共查询到20条相似文献,搜索用时 15 毫秒
1.
L. V. Krasil’nikova M. V. Stepikhova Yu. N. Drozdov M. N. Drozdov Z. F. Krasil’nik V. G. Shengurov V. Yu. Chalkov S. P. Svetlov O. B. Gusev 《Physics of the Solid State》2005,47(1):93-97
Si/Si1?xGex: Er/Si structures grown by sublimation molecular-beam epitaxy (SMBE) in a gas phase are studied. These structures are considered possible structures for realizing a Si/Er-based laser. It is shown that SMBE in a gas phase can be applied to create effective light-emitting structures that generate an intense luminescence signal at a wavelength of 1.54 μm. The structures and chemical compositions of the Si/Si1?xGx: Er/Si structures, whose parameters are close to those calculated for creating laser-type structures, are examined, and their photoluminescence (PL) spectra and kinetics are studied at 4.2 and 77 K. It is shown that the fraction of Er3+ optically active centers in the Si1?xGx: Er layers thus grown reaches ~10% of the total erbium-impurity concentration. The optical gains in the active Si1?xGx: Er layers at x = 0.1 and 0.02 are estimated to be ~0.03 and ~0.2 cm?1, respectively. The gain in structures of this type can be significantly increased via the intentional formation of isolated Er3+ optically active centers whose PL spectra have a characteristic fine structure. 相似文献
2.
N. A. Sobolev D. V. Denisov A. M. Emel’yanov E. I. Shek B. Ya. Ber A. P. Kovarskii V. I. Sakharov I. T. Serenkov V. M. Ustinov G. E. Cirlin T. V. Kotereva 《Physics of the Solid State》2005,47(1):113-116
The technology and properties of light-emitting structures based on silicon layers doped by erbium during epitaxial MBE growth are studied. The epitaxial layer forming on substrates prepared from Czochralski-grown silicon becomes doped by oxygen and carbon impurities in the process. This permits simplification of the Si: Er layer doping by luminescence-activating impurities, thus eliminating the need to make a special capillary for introducing them into the growth chamber from the vapor phase. The photoluminescence spectra of all the structures studied at 78 K are dominated by an Er-containing center whose emission line peaks at 1.542 μm. The intensity of this line measured as a function of the substrate and erbium dopant source temperatures over the ranges 400–700°C and 740–800°C, respectively, exhibits maxima. The edge luminescence and the P line observed in the PL spectra are excited predominantly in the substrate. The erbium atom concentration in the epitaxial layers grown at a substrate temperature of 600°C was studied by Rutherford proton backscattering and exhibits an exponential dependence on the erbium source temperature with an activation energy of ~2.2 eV. 相似文献
3.
V. B. Shmagin D. Yu. Remizov Z. F. Krasil’nik V. P. Kuznetsov V. N. Shabanov L. V. Krasil’nikova D. I. Kryzhkov M. N. Drozdov 《Physics of the Solid State》2004,46(1):109-112
A series of Si: Er/Si light-emitting diode structures with a smoothly varying p-n junction breakdown mechanism, grown through sublimation molecular-beam epitaxy, is used to investigate the effect of the breakdown mechanism on the electroluminescence of the structures. The maximal intensity and excitation efficiency of room-temperature Er3+ ion electroluminescence are shown to be attained in diode structures with a mixed breakdown mechanism. 相似文献
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S. Coffa S. Lombardo F. Priolo G. Franzó S. U. Campisano A. Polman G. N. van den Hoven 《Il Nuovo Cimento D》1996,18(10):1131-1148
Summary In this work we demonstrate that efficient light emission at 1.54 μm can be achieved when Er ions are incorporated into crystalline
Si or in heavily oxygen-doped amorphous and polycrystalline Si films (SIPOS). We have found that temperature quenching of
photo- and electroluminescence, which is the major limitation towards the achievement of room temperature luminescence, can
be strongly reduced by codoping these films with oxygen. This impurity is already present in as-prepared SIPOS and it is introduced
by ion-implantation in crystalline Si. Er luminescence is obtained under both optical and electrical excitation and we demonstrate
that excitation occurs through a carrier-mediated process. Electrical excitation is obtained by incorporating Er in properly
designed device structures. It is found that this excitation can occur both through the recombination of hole-electron pairs
and through impact excitation of the Er ions by hot electrons. These two mechanisms have different efficiencies and impact
excitation is shown to prevail at room temperature. These data are presented and possible future developments are discussed.
Paper presented at the III INSEL (Incontro Nazionale sul Silicio Emettitore di Luce), Torino, 12–13 October 1995. 相似文献
6.
Maria Eloisa Castagna Salvatore Coffa Mariantonietta Monaco Liliana Caristia Alberto Messina Rosario Mangano Corrado Bongiorno 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):547
We report on the fabrication and performances of extremely efficient Si-based light sources. The devices consist of MOS structures with erbium (Er) implanted in the thin gate oxide. The devices exhibit strong 1.54 μm electroluminescence (EL) at 300 K with a 10% external quantum efficiency, comparable to that of standard light-emitting diodes using III–V semiconductors. Er excitation is caused by hot electrons impact and oxide wearout limits the reliability of the devices. Much more stable light-emitting MOS devices have been fabricated using Er-doped silicon rich oxide (SRO) films as gate dielectric. These devices show a high stability, with an external quantum efficiency reduced to 1%. In these devices, Er pumping occurs by energy transfer from the Si nanostructures to the rare-earth ions. Finally, we have also fabricated MOS structures with Tb- and Yb-doped SiO2 which show room temperature EL at 540 nm (Tb) and 980 nm (Yb) with an external quantum efficiency of a 10% and 0.1%, respectively. 相似文献
7.
The Si solar cells were irradiated with high energy hydrogen ions of 10, 30, 60 and 120?keV at the dose rate of 1017 H+ ions (proton)/cm2. The structural, optical and electrical properties of the implanted samples and fabricated cells were studied. The implantation induced defects bringing structural changes before and after annealing was evidenced by the transmission electron microscopy. The Raman spectrum showed a change of crystalline to amorphous state at 480?cm?1 when the sample was implanted by hydrogen ion of 30?keV energy. Formation of nanocrystallite layers were observed after annealing. The electroluminescence images showed that hydrogen-related defect centers were involved in the emission mechanism. The photoluminescence emission from the implanted cells was attributed to nanocrystallite layers. From current–voltage measurements, the conversion efficiencies of implanted Si solar cells were found lower than the un-implanted reference cell. The ion implantation did not passivate the defects rather acted as recombination centers. 相似文献
8.
D. Pacifici A. Irrera G. Franz M. Miritello F. Iacona F. Priolo 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):331
In the last decade, a strong effort has been devoted towards the achievement of efficient light emission from silicon. Among the different approaches, rare-earth doping and quantum confinement in Si nanostructures have shown great potentialities. In the present work, the synthesis and properties of low-dimensional silicon structures in SiO2 will be analyzed. All of these structures present a strong room temperature optical emission, tunable in the visible by changing the crystal size. Moreover, Si nanocrystals (nc) embedded in SiO2 together with Er ions show a strong coupling with the rare earth. Indeed each Si nc absorbs energy which is then preferentially transferred to the nearby Er ions. The signature of this interaction is the strong increase of the excitation cross section for an Er ion in the presence of Si nc with respect to a pure oxide host. We will show the properties of Er-doped Si nc embedded within Si/SiO2 Fabry–Pérot microcavities. Very narrow, intense and highly directional luminescence peaks can be obtained. Moreover, the electroluminescence (EL) properties of Si nc and Er-doped Si nc in MOS devices are investigated. It is shown that an efficient carrier injection at low voltages and quite intense room temperature EL signals can be achieved, due to the sensitizing action of Si nc for the rare earth. These data will be presented and the impact on future applications discussed. 相似文献
9.
S. Prucnal J.M. Sun A. Nazarov I.P. Tjagulskii I.N. Osiyuk R. Fedaruk W. Skorupa 《Applied physics. B, Lasers and optics》2007,88(2):241-244
When amorphous silica is bombarded with energetic ions, various types of defects are created as a consequence of ion-solid
interaction (oxygen deficient centers (ODC), non-bridging oxygen hole centers (NBOHC), E′-centers, etc.). Luminescent peaks from oxygen deficiency centers at 2.7 eV, non-bridging oxygen hole centers at 1.9 eV and
defect centers with emission at 2.07 eV were observed by changing the concentration of implanted Gd3+ ions. Charge trapping in Gd-implanted SiO2 layers was induced using constant current electron injection to study the electroluminescence intensity with dependence on
the applied voltage change. The process of electron trap generation during high field carrier injection results in an increase
of the electroluminescence from non-bridging oxygen hole centers. Direct correlation between electron trapping and the quenching
of the electroluminescence at 2.07 eV and 2.7 eV was observed with variation of the implanted Gd concentration.
PACS 78.60.i; 72.20.Jv; 78.20.-e 相似文献
10.
利用射频磁控溅射方法,在n+-Si衬底上淀积SiO2/Si/SiO2 sub>纳米双势垒单势阱结构,其中Si层厚度为2至4nm,间隔为0.2nm,邻近n+-S i衬底的SiO2层厚度固定为1.5nm,另一SiO2层厚度固定为3nm.为了 对比研究,还制备了Si层厚度为零的结构,即SiO2(4.5nm)/n+-Si 结构.在经过600℃氮气下退火30min,正面蒸上半透明Au膜,背面也蒸Au作欧姆接触后,所 有样品都在反向偏置(n+-Si的电压高于Au电极的电压)下发光,而在正向偏压 下不发光.在一定的反向偏置下,电流和电致发光强度都随Si层厚度的增加而同步振荡,位 相相同.所有样品的电致发光谱都可分解为相对高度不等的中心位于2.26eV(550nm)和1.85eV (670nm)两个高斯型发光峰.分析指出该结构电致发光的机制是:反向偏压下的强电场使Au/( SiO2/Si/SiO2)纳米双势垒/n+-Si结构发生了雪崩击穿 ,产生大量的电子-空穴对,它们在纳米SiO2层中的发光中心(缺陷或杂质)上复 合而发光.
