Radiative recombination processes of thermal donors in silicon

AbstractThere is a recent, renewed attention on the possible development of optical emitters compatible with silicon microelectronic technology and it has been recently shown that light emitting diodes could be manufactured on dislocated silicon, where dislocations were generated by plastic deformation or ion implantation. Among other potential sources of room temperature light emission, compatible with standard silicon-based ULSI technology, we have studied old thermal donors (OTD), as the origin of their luminescence is still matter of controversy and demands further investigation.In this work we discuss the results of a spectroscopical study of OTD using photoluminescence (PL) and Deep Level Transient Spectroscopy (DLTS) on standard Czochralsky (Cz) silicon samples and on carbon-doped samples.We were able to show that their main optical activity, which consists of a narrow band at 0.767 eV ( P line), is correlated to a transition from a shallow donor level of OTD to a deep level at EV+0.37 eV which is tentatively associated to C-O complexes. As we have shown that the P line emission persists at room temperature, we discuss about its potentialities to silicon in optoelectronic applications.

Download Full-text

Role of deep levels in DC current aging of GaN/InGaN Light-Emitting Diodes studied by Capacitance and Photocurrent Spectroscopy

MRS Proceedings ◽

10.1557/proc-0892-ff12-11 ◽

2005 ◽

Vol 892 ◽

Cited By ~ 1

Author(s):

Antonio Castaldini ◽

Anna Cavallini ◽

Lorenzo Rigutti ◽

Matteo Meneghini ◽

Simone Levada ◽

...

Keyword(s):

Quantum Wells ◽

Light Emission ◽

Deep Level ◽

Bulk Material ◽

Deep Levels ◽

Light Emitting ◽

Photocurrent Spectroscopy ◽

Charge Concentration ◽

Transient Spectroscopy ◽

Dc Current

AbstractWe present a combined Capacitance-Voltage (C-V), Deep Level Transient Spectroscopy (DLTS) and Photocurrent (PC) study of short-term instabilities of InGaN/GaN LEDs submitted to forward current aging tests at room temperature. C-V profiles detect changes consisting in apparent doping and/or charge concentration increase within the quantum wells. This increase is correlated to dramatic modifications in the DLTS spectrum when the reverse bias and filling pulse are properly adjusted in order to probe the quantum well region. The new distribution of the electronic levels detected by DLTS could explain the observed decrease in the light emission efficiency [1,2] of the device, as the deep levels generated during the stress may provide alternative recombination paths for free carriers. The photocurrent spectra do not change in shape during stress, although their amplitude slightly decreases. This is related to a decrease of the device yield, in this photodetector configuration, with increasing aging time. Thus, we can suggest that the introduction of new defect levels in the bulk material lowers the free carrier mobility.

Download Full-text

Rare Earth Ion Implantation for Silicon Based Light Emission

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.108-109.755 ◽

2005 ◽

Vol 108-109 ◽

pp. 755-760 ◽

Cited By ~ 7

Author(s):

Wolfgang Skorupa ◽

J.M. Sun ◽

S. Prucnal ◽

L. Rebohle ◽

T. Gebel ◽

...

Keyword(s):

Rare Earth ◽

Ion Implantation ◽

Indium Tin Oxide ◽

Light Emission ◽

Charge Trapping ◽

Electrical Performance ◽

Rare Earth Ion ◽

Light Emitting ◽

Silicon Based ◽

Luminescent Centers

Using ion implantation different rare earth luminescent centers (Gd3+, Tb3+, Eu3+, Ce3+, Tm3+, Er3+) were formed in the silicon dioxide layer of a purpose-designed Metal Oxide Silicon (MOS) capacitor with advanced electrical performance, further called a MOS-light emitting device (MOSLED). Efficient electroluminescence was obtained for the wavelength range from UV to infrared with a transparent top electrode made of indium-tin oxide. Top values of the efficiency of 0.3 % corresponding to external quantum efficiencies distinctly above the percent range were reached. The electrical properties of these devices such as current-voltage and charge trapping characteristics, were also evaluated. Finally, application aspects to the field of biosensing will be shown.

Download Full-text

Traps in Si-doped AlxGa1-xN Grown by Molecular Beam Epitaxy on Sapphire Characterized by Deep Level Transient Spectroscopy

MRS Proceedings ◽

10.1557/proc-0955-i15-30 ◽

2006 ◽

Vol 955 ◽

Author(s):

Mo Ahoujja ◽

S Elhamri ◽

M Hogsed ◽

Y. K. Yeo ◽

R. L. Hengehold

Keyword(s):

