Behavior of Electron Traps Induced by Phosphidization and Nitridation of GaAs Surfaces

1998 ◽  
Vol 510 ◽  
Author(s):  
Satoshi Nozu ◽  
Koichiro Matsuda ◽  
Takashi Sugino
Keyword(s):  
Energy Level ◽  
Cross Section ◽  
Capture Cross Section ◽  
Conduction Band Edge ◽  
Capture Cross ◽  
Electron Traps ◽  
Plasma Treatments ◽  
Transient Spectroscopy ◽  
Capacitance Transient ◽  
Isothermal Capacitance Transient Spectroscopy

AbstractGaAs is treated with remote PH3 and N2 plasmas. Electron traps induced by plasma treatments are investigated by isothermal capacitance transient spectroscopy measurements. The EL2 trap is detected in the as-grown GaAs. The TP1 trap(Ec-0.26eV) is generated in GaAs phosphidized for 10min, while the TN1 trap(Ec-0.66eV) is induced in GaAs nitrided for 30min. It is found that the TP1 trap is changed to the another trap with an energy level as shallow as 0.16eV below the conduction band edge and a capture cross section as small as 1.8×10−21cm2 by treating with N2 plasma subsequently after PH3 plasma treatment.

Interpretation of The a-Si:H DLTS and ICTS Experimental Data

1986 ◽  
Vol 70 ◽  
Author(s):  
Ru-Qi Han ◽  
K. L. Ngai ◽  
J. Ruvalds
Keyword(s):  
Cross Section ◽  
Relaxation Function ◽  
Capture Cross Section ◽  
Coupling Model ◽  
Energy Scale ◽  
Electronic Density ◽  
Transient Spectroscopy ◽  
Capacitance Transient ◽  
Isothermal Capacitance Transient Spectroscopy ◽  
Additional Prediction

ABSTRACTThe isothermal capacitance transient spectroscopy (ICTS) data of a- Si:H is consistently analyzed in terms of a relaxation function with a fractional exponential time decay of the form φ(t)=exp[-(t/τ*)λ] with λ≅0.8. The anomalous variation of the effective relaxation time τ* (and hence that of the attempt-to-escape frequency ν* and the capture cross section σ* observed by Okushi and coworkers) with energy and temperature is shown to follow an additional prediction of the time dependent relaxation rate coupling model developed by Ngai and coworkers for relaxations in many complex systems. A modified energy scale is extended from the ICTS analysis which brings its electronic density of states structure in closer agreement with results obtained by DLTS experiments.

Effect of Sacrificial AlN (Aluminum Nitride) Layer on the Deep Surface States of 4H-SiC

2021 ◽  
Vol 21 (3) ◽  
pp. 1904-1908
Author(s):  
Woo-Young Son ◽  
Jeong Hyun Moon ◽  
Wook Bahng ◽  
Sang-Mo Koo
Keyword(s):  
Cross Section ◽  
Deep Level Transient Spectroscopy ◽  
Capture Cross Section ◽  
Deep Level ◽  
Surface States ◽  
Nitride Layer ◽  
Double Negative ◽  
Capture Cross ◽  
Trap Energy ◽  
Transient Spectroscopy

We investigated the effect of a sacrificial AlN layer on the deep energy level states of 4H-SiC surface. The samples with and without AlN layer have been annealed at 1300 °C for 30 minutes duration using a tube furnace. After annealing the samples, the changes of the carbon vacancy (VC) related Z1/2 defect characteristics were analyzed by deep level transient spectroscopy. The trap energy associated with double negative acceptor (VC(2-/0)) appears at ˜0.7 eV and was reduced from ˜0.687 to ˜0.582 eV in the sacrificial AlN layer samples. In addition, the capture cross section was significantly improved from ˜2.1×10-14 to ˜3.8×10−16 cm−2 and the trap concentration was reduced by approximately 40 times.

DLTS Study on Al+ Ion Implanted and 1950°C Annealed p-i-n 4H-SiC Vertical Diodes

2017 ◽  
Vol 897 ◽  
pp. 279-282 ◽  
Author(s):  
Hussein M. Ayedh ◽  
Maurizio Puzzanghera ◽  
Bengt Gunnar Svensson ◽  
Roberta Nipoti
Keyword(s):  
Cross Section ◽  
Deep Level Transient Spectroscopy ◽  
Capture Cross Section ◽  
Deep Level ◽  
Electron Trap ◽  
Double Negative ◽  
Capture Cross ◽  
Carrier Traps ◽  
Transient Spectroscopy ◽  
Post Implantation