关键词:
电致发光
纳米双势垒
高斯型发光峰
雪崩击穿 相似文献
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S. Iwan S. Bambang J.L. Zhao S.T. Tan H.M. Fan L. Sun S. Zhang H.H. Ryu X.W. Sun 《Physica B: Condensed Matter》2012,407(14):2721-2724
Erbium-doped ZnO (ZnO:Er) thin films with various doping concentrations were deposited on p-Si substrates by ultrasonic spray pyrolysis (USP). The n-ZnO:Er/p-Si heterojunctions were further employed to fabricate light-emitting diodes (LEDs). The devices showed diode-like rectifying current–voltage characteristics with a low reverse breakdown voltage, attributed to the avalanche breakdown. A distinct green electroluminescence peaking at 537 nm and 558 nm were observed at room temperature under reverse bias. The green electroluminescence originated from the electron impact excitation of Er3+ ions doped in ZnO films. 相似文献
13.
P. G. Baranov I. V. Ilyin E. N. Mokhov A. B. Pevtsov V. A. Khramtsov 《Physics of the Solid State》1999,41(1):32-34
Erbium ions have been incorporated for the first time in bulk 6H-SiC crystals during growth, and they were unambiguously identified from the 167Er EPR hyperfine structure. High-temperature luminescence of erbium ions at a wavelength of 1.54 μm has been detected. The observed luminescence exhibits an increase in intensity with increasing temperature. The observation
of Er luminescence in 6H-SiC offers a promising potential for development of semiconductor light-emitting devices at a wavelength within the fiber-optics
transparency window.
Fiz. Tverd. Tela (St. Petersburg) 41, 38–40 (January 1999) 相似文献
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T. Gebel L. Rebohle J. Sun W. Skorupa 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):366
In this paper we explore the electroluminescence (EL) properties of thermally grown 350 nm thick SiO2 layers co-implanted with Si+ and C+ ions. The implanted fluences were chosen in such a way that peak concentrations of excess Si and C of 5–10 at% were achieved. The devices show a broad photoluminescence (PL) between 2.0 and 3.2 eV with a main peak around 2.7 eV. The broad EL spectra show additional peaks around 3.3 eV and between 2.1 and 2.5 eV which are decreased with increasing Si/C concentration. The shape of the EL spectra does not change with increasing injection currents which implies that various types of defects occur for the different concentrations. The device stability is improved in comparison to Ge or Sn implanted oxide layers. 相似文献
16.
D. Yu. Remizov V. B. Shmagin A. V. Antonov V. P. Kuznetsov Z. F. Krasil’nik 《Physics of the Solid State》2005,47(1):98-101
A series of Si: Er electroluminescent diode structures is fabricated by sublimation molecular-beam epitaxy. The diode structures efficiently emit at a wavelength of 1.5 μm under conditions of p-n junction breakdown at room temperature. The effective cross section of excitation of Er3+ ions with hot carriers heated by the electric field of a reverse-biased p-n junction and the lifetime of Er3+ ions in the first excited state 4I13/2 are determined for structures that emit in a mixed breakdown mode and are characterized by the maximum intensity and excitation efficiency of the Er3+ electroluminescence. 相似文献
17.
B. A. Andreev Z. F. Krasil’nik V. P. Kuznetsov A. O. Soldatkin M. S. Bresler O. B. Gusev I. N. Yassievich 《Physics of the Solid State》2001,43(6):1012-1017
The photoluminescence of semiconducting structures Si: Er: O/Si grown by the molecular-beam epitaxy method is studied. The dependences of Er photoluminescence intensity on the intensity of pumping are measured at the liquid helium temperature. An analysis of the experimental results on the basis of the exciton model of excitation of Er ions in a crystalline silicon matrix reveals the significant role played by an alternative channel of free-exciton trapping (apart from the donor energy levels of erbium-oxygen complexes), as well as that played by the nonradiative channel in the recombination of excitons, bound to erbium donors, without the excitation of erbium. The ratio of the concentration of optically active centers of erbium luminescence to the total concentration of introduced erbium is estimated. 相似文献
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Jun Xu Guran Chen Chao Song Kunji Chen Xinfan Huang Zhongyuan Ma 《Applied Surface Science》2010,256(18):5691-1293
Laser induced crystallization of ultrathin hydrogenated amorphous Si films or amorphous Si-based multilayered structures were used to get high density Si nanodots. The present technique can get size controllable Si nanodots embedded in various dielectric materials with uniform distribution which was revealed by cross-section transmission electron microscopy. Room temperature photoluminescence and electroluminescence were achieved with the emission wavelength in a visible light region both from a-SiN/Si nanodots/a-SiN sandwiched and Si nanodots/SiO2 multilayered structures. The luminescence was associated with the radiative recombination of generated electron-hole pairs in Si nanodots or the luminescent surface states. The electroluminescence intensity is increased with increasing the injection current implying the bipolar carrier injection plays an important role in enhancing the luminescence efficiency. The formed Si nanodots by the present approach can be applied for many kinds of devices such as high efficient light emitting diodes and solar cells. 相似文献