Molecular Beam Epitaxy ◽

Deep Level Transient Spectroscopy ◽

Molecular Beam ◽

Deep Level ◽

Unknown Origin ◽

Shallow Donor ◽

Related Point ◽

Line Defects ◽

Si Doped ◽

Transient Spectroscopy

ABSTRACTDeep levels in Si doped AlxGa1−xN samples, with Al mole fraction in the range of x = 0 to 0.30, grown by radio-frequency plasma activated molecular beam epitaxy on sapphire substrates were characterized by deep level transient spectroscopy (DLTS). DLTS measurements show two significant electron traps, P1 and P2, in AlGaN at all aluminum mole fractions. The electron trap, P2, appears to be a superposition of traps A and B , both of which are observed in GaN grown by various growth techniques and are thought to be related to VGa-shallow donor complexes. Trap P1 is related to line defects and N-related point defects. Both of these traps are distributed throughout the bulk of the epitaxial layer. An additional trap P0 which was observed in Al0.20Ga0.80N and Al0.30Ga0.70N is of unknown origin, but like P1 and P2, it exhibits dislocation-related capture kinetics. The activation energy measured from the conduction band of the defects is found to increase with Al mole content, a behavior consistent with other III-V semiconductors.

Download Full-text

Влияние нейтронного облучения на спектр дефектов с глубокими уровнями в GaAs, изготовленном методом жидкофазной эпитаксии в атмосфере водорода и аргона

Физика и техника полупроводников ◽

10.21883/ftp.2022.01.51812.9729 ◽

2022 ◽

Vol 56 (1) ◽

pp. 53

Author(s):

М.М. Соболев ◽

Ф.Ю. Солдатенков

Keyword(s):

Deep Level Transient Spectroscopy ◽

Deep Level ◽

Experimental Studies ◽

Shallow Donor ◽

Defect Clusters ◽

Deep Traps ◽

Capacitance Voltage ◽

Before And After ◽

Transient Spectroscopy ◽

Different Doses

The results of experimental studies of capacitance– voltage characteristics, spectra of deep-level transient spectroscopy of graded high-voltage GaAs p+−p0−i−n0 diodes fabricated by liquid-phase epitaxy at a crystallization temperature of 900C from one solution–melt due to autodoping with background impurities, in a hydrogen or argon ambient, before and after irradiation with neutrons. After neutron irradiation, deep-level transient spectroscopy spectra revealed wide zones of defect clusters with acceptor-like negatively charged traps in the n0-layer, which arise as a result of electron emission from states located above the middle of the band gap. It was found that the differences in capacitance–voltage characteristics of the structures grown in hydrogen or argon ambient after irradiation are due to different doses of irradiation of GaAs p+−p0−i−n0 structures and different degrees of compensation of shallow donor impurities by deep traps in the layers.

Download Full-text

Light Emission from Intrinsic and Doped Silicon-Rich Silicon Oxide: from the Visible to 1.6 ΜM

MRS Proceedings ◽

10.1557/proc-452-523 ◽

1996 ◽

Vol 452 ◽

Cited By ~ 2

Author(s):

L. Tsybeskov ◽

K. L. Moore ◽

P. M. Fauchet ◽

D. G. Hall

Keyword(s):

Rare Earth ◽

External Quantum Efficiency ◽

Room Temperature ◽

Structural Modification ◽

Silicon Oxide ◽

Light Emission ◽

Crystalline Silicon ◽

Light Emitting ◽

Infra Red ◽

Doped Silicon

AbstractSilicon-rich silicon oxide (SRSO) films were prepared by thermal oxidation (700°C-950°C) of electrochemically etched crystalline silicon (c-Si). The annealing-oxidation conditions are responsible for the chemical and structural modification of SRSO as well as for the intrinsic light-emission in the visible and near infra-red spectral regions (2.0–1.8 eV, 1.6 eV and 1.1 eV). The extrinsic photoluminescence (PL) is produced by doping (via electroplating or ion implantation) with rare-earth (R-E) ions (Nd at 1.06 μm, Er at 1.5 μm) and chalcogens (S at ∼1.6 μm). The impurities can be localized within the Si grains (S), in the SiO matrix (Nd, Er) or at the Si-SiO interface (Er). The Er-related PL in SRSO was studied in detail: the maximum PL external quantum efficiency (EQE) of 0.01–0.1% was found in samples annealed at 900°C in diluted oxygen (∼ 10% in N2). The integrated PL temperature dependence is weak from 12K to 300K. Light emitting diodes (LEDs) with an active layer made of an intrinsic and doped SRSO are manufactured and studied: room temperature electroluminescence (EL) from the visible to 1.6 μmhas been demonstrated.

Download Full-text

Light Emitting Diode with MOS Structures Containing Multiple-Stacked Si Quantum Dots

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.557 ◽

2007 ◽

Vol 121-123 ◽

pp. 557-560 ◽

Cited By ~ 5

Author(s):

J. Xu ◽

Katsunori Makihara ◽

Hidenori Deki ◽

Yoshihiro Kawaguchi ◽

Hideki Murakami ◽

...

