Visible Light Emission in Silicon-Interface Adsorbed Gas Superlattices

ABSTRACTHaving an indirect fundamental bandgap, unlike III-V or II-VI compound semiconductors, silicon has not played a role in optoelectronic applications such as injection lasers and light emitting diodes. In an attempt to introduce a sufficient quantum size effect, we present the experimental results on a new type of silicon based superlattices consisting of alternating layers of silicon and monolayers of adsorbed gases, Si/IAG multilayers (Si/Interface Adsorbed Gas), constructed by repeated interruptions of silicon deposition with adsorbed gases of oxygen and hydrogen. Fairly strong visible luminescence has been observed.

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Surface and optical properties of porous silicon

Journal of Materials Research ◽

10.1557/jmr.1996.0036 ◽

1996 ◽

Vol 11 (2) ◽

pp. 305-320 ◽

Cited By ~ 59

Author(s):

S. M. Prokes

Keyword(s):

Porous Silicon ◽

Light Emission ◽

Semiconductor Industry ◽

Radiative Transition ◽

Emission Process ◽

Carrier Recombination ◽

Quantum Size ◽

Visible Luminescence ◽

Weak Light ◽

Silicon Based

Although silicon is the material of choice in the semiconductor industry, it has one serious disadvantage: it is an extremely poor optoelectronic material. This is because it is an indirect gap semiconductor, in which radiative transition results in extremely weak light emission in the infrared part of the spectrum. Thus, the discovery of strong visible luminescence from a silicon-based material (porous silicon) has been quite surprising and has generated significant interest, both scientific and technological. This material differs from bulk silicon in one important way, in that it consists of interconnected silicon nanostructures with very large surface to volume ratios. Although the first mechanism proposed to explain this emission process involved carrier recombination within quantum size silicon particles, more recent work has shown that the surface chemistry appears to be the controlling factor in this light emission process. Thus, the aim of this work is to outline the data and arguments that have been presented to support the quantum confinement model, along with the shortcomings of such a model, and to examine more recent models in which the chemical and structural properties of the surface regions of the nanostructures have been incorporated.

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TEM analysis of light emitting porous silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131620 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1398-1399

Author(s):

M. W. Cole ◽

J. F. Harvey ◽

R.A. Lux ◽

D.W. Eckart

Keyword(s):

Porous Silicon ◽

Integrated Circuits ◽

Light Emission ◽

Tem Analysis ◽

Cross Sectional ◽

Light Emitting ◽

Visible Luminescence ◽

Transmission Electron ◽

Potential Applications ◽

Silicon Based

The recent observations of visible light emission from porous silicon layers (PSL) have attracted much interest due to its potential applications in silicon based optoelectronic integrated circuits, optical memories and advanced display systems. To realize these potential applications this material must be fully characterized. Specifically, the microstructure must be studied in order to understand the origin of the light emission. Unfortunately, the issue of the detailed geometry of porous silicon is not fully resolved because of the difficulty in performing transmission electron microscopy (TEM) measurements on these fragile structures. One of the first microstructural studies on visible emitting PSL, presented by Cullis and Canham, showed the material to be composed of needle-like structures having a cross sectional diameter of 3nm. It was suggested that the visible luminescence in this material is due to quantum confinement of these small structures. A major limitation of this work was the method of TEM sample preparation.

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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.

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Optical Properties of Microcrystalline Silicon in Oxide Matrix through Partial Oxidation of Anodized Porous Silicon

MRS Proceedings ◽

10.1557/proc-256-127 ◽

1991 ◽

Vol 256 ◽

Cited By ~ 9

Author(s):

Toshimichi Ito ◽

Toshimichi Ohta ◽

Osamu Arakaki ◽

Akio Hiraki

Keyword(s):

Optical Properties ◽

Porous Silicon ◽

Partial Oxidation ◽

Silicon Oxide ◽

Light Emission ◽

Wavelength Region ◽

Microcrystalline Silicon ◽

Quantum Size ◽

Visible Luminescence ◽

Oxide Matrix

ABSTRACTMicrocrystalline silicon embedded in silicon oxide has been prepared by means of partial oxidation of porous silicon produced anodically from degenerate p-Si wafers. Their optical properties such as absorption coefficients and luminescence have been characterized. Results show blue shifts in absorption and photoluminescence spectra in a visible wavelength region with decreasing size of the microcrystalline Si in the Si oxide matrix. The quantum size effect is discussed as well as possible origins of the observed visible luminescence, including light emission from as-anodized (or H-chemisorbed) porous silicon.

