Influence of deep level intrinsic defects on the carrier transport in p-type Hg1-xCdxTe

The paper presents the results of the study of charge carrier transport and deep level recharging in semiconductor structures for ionizing radiation detectors. The resistive gallium arsenide structures with Schottky barriers and a uniform distribution of the deep chromium acceptor and the deep EL2 donor centers were studied. The effect of depletion of the volume of detector structures with electrons has been found by solving the continuity and Poisson equations with the use of a commercial software. It is found that the nonlinearity of the current-voltage characteristics of the structures is associated with change in the conductivity type under transition from an equilibrium to a nonequilibrium state. In this case, the structures with the initial equilibrium p-type conductivity have current-voltage characteristics close to linear.

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Spectrum of Defect States in Porous Organic Low-k Dielectric Films, Annealed in Argon and Nitrogen

MRS Proceedings ◽

10.1557/proc-766-e8.5 ◽

2003 ◽

Vol 766 ◽

Author(s):

V. Ligatchev ◽

T.K.S. Wong ◽

T.K. Goh ◽

Rusli Suzhu Yu

Keyword(s):

Deep Level ◽

Dielectric Films ◽

Silicon Substrates ◽

Reverse Bias Voltage ◽

Defect States ◽

Single Side ◽

Sandwich Type ◽

Transient Spectroscopy ◽

P Type ◽

Spectrum Deconvolution

AbstractDefect spectrum N(E) of porous organic dielectric (POD) films is studied with capacitance deep-level-transient-spectroscopy (C-DLTS) in the energy range up to 0.7 eV below conduction band bottom Ec. The POD films were prepared by spin coating onto 200mm p-type (1 – 10 Δcm) single-side polished silicon substrates followed by baking at 325°C on a hot plate and curing at 425°C in furnace. The film thickness is in the 5000 – 6000 Å range. The ‘sandwich’ -type NiCr/POD/p-Si/NiCr test structures showed both rectifying DC current-voltage characteristics and linear 1/C2 vs. DC reverse bias voltage. These confirm the applicability of the C-DLTS technique for defect spectrum deconvolution and the n-type conductivity of the studied films. Isochronal annealing (30 min in argon or 60 min in nitrogen) has been performed over the temperature range 300°C - 650°C. The N(E) distribution is only slightly affected by annealing in argon. However, the distribution depends strongly on the annealing temperature in nitrogen ambient. A strong N(E) peak at Ec – E = 0.55 – 0.60 eV is detected in all samples annealed in argon but this peak is practically absent in samples annealed in nitrogen at Ta < 480°C. On the other hand, two new peaks at Ec – E = 0.12 and 0.20 eV appear in the N(E) spectrum of the samples annealed in nitrogen at Ta = 650°C. The different features of the defect spectrum are attributed to different interactions of argon and nitrogen with dangling carbon bonds on the intra-pore surfaces.

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Theory of Intrinsic Defects in Crystalline GeTe and of Their Role in Free Carrier Transport Novel Materials and Device Research

10.21236/ada479287 ◽

2008 ◽

Author(s):

Arthur H. Edwards

Keyword(s):

Carrier Transport ◽

Free Carrier ◽

Intrinsic Defects ◽

Novel Materials ◽

Device Research

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Temperature dependency and carrier transport mechanisms of Ti/p-type InP Schottky rectifiers

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2010.05.074 ◽

2010 ◽

Vol 504 (1) ◽

pp. 146-150 ◽

Cited By ~ 70

Author(s):

V. Janardhanam ◽

Hoon-Ki Lee ◽

Kyu-Hwan Shim ◽

Hyo-Bong Hong ◽

Soo-Hyung Lee ◽

...

Keyword(s):

Carrier Transport ◽

Temperature Dependency ◽

Transport Mechanisms ◽

Schottky Rectifiers ◽

P Type

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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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Comparison of deep level spectra in p-type and n-type GaN grown by molecular beam epitaxy [phys. stat. sol. (b) 244, No. 6, 1867–1871 (2007)]

physica status solidi (b) ◽

10.1002/pssb.200740116 ◽

2007 ◽

Vol 244 (12) ◽

pp. 4692-4692

Author(s):

A. Armstrong ◽

A. Corrion ◽

C. Poblenz ◽

U. K. Mishra ◽

J. S. Speck ◽

...

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Deep Level ◽

P Type

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Characteristics of P-Type and N-Type Photoelectrochemical Biosensors: A Case Study for Esophageal Cancer Detection

Nanomaterials ◽

10.3390/nano11051065 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1065

Author(s):

Joseph-Hang Leung ◽

Hong-Thai Nguyen ◽

Shih-Wei Feng ◽

Sofya B. Artemkina ◽

Vladimir E. Fedorov ◽

...

Keyword(s):

Esophageal Cancer ◽

Cancer Cells ◽

Carrier Transport ◽

X Ray Diffraction ◽

Photoelectrochemical Response ◽

Carrier Separation ◽

Human Esophageal Cancer ◽

P Type ◽

Esophageal Cancer Cells

P-type and N-type photoelectrochemical (PEC) biosensors were established in the laboratory to discuss the correlation between characteristic substances and photoactive material properties through the photogenerated charge carrier transport mechanism. Four types of human esophageal cancer cells (ECCs) were analyzed without requiring additional bias voltage. Photoelectrical characteristics were examined by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–vis reflectance spectroscopy, and photocurrent response analyses. Results showed that smaller photocurrent was measured in cases with advanced cancer stages. Glutathione (L-glutathione reduced, GSH) and Glutathione disulfide (GSSG) in cancer cells carry out redox reactions during carrier separation, which changes the photocurrent. The sensor can identify ECC stages with a certain level of photoelectrochemical response. The detection error can be optimized by adjusting the number of cells, and the detection time of about 5 min allowed repeated measurement.

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