Photoluminescence analysis of shallow acceptor in CdTe films on GaAs(100) substrates

Effects of compressive stress on oxygen agglomeration processes in Czochralski grown silicon heat treated at T= 450OC, used as a reference temperature, and T= 600OC to 800OC are investigated in some detail. Compressive stresses of about P= 1 GPa lead to enhanced formation of Thermal Double Donors in materials annealed over a temperature range of T= 450OC – 600OC. It has been shown that the formation of thermal donors at T= 450OC under normal conditions and compressive stress is accompanied with loss of substitutional boron. In contrast, the concentration of the shallow acceptor states of substitutional boron in silicon annealed under stress at T≥ 600OC remains constant. An enhancement effect of thermal donor formation is gradually weakened at T≥ 700OC. The oxygen diffusivity sensitive to mechanical stress is believed to be responsible for the observed effects in heat-treated silicon.

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Evidence for oxygen being a dominant shallow acceptor in p-type CuI

APL Materials ◽

10.1063/5.0047723 ◽

2021 ◽

Vol 9 (5) ◽

pp. 051101

Author(s):

P. Storm ◽

S. Gierth ◽

S. Selle ◽

M. S. Bar ◽

H. von Wenckstern ◽

...

Keyword(s):

Shallow Acceptor ◽

P Type

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Effect of MgCl2 passivation on Bi incorporated CdTe absorber films: Alternative to CdCl2 passivation on Cu incorporated CdTe films

10.1063/5.0052887 ◽

2021 ◽

Author(s):

Himanshu ◽

S. L. Patel ◽

A. Thakur ◽

M. S. Dhaka

Keyword(s):

Cdte Films

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Imaging CdCl2 defect passivation and formation in polycrystalline CdTe films by cathodoluminescence

Physical Review Materials ◽

10.1103/physrevmaterials.5.064601 ◽

2021 ◽

Vol 5 (6) ◽

Author(s):

Thomas Bidaud ◽

John Moseley ◽

Mahisha Amarasinghe ◽

Mowafak Al-Jassim ◽

Wyatt K. Metzger ◽

...

Keyword(s):

Defect Passivation ◽

Cdte Films

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Anomalous Photovoltaic Effect in CdTe Films Obliquely Deposited in Vacuum

Journal of Optics ◽

10.1007/bf03549057 ◽

1982 ◽

Vol 11 (4) ◽

pp. 81-83

Author(s):

O. Abd El-Halim ◽

A. A. El-Shazly ◽

H. T. El-Shair ◽

M. K. El-Mously

Keyword(s):

Photovoltaic Effect ◽

Cdte Films

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Preparation and Properties of CdTe Films on Mo/Glass Substrates

MRS Proceedings ◽

10.1557/proc-1165-m08-24 ◽

2009 ◽

Vol 1165 ◽

Author(s):

Vello Valdna ◽

Maarja Grossberg ◽

Hiie Jaan ◽

Urve Kallavus ◽

Valdek Mikli ◽

...

Keyword(s):

Cadmium Chloride ◽

Radiation Detectors ◽

Cdte Film ◽

Chloride Flux ◽

Type Conductivity ◽

Coated Glass ◽

Glass Substrates ◽

Group I ◽

Cdte Films ◽

P Type

AbstractShort-bandgap group II-VI compound cadmium telluride is widely used for the infrared optics, radiation detectors, and solar cells where p-type CdTe is needed. p-type conductivity of CdTe is mainly caused by the chlorine-based A-centers, and in part, by the less stable copper-oxygen complexes. As a rule, CdTe films are recrystallized by the help of a cadmium chloride flux that saturates CdTe with chlorine. In chlorine-saturated CdTe A-centers are converted to isoelectronic complexes that cause resistivity increasement of CdTe up to 9 orders of magnitude. Excess copper and oxygen or group I elements as sodium also deteriorate the p-type conductivity of CdTe like excess chlorine. p-type conductivity of CdTe can be restored e.g. by the vacuum annealing which removes excess chlorine from the film. Unfortunately, treatment that betters p-type conductivity of the CdTe film degrades the junction of the superstrate configuration cells. In this work we investigate possibilities to prepare p-type CdTe films on the molybdenum coated glass substrates. Samples were prepared by the vacuum evaporation and dynamic recrystallization of 6N purity CdTe on the top of Mo-coated glass substrates. Then samples were recrystallized with cadmium chloride flux under tellurium vapour pressure. Results of the test studies on the structure and electronic parameters of samples are presented and discussed.

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Deep Level Related Yellow Luminescence in P-Type GaN Grown by MBE on (0001) Sapphire

MRS Proceedings ◽

10.1557/proc-595-f99w11.50 ◽

1999 ◽

Vol 595 ◽

Cited By ~ 1

Author(s):

Giancarlo Salviati ◽

Nicola Armani ◽

Carlo Zanotti-Fregonara ◽

Enos Gombia ◽

Martin Albrecht ◽

...

Keyword(s):

Volume Fraction ◽

Deep Level ◽

Cubic Phase ◽

Donor Level ◽

Yellow Luminescence ◽

Wurtzite Phase ◽

Shallow Acceptor ◽

Deep Donor ◽

P Type ◽

Deep Donor Level

AbstractYellow luminescence (YL) has been studied in GaN:Mg doped with Mg concentrations ranging from 1019 to 1021 cm−3 by spectral CL (T=5K) and TEM and explained by suggesting that a different mechanism could be responsible for the YL in p-type GaN with respect to that acting in n-type GaN.Transitions at 2.2, 2.8, 3.27, 3.21, and 3.44 eV were found. In addition to the wurtzite phase, TEM showed a different amount of the cubic phase in the samples. Nano tubes with a density of 3×109 cm−2 were also observed by approaching the layer/substrate interface. Besides this, coherent inclusions were found with a diameter in the nm range and a volume fraction of about 1%.The 2.8 eV transition was correlated to a deep level at 600 meV below the conduction band (CB) due to MgGa-VN complexes. The 3.27 eV emission was ascribed to a shallow acceptor at about 170-190 meV above the valence band (VB) due to MgGa.The 2.2 eV yellow band, not present in low doped samples, increased by increasing the Mg concentration. It was ascribed to a transition between a deep donor level at 0.8-1.1 eV below the CB edge due to NGa and the shallow acceptor due to MgGa. This assumption was checked by studying the role of C in Mg compensation. CL spectra from a sample with high C content showed transitions between a C-related 200 meV shallow donor and a deep donor level at about 0.9- 1.1 eV below the CB due to a NGa-VN complex. In our hypothesis this should induce a decrease of the integrated intensity in both the 2.2 and 2.8 eV bands, as actually shown by CL investigations.

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