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Radiative recombination processes of thermal donors in silicon

MRS Proceedings ◽

10.1557/proc-692-h6.30.1 ◽

2001 ◽

Vol 692 ◽

Cited By ~ 5

Author(s):

S. Pizzini ◽

S. Binetti ◽

E. Leoni ◽

A. Le Donne ◽

M. Acciarri ◽

...

Keyword(s):

Room Temperature ◽

Light Emission ◽

Deep Level ◽

Line Emission ◽

Shallow Donor ◽

Light Emitting ◽

Microelectronic Technology ◽

Recombination Processes ◽

Transient Spectroscopy ◽

Silicon Based

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.

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A Novel Silicon-Based Packaging Platform for High-Efficiency LED Modules

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.314-316.359 ◽

2011 ◽

Vol 314-316 ◽

pp. 359-363

Author(s):

Cong Wang ◽

Won Sang Lee ◽

Nam Young Kim

Keyword(s):

Heat Dissipation ◽

High Efficiency ◽

Light Emitting Diode ◽

Chemical Vapor ◽

Anodized Aluminum ◽

Anodized Aluminum Oxide ◽

Insulating Layer ◽

Light Emitting ◽

New Type ◽

Silicon Based

A novel silicon-based packaging platform with the electroplated-based reflector and the electrode- guided interconnections is developed for the packaging component of a high-luminosity and high-efficiency multi-chip light-emitting diode (LED) module, which is patterned on a new type of insulating layer that consists of nanoporous anodized aluminum oxide (AAO) layer and plasma- enhanced chemical vapor deposition (PECVD) deposited silicon dioxide (SiO2) on a doped silicon substrate. The reflector and the electrical interconnections are successfully fabricated by using the electroplating method in the same body. In order to obtain the benefits of high efficiency LED modules, the requirements concerning thermal management and photomechanical layout have to be met. In this paper, we will discuss a novel fabrication method in LED module packaging platform, and then describe the thin layer of electroplated Cu/Ni/Au in order to reduce thermal resistance and to increase thermal diffusion efficiency. The heat generated by the LED chips is dissipated directly to the silicon body through the metal-plated platform, and truly excellent heat dissipation characteristics are observed. We demonstrate 987 lm 8 W-level cool-white light (5000 K, 16 V, 110 lm/W, CRI = 77) emission for 570 µm × 230 µm-chip LEDs at 600 mA operation.

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Microstructure and enhanced photoluminescence of ZnO/V2O5 composite

International Journal of Modern Physics B ◽

10.1142/s0217979217440519 ◽

2017 ◽

Vol 31 (16-19) ◽

pp. 1744051

Author(s):

Xinghua Zhan ◽

Fei Chen ◽

Zoran Salcic ◽

Chee Cheong Wong ◽

Wei Gao

Keyword(s):

Zinc Oxide ◽

Optical Properties ◽

High Efficiency ◽

Light Emission ◽

Coupling Effect ◽

Light Emitting ◽

Vertical Deposition ◽

Enhanced Photoluminescence ◽

Zno Particles ◽

New Type

Submicron zinc oxide (ZnO) spheres prepared by a two-stage hydrothermal method were assembled into a layer on a substrate by vertical deposition. Vanadium pentoxide (V2O5) was deposited onto the top of ZnO spheres by magnetron sputtering followed by annealing in oxygen atmosphere at 500[Formula: see text]C for an hour. The microstructures and optical properties of the prepared samples were investigated. The photoluminescence (PL) results indicate that the intensity of PL in the annealed ZnO/V2O5 composite microstructures is dramatically improved compared to the constituent V2O5 and ZnO spheres. The intensity enhancement of light emission from the ZnO/V2O5 composite may be attributed to the special microstructure of ZnO particles and the coupling effect between ZnO and V2O5. This transition oxide composite may possibly be developed into a new type of high-efficiency light emitting material.

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Blue Light Emission from Porous Silicon

MRS Proceedings ◽

10.1557/proc-283-89 ◽

1992 ◽

Vol 283 ◽

Cited By ~ 2

Author(s):

X. Y. Hou ◽

G. Shi ◽

W. Wang ◽

F. L. Zhang ◽

P. H. Hao ◽

...

Keyword(s):

Porous Silicon ◽

Blue Light ◽

Light Emission ◽

Green Light ◽

Blue Shift ