Detection of minority carrier traps in p-type 4H-SiC

G. Alfieri; T. Kimoto

doi:10.1063/1.4867200

Investigation of minority carrier traps in p-type mc-Si: Effect of firing and laser annealing

Solar Energy Materials and Solar Cells ◽

10.1016/j.solmat.2021.111341 ◽

2021 ◽

Vol 232 ◽

pp. 111341

Author(s):

Saman Jafari ◽

Ziv Hameiri

Keyword(s):

Laser Annealing ◽

Minority Carrier ◽

Carrier Traps ◽

P Type ◽

Si Effect

Download Full-text

Midgap Levels in As-Grown 4H-SiC Epilayers Investigated by DLTS

Materials Science Forum ◽

10.4028/www.scientific.net/msf.483-485.355 ◽

2005 ◽

Vol 483-485 ◽

pp. 355-358 ◽

Cited By ~ 2

Author(s):

Katsunori Danno ◽

Tsunenobu Kimoto ◽

Hiroyuki Matsunami

Keyword(s):

Electric Fields ◽

Electron Emission ◽

Minority Carrier ◽

Deep Level ◽

Deep Trap ◽

Dlts Spectrum ◽

Carrier Traps ◽

P Type ◽

Two Peaks ◽

Dlts Spectra

Midgap levels in 4H-SiC epilayers have been investigated by DLTS. The EH6/7 center (Ec-1.55 eV) is the dominant deep level as observed in DLTS spectra from n-type epilayers. The activation energy of EH6/7 center is unchanged regardless of applied electric fields, indicating that the charge state of EH6/7 center may be neutral after electron emission (acceptor-like). A DLTS spectrum for a p-type epilayer in the temperature range from 90 to 830 K is dominated by two peaks, D center and a deep trap at 1.49 eV from the valence band edge. Minority carrier traps have been also investigated by DLTS using pn diodes. Two minority carrier traps with activation energies of 1.0 eV and 1.43 eV have been detected.

Download Full-text

Investigating Minority-Carrier Traps in p-type Cu(InGa)Se2 Using Deep Level Transient Spectroscopy

MRS Proceedings ◽

10.1557/proc-865-f5.35 ◽

2005 ◽

Vol 865 ◽

Author(s):

Steven W. Johnston ◽

Jehad A. M. AbuShama ◽

Rommel Noufi

Keyword(s):

Deep Level Transient Spectroscopy ◽

Minority Carrier ◽

Deep Level ◽

Thermionic Emission ◽

Small Peak ◽

Carrier Traps ◽

Transient Spectroscopy ◽

Lower Temperature ◽

And Shifts ◽

P Type

AbstractMeasurements of p-type Cu(InGa)Se2 (CIGS) using deep-level transient spectroscopy (DLTS) show peaks associated with minority-carrier traps, even though data were collected using reverse bias conditions not favorable to injecting minority-carrier electrons. These DLTS peaks occur in the temperature range of 50 to 150 K for the rate windows used and correspond to electron traps having activation energies usually in the range of 0.1 to 0.2 eV for alloys of CIS, CGS, and CIGS. The peak values also depend on the number of traps filled. For short filling times of 10 μs to 100 μs, a small peak appears. As the DLTS filling pulse width increases, the peak increases in response to more traps being filled, but it also broadens and shifts to lower temperature suggesting that a possible series of trap levels, perhaps forming a defect band, are present. The peaks usually saturate in a timeframe of seconds. These filling times are sufficient for electrons to fill traps near the interface from the n-type side of the device due to a thermionic emission current. Admittance spectroscopy data for the same samples are shown for comparison.

Download Full-text

Oxidation-induced majority and minority carrier traps in n- and p-type 4H-SiC

Applied Physics Express ◽

10.7567/apex.8.111301 ◽

2015 ◽

Vol 8 (11) ◽

pp. 111301 ◽

Cited By ~ 4

Author(s):

Takafumi Okuda ◽

Giovanni Alfieri ◽

Tsunenobu Kimoto ◽

Jun Suda

Keyword(s):

Minority Carrier ◽

Carrier Traps ◽

P Type

Download Full-text

A Lifetime Study of Oxygen Agglomeration Induced Defects in Cz Silicon Crystal by Surface Photovoltage (SPV)

MRS Proceedings ◽

10.1557/proc-262-677 ◽

1992 ◽

Vol 262 ◽

Author(s):

Kamal Mishra ◽

W. Huber ◽

Jacek Lagowski

Keyword(s):

Minority Carrier ◽

Diffusion Length ◽

Silicon Crystal ◽

Thermal Treatments ◽

Excitation Light ◽

Order Of Magnitude ◽

Carrier Traps ◽

Effect Of Oxygen ◽

P Type ◽

Induced Defects

ABSTRACTIn this study the effect of oxygen agglomeration on minority carrier diffusion length in as-grown p-CZ silicon has been studied in detail. Oxygen-related defects were found acting as minority carrier traps in p-CZ silicon. These defects are not found in either oxygen-free FZ silicon or in n-type CZ silicon samples. The traps have profound effect on low excitation level diffusion length values leading to an apparent lifetime decrease by as much as an order of magnitude. This effect can be eliminated by a steady state “bias light” superimposed on the chopped excitation light. The traps can be annihilated and re-generated by thermal treatments.Our study has also revealed oxygen-induced recombination centers. Significant improvement in lifetime is realized in p-type CZ silicon after heat treatment between 550°C and 800°C.

