Capacitance and Current Deep-Level Transient Fourier Spectroscopy (DLTFS) for the Characterization of Defect States in Mg-Doped GaN-on-Si p+n Diodes

Gallium nitride (GaN), grown by HVPE, was implanted with 300 keV Eu ions and then annealed at 1000 oC . Deep level transient spectroscopy (DLTS) and Laplace DLTS (L-DLTS) were used to characterise the ion implantation induced defects in GaN. Two of the implantation induced defects, E1 and E2, with DLTS peaks in the 100 – 200 K temperature range, had DLTS signals that could be studied with L-DLTS. We show that these two defects, with energy levels of 0.18 eV and 0.27 eV below the conduction band, respectively, are two configurations of a metastable defect. These two defect states can be reproducibly removed and re-introduced by changing the pulse, bias and temperature conditions, and the transformation processes follow first order kinetics.

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Electrophysical Properties of GaAs P–I–N Structures for Concentrator Solar Cell Applications

Journal of Electrical Engineering ◽

10.1515/jee-2016-0054 ◽

2016 ◽

Vol 67 (5) ◽

pp. 377-382 ◽

Cited By ~ 2

Author(s):

Arpád Kósa ◽

Miroslav Mikolášek ◽

Ľubica Stuchlíková ◽

Ladislav Harmatha ◽

Wojciech Dawidowski ◽

...

Keyword(s):

Solar Cell ◽

Dark Current ◽

Open Circuit Voltage ◽

Deep Level ◽

Open Circuit ◽

Electrophysical Properties ◽

Fourier Spectroscopy ◽

Defect States ◽

Current Voltage ◽

Sun Light

AbstractThis paper is dedicated to electro-physical characterisation of a GaAs p-i-n structure grown for solar cell applications, which was carried out by light and dark current-voltage (I–V) and Deep Level Transient Fourier Spectroscopy (DLTFS) methods. The conversion efficiency and open-circuit voltage were determined fromI–Vmeasurement at 1 and 20× sun light concentrations. Three electron like defects TAn1, TAn2, TDnand one hole like defect TBp obtained by DLTFS measurements were confirmed. The origin of these defect states was stated as native GaAs impurities.

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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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Correlation between Defects and Electrical Performances of Ion-Irradiated 4H-SiC p–n Junctions

Materials ◽

10.3390/ma14081966 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1966

Author(s):

Domenico Pellegrino ◽

Lucia Calcagno ◽

Massimo Zimbone ◽

Salvatore Di Franco ◽

Antonella Sciuto

Keyword(s):

Deep Level ◽

Electrical Characterization ◽

High Fluence ◽

Defect States ◽

Exponential Parameter ◽

Current Voltage ◽

Different Temperatures ◽

In Series ◽

Transient Spectroscopy ◽

Fluence Range

In this study, 4H-SiC p–n junctions were irradiated with 700 keV He+ ions in the fluence range 1.0 × 1012 to 1.0 × 1015 ions/cm2. The effects of irradiation were investigated by current–voltage (I–V) and capacitance–voltage (C–V) measurements, while deep-level transient spectroscopy (DLTS) was used to study the traps introduced by irradiation defects. Modifications of the device’s electrical performances were observed after irradiation, and two fluence regimes were identified. In the low fluence range (≤1013 ions/cm2), I–V characteristics evidenced an increase in series resistance, which can be associated with the decrease in the dopant concentration, as also denoted by C–V measurements. In addition, the pre-exponential parameter of junction generation current increased with fluence due to the increase in point defect concentration. The main produced defect states were the Z1/2, RD1/2, and EH6/7 centers, whose concentrations increased with fluence. At high fluence (>1013 ions/cm2), I–V curves showed a strong decrease in the generation current, while DLTS evidenced a rearrangement of defects. The detailed electrical characterization of the p–n junction performed at different temperatures highlights the existence of conduction paths with peculiar electrical properties introduced by high fluence irradiation. The results suggest the formation of localized highly resistive regions (realized by agglomeration of point defects) in parallel with the main junction.

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Elaboration and Characterization of Mg-Doped ZnO Thin Films by Thermal Evaporation: Annealing Temperature Effect

Brazilian Journal of Physics ◽

10.1007/s13538-021-00866-y ◽

2021 ◽

Author(s):

Fouaz Lekoui ◽

Salim Hassani ◽

Mohammed Ouchabane ◽

Hocine Akkari ◽

Driss Dergham ◽

...

Keyword(s):

Thin Films ◽

Temperature Effect ◽

Annealing Temperature ◽

Thermal Evaporation ◽

Zno Thin Films ◽

Doped Zno ◽

Mg Doped

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Growth of GaN without Yellow Luminescence

MRS Proceedings ◽

10.1557/proc-395-625 ◽

1995 ◽

Vol 395 ◽

Cited By ~ 23

Author(s):

X. Zhang ◽

P. Kung ◽

D. Walker ◽

A. Saxler ◽

M. Razeghi

Keyword(s):

Vapor Deposition ◽

Metalorganic Chemical Vapor Deposition ◽

Deep Level ◽

Chemical Vapor ◽

Growth Conditions ◽

Native Defect ◽

Yellow Luminescence ◽

Gallium Vacancy ◽

Rich Condition

ABSTRACTWe report the growth and photoluminescence characterization of GaN grown on different substrates and under different growth conditions using metalorganic chemical vapor deposition. The deep-level yellow luminescence centered at around 2.2eV is attributed to native defect, most possibly the gallium vacancy. The yellow luminescence can be substantially reduced By growing GaN under Ga-rich condition or doping GaN with Ge or Mg.

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