A vertical 4H-SiC p-i-n diode with 2×1020cm-3 Al+ implanted emitter and 1950°C/5min post implantation annealing has been characterized by deep level transient spectroscopy (DLTS). Majority (electron) and minority (hole) carrier traps have been found. Electron traps with a homogeneous depth profile, are positioned at 0.16, 0.67 and 1.5 eV below the minimum edge of the conduction band, and have 3×10-15, 1.7×1014, and 1.8×10-14 cm2 capture cross section, respectively. A hole trap decreasing in intensity with decreasing pulse voltage occurs at 0.35 eV above the maximum edge of the valence band with 1×1013 cm2 apparent capture cross section. The highest density is observed for the refractory 0.67 eV electron trap that is due to the double negative acceptor states of the carbon vacancy.

scholarly journals Extracting bulk defect parameters in silicon wafers using machine learning models

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Yoann Buratti ◽  
Quoc Thong Le Gia ◽  
Josef Dick ◽  
Yan Zhu ◽  
Ziv Hameiri
Keyword(s):  
Machine Learning ◽  
Energy Level ◽  
Cross Section ◽  
Capture Cross Section ◽  
Complex Data ◽  
Capture Cross ◽  
Cross Section Ratio ◽  
Defect Energy ◽  
Section Ratio ◽  
The Impact

Abstract The performance of high-efficiency silicon solar cells is limited by the presence of bulk defects. Identification of these defects has the potential to improve cell performance and reliability. The impact of bulk defects on minority carrier lifetime is commonly measured using temperature- and injection-dependent lifetime spectroscopy and the defect parameters, such as its energy level and capture cross-section ratio, are usually extracted by fitting the Shockley-Read-Hall equation. We propose an alternative extraction approach by using machine learning trained on more than a million simulated lifetime curves, achieving coefficient of determinations between the true and predicted values of the defect parameters above 99%. In particular, random forest regressors, show that defect energy levels can be predicted with a high precision of ±0.02 eV, 87% of the time. The traditional approach of fitting to the Shockley-Read-Hall equation usually yields two sets of defect parameters, one in each half bandgap. The machine learning model is trained to predict the half bandgap location of the energy level, and successfully overcome the traditional approach’s limitation. The proposed approach is validated using experimental measurements, where the machine learning predicts defect energy level and capture cross-section ratio within the uncertainty range of the traditional fitting method. The successful application of machine learning in the context of bulk defect parameter extraction paves the way to more complex data-driven physical models which have the potential to overcome the limitation of traditional approaches and can be applied to other materials such as perovskite and thin film.

Interface States in 4H- and 6H-SiC MOS Capacitors: A Comparative Study between Conductance Spectroscopy and Thermal Dielectric Relaxation Current Technique

2009 ◽  
Vol 615-617 ◽  
pp. 497-500 ◽  
Author(s):  
Lars S. Løvlie ◽  
Ioana Pintilie ◽  
S. Kumar C.P. ◽  
Ulrike Grossner ◽  
Bengt Gunnar Svensson ◽  
...  
Keyword(s):  
Comparative Study ◽  
Dielectric Relaxation ◽  
Cross Section ◽  
Capture Cross Section ◽  
Interface States ◽  
Conduction Band Edge ◽  
Capture Cross ◽  
Mos Capacitors ◽  
Dry Oxidation ◽  
Good Agreement

The purpose of this work is to compare the density of shallow interface states (Dit) at the interface of SiO2/SiC MOS capacitors as deducted by the conductance spectroscopy (CS) and thermally dielectric relaxation current (TDRC) techniques. Both capacitors of 4H- and 6H-SiC (n-type) are investigated, and both ordinary dry oxidation and an improved industrial procedure have been employed. The two techniques are found to give rather good agreement for interface states located ≥0.3 eV below the conduction band edge (Ec) while for more shallow states vastly different distributions of Dit are obtained. Different reasons for these contradictory results are discussed, such as strong temperature and energy dependence of the capture cross section of the shallow interface states.

Effect of NO Annealing on 6H- and 4H-SiC MOS Interface States

2010 ◽  
Vol 645-648 ◽  
pp. 499-502 ◽  
Author(s):  
Alberto F. Basile ◽  
John Rozen ◽  
X.D. Chen ◽  
Sarit Dhar ◽  
John R. Williams ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Cross Section ◽  
Deep Level Transient Spectroscopy ◽  
Capture Cross Section ◽  
Deep Level ◽  
Capture Cross ◽  
Temperature Dependent ◽  
Band Energy ◽  
Transient Spectroscopy ◽  
Semiconductor Traps

The electrical properties of the SiC/SiO2 interface resulting from oxidation of the n-type 6H-SiC polytype were studied by hi-lo CV, temperature dependent CV and constant capacitance deep level transient spectroscopy (CCDLTS) techniques. Several trap species differing in energy and capture cross section were identified. A trap distribution at 0.5 eV below the 6H-SiC conduction band energy and a shallower density of states in both the 6H and 4H polytyes are passivated by post-oxidation NO annealing. However, other ultra-shallow and deeper defect distributions remain after nitridation. The latter may originate from semiconductor traps.

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