Download Full-text

Characterization of a Dominant Electron Trap in GaNAs Using Deep-Level Transient Spectroscopy

MRS Proceedings ◽

10.1557/proc-0891-ee10-35 ◽

2005 ◽

Vol 891 ◽

Author(s):

Steven W. Johnston ◽

Sarah R. Kurtz ◽

Richard S. Crandall

Keyword(s):

Deep Level Transient Spectroscopy ◽

Minority Carrier ◽

Deep Level ◽

Chemical Vapor ◽

Electron Trap ◽

Organic Chemical ◽

Conduction Band Offset ◽

Carrier Traps ◽

Transient Spectroscopy ◽

P Type

ABSTRACTDilute-nitrogen GaNAs epitaxial layers grown by metal-organic chemical vapor deposition were characterized by deep-level transient spectroscopy (DLTS). For all samples, the dominant DLTS signal corresponds to an electron trap having an activation energy of about 0.25 to 0.35 eV. The minority-carrier trap density in the p-type material is quantified based on computer simulation of the devices. The simulations show that only about 2% of the traps in the depleted layer are filled during the transient. The fraction of the traps that are filled depends strongly on the depth of the trap, but only weakly on the doping of the layers and on the conduction-band offset. The simulations provide a pathway to obtain semi-quantitative data for analysis of minority-carrier traps by DLTS.

Download Full-text

Minority carrier traps in Czochralski-grown p-type silicon crystals doped with B, Al, Ga, or In impurity atoms

2020 47th IEEE Photovoltaic Specialists Conference (PVSC) ◽

10.1109/pvsc45281.2020.9300860 ◽

2020 ◽

Author(s):

Joyce Ann T. De Guzman ◽

Vladimir P. Markevich ◽

Simon Hammersley ◽

Ian D. Hawkins ◽

Iain Crowe ◽

...

Keyword(s):

Minority Carrier ◽

Impurity Atoms ◽

Type Silicon ◽

Silicon Crystals ◽

Carrier Traps ◽

P Type

Download Full-text

Deep-Levels Associated with Implanted Titanium in Silicon

MRS Proceedings ◽

10.1557/proc-71-197 ◽

1986 ◽

Vol 71 ◽

Cited By ~ 3

Author(s):

Craig M. Ransom ◽

S.S. Iyer

Keyword(s):

Minority Carrier ◽

Schottky Diodes ◽

Deep Levels ◽

Type Silicon ◽

Carrier Traps ◽

Four Levels ◽

P Type ◽

Ion Implanted

AbstractTitanium was ion implanted at 180 KeV into p-type silicon to form a buried TiSi2 layer. DLTS measurements of n+p junctions have shown two minority carrier traps at Ec − Et = 0.24 and 0.51 eV. Also, a single majority trap at Ev + Et = 0.41 eV was observed. The concentrations of these levels were calculated to be approximately 1013 cm−3. DLTS measurements of low-fluence 50 KeV Ti implantations using Schottky diodes showed four levels dependent on silcon type.

Download Full-text

Minority Carrier Transient Spectroscopy of As-Grown, Electron Irradiated and Thermally Oxidized p-Type 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.778-780.269 ◽

2014 ◽

Vol 778-780 ◽

pp. 269-272 ◽

Cited By ~ 4

Author(s):

Giovanni Alfieri ◽

Tsunenobu Kimoto

Keyword(s):

Energy Range ◽

Minority Carrier ◽

Dose Dependence ◽

Valence Band Edge ◽

Majority Carrier ◽

Irradiation Energy ◽

Carrier Traps ◽

Carrier Trap ◽

Transient Spectroscopy ◽

P Type

A total of nine electrically active levels have been detected in as-grown and electron irradiated p-type 4H-SiC epilayers. These traps are found in the 0.32-2.26 eV energy range, above the valence band edge (EV). Of these, six are majority carrier traps whereas three are minority carrier traps. We found that thermal oxidation affects the concentrations of two midgap levels, the majority carrier trap, labeled HK4 and the minority carrier trap identified as EH6/7. The analysis of the irradiation energy and dose dependence of the concentration of these two traps, rules out the possibility that they may share the same origin.

Download Full-text

Light Effects on Grain Boundary Properties in Silicon

MRS Proceedings ◽

10.1557/proc-5-105 ◽

1981 ◽

Vol 5 ◽

Author(s):

L. J. Cheng ◽

C. M. Shyu

Keyword(s):

Experimental Data ◽

Grain Boundary ◽

Minority Carrier ◽

State Density ◽

Boundary State ◽

Carrier Recombination ◽

Boundary Properties ◽

Light Effects ◽

Recombination Velocity ◽

P Type

ABSTRACTWe have studied the photoconductivity of grain boundaries in p–type silicon. The result demonstrates the applicability of the technique for the measurement of minority carrier recombination velocity at the grain boundary. The experimental data are consistent with the thought that the recombination velocity increases with the boundary state density and light intensity.

Download Full-text