to be no scattering centers and be inactivated by successive hydrogenation and re-dehydrogenation at the optimum dehydrogenation temperature 900 °C. The electrical degradation of GaN due to thermal damage is not very destructive and can be well recovered by annealing treatments.

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Electrical Characterization of MOVPE-GROWN P-Type GaN:Mg Against Annealing Temperature

MRS Proceedings ◽

10.1557/proc-537-g6.31 ◽

1998 ◽

Vol 537 ◽

Cited By ~ 2

Author(s):

Shizuo Fujita ◽

Mitsuru Funato ◽

Doo-Cheol Park ◽

Yoshifumi Ikenaga ◽

Shigeo Fujita

Keyword(s):

Annealing Temperature ◽

Hole Concentration ◽

Electrical Characterization ◽

Sapphire Substrates ◽

Electrical Degradation ◽

Scattering Centers ◽

Hall Effect Measurements ◽

P Type ◽

Mg Doped

AbstractHall effect measurements have been applied for the electrical characterization of p-type Mg-doped GaN grown by metalorganic vapor-phase epitaxy on sapphire substrates in terms of annealing temperature for dehydrogenation (N2 annealing) and hydrogenation (H2 annealing) of the acceptors. With the N2 annealing temperature from 600 to 900°C for dehydrogenation, both hole concentration and mobility increases, showing more activation of acceptors and less incorporation of unfavorable scattering centers probably originating from Mg-H bondings. The N2 annealing at higher than the growth temperature results in reduced hole concentration, but the mobility gets higher. Some defects compensating acceptors may be induced at high temperature annealing, but they seem to be no scattering centers and be inactivated by successive hydrogenation and re-dehydrogenation at the optimum dehydrogenation temperature 900°C. The electrical degradation of GaN due to thermal damage is not very destructive and can be well recovered by annealing treatments.

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MOCVD Growth of High-Hole Concentration (>2×1019 cm−3) P-Type InGaN for Solar Cell Application

MRS Proceedings ◽

10.1557/proc-1123-1123-p07-02 ◽

2008 ◽

Vol 1123 ◽

Cited By ~ 1

Author(s):

Hongbo Yu ◽

Andrew Melton ◽

Omkar Jani ◽

Balakrishnam Jampana ◽

Shenjie Wang ◽

...

Keyword(s):

Solar Cell ◽

Hole Concentration ◽

Molar Ratio ◽

Activation Temperature ◽

Solar Cell Application ◽

Mocvd Growth ◽

High Hole Concentration ◽

P Type ◽

Photovoltaic Material ◽

Mg Doped

AbstractInGaN alloys are widely researched in diverse optoelectronic applications. This material has also been demonstrated as a photovoltaic material. This paper presents the study to achieve optimum electrically active p-type InGaN epi-layers. Mg doped InGaN films with 20% In composition are grown on GaN templates/sapphire substrates by MOCVD. It is found that the hole concentration of p-type InGaN depends strongly on the Mg flow rate and V/III molar ratio and hole concentration greater than 2×1019 cm−3 has been achieved at room temperature. The optimum activation temperature of Mg-doped InGaN layer has been found to be 550-600°C, which is lower than that of Mg-doped GaN. A solar cell was realized successfully using the InGaN epi-layers presented here.

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Highly p-Type a-GaN Grown on r-Plane Sapphire Substrate

MRS Proceedings ◽

10.1557/proc-0892-ff17-06 ◽

2005 ◽

Vol 892 ◽

Author(s):

Yosuke Tsuchiya ◽

Yoshizane Okadome ◽

Hiroko Furukawa ◽

Akira Honshio ◽

Yasuto Miyake ◽

...

Keyword(s):

Gas Flow ◽

Hole Concentration ◽

Hole Mobility ◽

Hall Effect Measurement ◽

Type A ◽

Temperature Dependent ◽

Type C ◽

Activation Ratio ◽

P Type ◽

Mg Doped

AbstractMg-doped p-type a-plane GaN films were grown on unintentionally doped a-plane GaN templates by metalorganic vapor phase epitaxy (MOVPE). The Mg concentration in a-plane GaN increased with increasing Mg source gas flow rate. A maximum hole concentration of 2.0 × 1018 cm-3 with a hole mobility of 4.5 cm2/Vs and resistivity of 0.7 Ω·cm were achieved. The activation ratio was 5.0 × 10-2. It was found that a maximum hole concentration in p-type a-plane GaN was higher than that in p-type c-plane GaN. The activation energy of Mg acceptors in p-type a-plane GaN with the maximum hole concentration was found to be 118 meV by temperature-dependent Hall-effect measurement.

