Impurity Compensation

Marfaing, Y.

doi:10.1016/b978-0-08-046409-1.00007-1

Cited by 3 publications

(1 citation statement)

References 83 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During cooling to room temperature native defects are supposed to migrate and interact with charged impurities. As a result, various types of associates and precipitates are formed 58 59 . The remaining isolated mostly annihilate during cooling at surface or dislocations and the final room temperature density of comes out very low 42 .…”

Section: Resultsmentioning

confidence: 99%

Positron annihilation spectroscopy of vacancy-related defects in CdTe:Cl and CdZnTe:Ge at different stoichiometry deviations

Šedivý

Čı́žek

Belas

et al. 2016

Sci Rep

View full text Add to dashboard Cite

Positron annihilation spectroscopy (PAS) was used to examine the effect of defined Cd-rich and Te-rich annealing on point defects in Cl-doped CdTe and Ge-doped CdZnTe semi-insulating single crystals. The as-grown crystals contain open-volume defects connected with Cd vacancies . It was found that the Cd vacancies agglomerate into clusters coupled with Cl in CdTe:Cl, and in CdZnTe:Ge they are coupled with Ge donors. While annealing in Cd pressure reduces of the density, subsequent annealing in Te pressure restores . The CdTe:Cl contains negatively-charged shallow traps interpreted as Rydberg states of A-centres and representing the major positron trapping sites at low temperature. Positrons confined in the shallow traps exhibit lifetime, which is shorter than the CdTe bulk lifetime. Interpretation of the PAS data was successfully combined with electrical resistivity, Hall effect measurements and chemical analysis, and allowed us to determine the principal point defect densities.

show abstract

Section: Resultsmentioning

confidence: 99%

Positron annihilation spectroscopy of vacancy-related defects in CdTe:Cl and CdZnTe:Ge at different stoichiometry deviations

Šedivý

Čı́žek

Belas

et al. 2016

Sci Rep

View full text Add to dashboard Cite

show abstract

Properties of a highly compensated high-purity germanium

Palleti,

Seyidov,

Gybin

et al. 2024

J Mater Sci: Mater Electron

View full text Add to dashboard Cite

The electrical and optical properties of a compensated high-purity germanium (HPGe) single crystal was investigated using various characterization techniques. Aluminium, boron, and phosphorus were the major residual shallow-level impurities identified by photothermal ionization spectroscopy (PTIS). Hall effect measurements performed at low temperatures (77 K) along the growth length reveal that the crystal is p-type at the top and bottom, while n-type in the middle part with a net carrier concentration in the range of 1010–1011 cm−3. The obtained very high resistivity (2.3 ⨯ 108 Ω·cm) at 91 K in the temperature-dependent Hall measurements (TDH) at the bottom part of the crystal indicates a high level of compensation (84%) of charge carriers by deep-level impurities or defects with an activation energy near 0.195 eV. The highest hole mobility$$({\mu _p} = ~46700\,{\rm{c}}{{\rm{m}}^2}\,/{\rm{V}}\cdot{\rm{s}})$$ ( μ p = 46700 c m 2 / V · s ) at 77 K was obtained at the top part, which is moderately compensated. The carrier lifetimes of the grown HPGe crystals were measured using microwave-detected photoconductivity (MDP) at room temperature. The average carrier lifetime decreases from the top to bottom part of the crystal from 130 to 60 µs, which is less than that of the usually observed values in HPGe crystals due to a strong compensation.

show abstract

Self-compensation in arsenic doping of CdTe

Ablekim

Swain

Yin

et al. 2017

Sci Rep

View full text Add to dashboard Cite

Efficient p-type doping in CdTe has remained a critical challenge for decades, limiting the performance of CdTe-based semiconductor devices. Arsenic is a promising p-type dopant; however, reproducible doping with high concentration is difficult and carrier lifetime is low. We systematically studied defect structures in As-doped CdTe using high-purity single crystal wafers to investigate the mechanisms that limit p-type doping. Two As-doped CdTe with varying acceptor density and two undoped CdTe were grown in Cd-rich and Te-rich environments. The defect structures were investigated by thermoelectric-effect spectroscopy (TEES), and first-principles calculations were used for identifying and assigning the experimentally observed defects. Measurements revealed activation of As is very low in both As-doped samples with very short lifetimes indicating strong compensation and the presence of significant carrier trapping defects. Defect studies suggest two acceptors and one donor level were introduced by As doping with activation energies at ~88 meV, ~293 meV and ~377 meV. In particular, the peak shown at ~162 K in the TEES spectra is very prominent in both As-doped samples, indicating a signature of AX-center donors. The AX-centers are believed to be responsible for most of the compensation because of their low formation energy and very prominent peak intensity in TEES spectra.

show abstract

Impurity Compensation

Cited by 3 publications

References 83 publications

Positron annihilation spectroscopy of vacancy-related defects in CdTe:Cl and CdZnTe:Ge at different stoichiometry deviations

Positron annihilation spectroscopy of vacancy-related defects in CdTe:Cl and CdZnTe:Ge at different stoichiometry deviations

Properties of a highly compensated high-purity germanium

Self-compensation in arsenic doping of CdTe

Contact Info

Product

Resources

About