About the Hole Transport Analysis in Heavy Doped p-Type 4H-SiC(Al)

The knowledge of the Hall factor is essential to convert Hall todrifttransport data, in order to fit them and reliably evaluate doping and compensation levels of samples. By introducing empirical mass anisotropy factors, reasons were given in favour of a generalized use of the unique experimental evaluation of the Hall factor reported by the literature forp-type 4H-SiC, which has been assessed for an Al acceptor density in the range of 1.8×1015- 2×1018cm-3. Using such a curve, carrier transport data, taken in Al+implanted 4H-SiC for an Al concentration of 5×1019cm-3after either 2000°C/30s microwave annealing or 1950°C/300s conventional annealing, were analysed through a standard relaxation time approximation model. A slight difference was evidenced in the compensation level of the samples, also resulting in a different ionization energy of the acceptor.

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Analysis of hole transport in cubic phase of p-type GaN by relaxation time approximation

Physica B Condensed Matter ◽

10.1016/s0921-4526(99)00280-x ◽

1999 ◽

Vol 272 (1-4) ◽

pp. 256-259

Author(s):

Y Hayashi

Keyword(s):

Relaxation Time ◽

Hole Transport ◽

Cubic Phase ◽

Time Approximation ◽

Relaxation Time Approximation ◽

P Type

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Electrical Properties of p-Type In-Situ Doped vs. Al-Implanted 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.483-485.401 ◽

2005 ◽

Vol 483-485 ◽

pp. 401-404 ◽

Cited By ~ 3

Author(s):

Julien Pernot ◽

Sylvie Contreras ◽

Jean Camassel ◽

Jean-Louis Robert

Keyword(s):

Relaxation Time ◽

Electrical Properties ◽

Temperature Dependence ◽

Hall Mobility ◽

Hole Concentration ◽

Detailed Comparison ◽

Time Approximation ◽

Relaxation Time Approximation ◽

P Type

We report a detailed investigation of the electrical properties of p-type 4H-SiC. In the range 100 K-800 K we show that, both, the temperature dependence of the hole concentration and Hall mobility is satisfactorily described using the relaxation time approximation. Performing a detailed comparison of in-situ vs. implantation doping, we evidence an incomplete activation of the dose (about 50 ±10 %) with apparition of a large number of compensating centres in the implanted layers.

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Sb deficiencies control hole transport and boost the thermoelectric performance of p-type AgSbSe2

Journal of Materials Chemistry C ◽

10.1039/c5tc01429h ◽

2015 ◽

Vol 3 (40) ◽

pp. 10415-10421 ◽

Cited By ~ 11

Author(s):

Satya N. Guin ◽

Kanishka Biswas

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

Carrier Transport ◽

Hole Transport ◽

Thermoelectric Performance ◽

Low Thermal Conductivity ◽

New Strategy ◽

P Type

We demonstrate a new strategy to control the carrier transport in AgSbSe2by introducing Sb deficiencies. Enhanced electrical conductivity and ultra-low thermal conductivity resulted a peak ZT value ∼1 at 610 K in Sb deficient AgSbSe2.

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Charge Sharing and Charge Loss in High-Flux Capable Pixelated CdZnTe Detectors

Sensors ◽

10.3390/s21093260 ◽

2021 ◽

Vol 21 (9) ◽

pp. 3260

Author(s):

Kjell A. L. Koch-Mehrin ◽

Sarah L. Bugby ◽

John E. Lees ◽

Matthew C. Veale ◽

Matthew D. Wilson

Keyword(s):

Carrier Transport ◽

Hole Transport ◽

Uniform Electric Field ◽

Photon Flux ◽

High Flux ◽

Charge Sharing ◽

Cdte Detector ◽

Charge Loss ◽

Cdznte Detectors ◽

Detector Model

Cadmium zinc telluride (CdZnTe) detectors are known to suffer from polarization effects under high photon flux due to poor hole transport in the crystal material. This has led to the development of a high-flux capable CdZnTe material (HF-CdZnTe). Detectors with the HF-CdZnTe material have shown promising results at mitigating the onset of the polarization phenomenon, likely linked to improved crystal quality and hole carrier transport. Better hole transport will have an impact on charge collection, particularly in pixelated detector designs and thick sensors (>1 mm). In this paper, the presence of charge sharing and the magnitude of charge loss were calculated for a 2 mm thick pixelated HF-CdZnTe detector with 250 μm pixel pitch and 25 μm pixel gaps, bonded to the STFC HEXITEC ASIC. Results are compared with a CdTe detector as a reference point and supported with simulations from a Monte-Carlo detector model. Charge sharing events showed minimal charge loss in the HF-CdZnTe, resulting in a spectral resolution of 1.63 ± 0.08 keV Full Width at Half Maximum (FWHM) for bipixel charge sharing events at 59.5 keV. Depth of interaction effects were shown to influence charge loss in shared events. The performance is discussed in relation to the improved hole transport of HF-CdZnTe and comparison with simulated results provided evidence of a uniform electric field.

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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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Damping effects in doped graphene: The relaxation-time approximation

Physical Review B ◽

10.1103/physrevb.90.205426 ◽

2014 ◽

Vol 90 (20) ◽

Cited By ~ 16

Author(s):

I. Kupčić

Keyword(s):

Relaxation Time ◽

Time Approximation ◽

Relaxation Time Approximation ◽

Doped Graphene ◽

Damping Effects

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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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