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High hole concentration of p-type InGaN epitaxial layers grown by MOCVD

Thin Solid Films ◽

10.1016/j.tsf.2005.07.084 ◽

2006 ◽

Vol 498 (1-2) ◽

pp. 113-117 ◽

Cited By ~ 15

Author(s):

Po-Chang Chen ◽

Chin-Hsiang Chen ◽

Shoou-Jinn Chang ◽

Yan-Kuin Su ◽

Ping-Chuan Chang ◽

...

Keyword(s):

Hole Concentration ◽

Epitaxial Layers ◽

High Hole Concentration ◽

P Type

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Regulation of Hole Concentration and Mobility and First-Principle Analysis of Mg-Doping in InGaN Grown by MOCVD

Materials ◽

10.3390/ma14185339 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5339

Author(s):

Lian Zhang ◽

Rong Wang ◽

Zhe Liu ◽

Zhe Cheng ◽

Xiaodong Tong ◽

...

Keyword(s):

First Principles ◽

Metalorganic Chemical Vapor Deposition ◽

Hole Concentration ◽

Chemical Vapor ◽

Hole Mobility ◽

Nitrogen Vacancy ◽

First Principle ◽

Mg Doping ◽

Limiting Condition ◽

P Type

This work studied the regulation of hole concentration and mobility in p-InGaN layers grown by metalorganic chemical vapor deposition (MOCVD) under an N-rich environment. By adjusting the growth temperature, the hole concentration can be controlled between 6 × 1017/cm3 and 3 × 1019/cm3 with adjustable hole mobility from 3 to 16 cm2/V.s. These p-InGaN layers can meet different requirements of devices for hole concentration and mobility. First-principles defect calculations indicate that the p-type doping of InGaN at the N-rich limiting condition mainly originated from Mg substituting In (MgIn). In contrast with the compensation of nitrogen vacancy in p-type InGaN grown in a Ga-rich environment, the holes in p-type InGaN grown in an N-rich environment were mainly compensated by interstitial Mg (Mgi), which has very low formation energy.

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Electrical and Optical Properties of Carbon Doped Cubic GaN Epilayers Grown Under Extreme Ga Excess

MRS Proceedings ◽

10.1557/proc-798-y8.2 ◽

2003 ◽

Vol 798 ◽

Cited By ~ 2

Author(s):

D. J. As ◽

D. G. Pacheco-Salazar ◽

S. Potthast ◽

K. Lischka

Keyword(s):

Optical Properties ◽

Hole Concentration ◽

Hole Mobility ◽

Growth Conditions ◽

Rf Plasma ◽

Electrical And Optical Properties ◽

Carbon Doped ◽

Cubic Gan ◽

Hall Effect Measurements ◽

P Type

ABSTRACTP-type doping of cubic GaN by carbon is reported with maximum hole concentration of 2 6.1×1018cm-3and hole mobility of 23.5 cm /Vs at room temperature, respectively. The cubic GaN:C was grown by rf-plasma assisted molecular beam epitaxy (MBE) under Ga-rich growth conditions on a semiinsulating GaAs (001) substrate (3 inches wafer). E-beam evaporation of a graphite rode with an C-flux of 1×1012cm-2s-1was used for C-doping of the c-GaN. Optical microscopy, Hall-effect measurements and photoluminescence were performed to investigate the morphological, electrical and optical properties of cubic GaN:C. Under Ga-rich growth conditions most part of the carbon atoms were incorporated substitutially on N-site giving p-type conductivity. Our results verify that effective p-type doping of c-GaN can be achieved under extrem Ga excess.

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Zinc Oxide Thin Films with Reduced Native Compensative Defects Grown by Ultrasonic Spray Pyrolysis at Atmosphere

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.589 ◽

2007 ◽

Vol 336-338 ◽

pp. 589-592

Author(s):

Jian Ling Zhao ◽

Xiao Min Li ◽

Ji Ming Bian ◽

Wei Dong Yu ◽

C.Y. Zhang

Keyword(s):

Spray Pyrolysis ◽

Deep Level ◽

Hole Concentration ◽

Ultrasonic Spray Pyrolysis ◽

Zno Films ◽

Near Band Edge ◽

Dense Microstructure ◽

Ultrasonic Spray ◽

High Hole Concentration ◽

P Type

ZnO films were deposited on Si (100) substrate by ultrasonic spray pyrolysis at atmosphere. The film grown at optimum conditions is well crystallized with uniform, smooth and dense microstructure. Photoluminescence measurement shows a strong near band edge UV emission at 379nm and an almost undetectable deep-level emission band centered at 502nm. The resistivity of ZnO film is reduced by an order after N-In codoping, which produces p-type conduction with high hole concentration and hall mobility.

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