Non-Equilibrium Acceptor Concentration in GaN:Mg Grown by Metalorganic Chemical Vapor Deposition

ABSTRACTIt is shown that the high p-type conductivity in GaN:Mg, grown by metal-organic chemical vapor deposition followed by post-growth annealing, is due to non-equilibrium acceptor concentrations. A series of samples cut from a single GaN:Mg wafer, which initially had undergone rapid thermal annealing (RTA) after growth, has been investigated. The samples were annealed at various temperatures in nitrogen ambient for over 12 hours, and temperature-dependent Hall effect measurements were performed. For samples annealed at temperatures higher than 850 °C, the hole concentrations decrease by at least an order of magnitude, compared with the original sample. This behavior is explained by an Mg acceptor concentration in excess of its equilibrium solubility limit in the original sample; thus, at high enough temperatures, in the absence of hydrogen, Mg acceptors diffuse either to form electrically inactive precipitates or are eliminated. It is worth noting that the acceptor activation energy remains the same for all samples.

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The Growth and Doping of Al(As)Sb by Metal-Organic Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-421-33 ◽

1996 ◽

Vol 421 ◽

Author(s):

R. M. Biefeld ◽

A. A. Allerman ◽

S. R. Kurtz

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Active Regions ◽

Epitaxial Films ◽

Organic Chemical ◽

Order Of Magnitude ◽

Metal Organic ◽

Organic Chemical Vapor Deposition ◽

Cladding Layers

AbstractAlSb and AlAsxSb1−x epitaxial films grown by metal-organic chemical vapor deposition were successfully doped p- or n-type using diethylzinc or tetraethyltin, respectively. AlSb films were grown at 500°C and 76 torr using trimethylamine or ethyldimethylamine alane and triethylantimony. We examined the growth of AlAsSb using temperatures of 500 to 600 ° C, pressures of 65 to 630 torr, V/Ill ratios of 1–17, and growth rates of 0.3 to 2.7 μm/hour in a horizontal quartz reactor. SIMS showed C and 0 levels below 2 × 1018 cm−3 and 6×1018 cm−3 respectively for undoped AlSb. Similar levels of O were found in AlAs0.16Sb0.84 films but C levels were an order of magnitude less in undoped and Sn-doped AlAs0.16 Sb0.84 films. Hall measurements of AlAs0.16Sb0.84 showed hole concentrations between l×1017 cm−3 to 5×1018 cm−3 for Zn-doped material and electron concentrations in the low to mid 1018 cm−3 for Sndoped material. We have grown pseudomorphic InAs/InAsSb quantum well active regions on AlAsSb cladding layers. Photoluminescence of these layers has been observed up to 300 K.

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Characteristics of Doping and Diffusion of Heavily Doped N and P type InP and InGaAs Epitaxial Layers grown by Metal Organic Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-163-867 ◽

1989 ◽

Vol 163 ◽

Cited By ~ 2

Author(s):

C.J. Pinzone ◽

N. T. Ha ◽

N. D. Gerrard ◽

R. D. Dupuis ◽

H. S. Luftman

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Effective Diffusion ◽

Chemical Vapor ◽

Solubility Limit ◽

Organic Chemical ◽

Device Applications ◽

Metal Organic ◽

P Type ◽

High Degree

AbstractElectronic and photonic device applications of the InGaAs/InP materials system often require the growth of epitaxial material doped to or near the solubility limit of the impurity in the host material. These requirements present an extreme challenge for the crystal grower. To produce devices with abrupt dopant profiles, preserve the junction during subsequent growth, and retain a high degree of crystalline perfection, it is necessary to understand the limits of dopant incorporation and the behavior of the impurity in the material.In this study, N-type doping above 1019 cm-3 has been achieved in InP and InGaAs using Sn as a dopant P-type Zn doping at these levels has also been achieved in these materials but p type activation above ~3 × 1018 cm-3 in InP has not been seen. All materials were grown by the metalorganic chemical vapor deposition (MOCVD) crystal growth technique. Effective diffusion coefficients have been measured for Zn and Sn in both materials from analysis of secondary ion mass spectra (SIMS) of specially grown and annealed samples.

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