Keyword(s):

Quantum Dots ◽

Luminescence Intensity ◽

Room Temperature ◽

Light Emission ◽

Light Emitting Diode ◽

Infrared Light ◽

Gate Bias ◽

Light Emitting ◽

Mos Structures ◽

Si Quantum Dots

Light emitting diode with MOS structures containing multiple-stacked Si quantum dots (QDs)/SiO2 was fabricated and the visible-infrared light emission was observed a room temperature when the negative gate bias exceeded the threshold voltage. The luminescence intensity was increased linearly with increasing the injected current density. The possible luminescence mechanism was briefly discussed and the delta P doping was performed to obtain the doped Si QDs and the improvement of EL intensity was demonstrated.

Download Full-text

Study of the Radiative and Non-Radiative Recombination Processes at Dislocations in Silicon by Photoluminescence and LBIC Measurements

MRS Proceedings ◽

10.1557/proc-588-117 ◽

1999 ◽

Vol 588 ◽

Cited By ~ 6

Author(s):

S. Pizzini ◽

S. Binetti ◽

M. Acciarri ◽

M. Casati

Keyword(s):

Radiative Recombination ◽

Room Temperature ◽

Light Emission ◽

Energy Levels ◽

The Third ◽

Optical Telecommunications ◽

Recombination Processes ◽

Metallic Impurities ◽

Room Temperature Luminescence ◽

Dislocation Related Luminescence

AbstractIt is well known that the sharp, room temperature luminescence emission at 1.54 μm from dislocated silicon has set off a great interest for this material in view of its applications in the third window of optical telecommunications. For this reason the dislocation related luminescence in silicon addressed recently a number of investigation aimed at understanding the mechanism of light emission. The problem is still unsolved as most of the experiments done gave contradictory answers to the main questions open, which concern the intrinsic or extrinsic nature of dislocation luminescence and the effect on it of reconstruction, interaction or passivation processes, possibly assisted by metallic or non-metallic impurities.In order to go more insight on the problem, we started a systematic work on CZ silicon, aimed at understanding the properties of dislocation luminescence. The identification of the energy levels involved in the different dislocation PL bands has been obtained.

Download Full-text

The Effect of Impurity Content and Ion Mass on the Depth Profiles of Vacancy-Type Defects in MeV Implanted Si

MRS Proceedings ◽

10.1557/proc-438-65 ◽

1996 ◽

Vol 438 ◽

Cited By ~ 4

Author(s):

S. Libertino ◽

S. Coffa ◽

V. Privitera ◽

F. Priolo

Keyword(s):

Room Temperature ◽

Depth Distribution ◽

Deep Level ◽

Impurity Content ◽

Initial Distribution ◽

Monte Carlo Code ◽

Depth Profiles ◽

Defect Complexes ◽

Range Migration ◽

Transient Spectroscopy

AbstractWe used deep level transient spectroscopy to determine the concentration and depth profile of the defects introduced by MeV He and Si implants in n-type crystalline Si. We have found that only ∼ 16% of the Frenkel pairs generated by the ion escapes recombination and is stored into room temperature stable defects such as divacancies and oxygen vacancy complexes. For a light ion (He), the depth distribution of these defect complexes is strongly dependent on the O content of the substrate: it mirrors the initial distribution of I-V pairs, as calculated by TRIM (a Monte Carlo Code) when the O content is high (∼ 1018/cm3) while it can be much wider (up to 2 μm) in a highly pure (low O content) epitaxial substrate. This effect is due to a long range migration of vacancies before clustering or trapping at impurities. This migration is strongly inhibited for an ion of higher mass (such as Si) since in a denser collision cascade direct clustering is strongly favoured with respect to agglomeration of migrating defects.

Download Full-text

Shallow and Deep Level Defects in GaN

MRS Proceedings ◽

10.1557/proc-395-443 ◽

1995 ◽

Vol 395 ◽

Cited By ~ 30

Author(s):

W. Götz ◽

N.M. Johnson ◽

D.P. Bour ◽

C. Chen ◽

H. Liu ◽

...

Keyword(s):

Deep Level ◽

Variable Temperature ◽

Shallow Donor ◽

Deep Levels ◽

Electron Photoemission ◽

Hall Effect Measurements ◽

Transient Spectroscopy ◽

P Type ◽

Capacitance Transient ◽

Threshold Energies

ABSTRACTShallow and deep electronic defects in MOCVD-grown GaN were characterized by variable temperature Hall effect measurements, deep level transient spectroscopy (DLTS) and photoemission capacitance transient spectroscopy (O-DLTS). Unintentionally and Si-doped, n-type and Mg-doped, p-type GaN films were studied. Si introduces a shallow donor level into the band gap of GaN at ∼Ec - 0.02 eV and was found to be the dominant donor impurity in our unintentionally doped material. Mg is the shallowest acceptor in GaN identified to date with an electronic level at ∼Ev + 0.2 eV. With DLTS deep levels were detected in n-type and p-type GaN and with O-DLTS we demonstrate several deep levels with optical threshold energies for electron photoemission in the range between 0.87 and 1.59 eV in n-type GaN.

Download Full-text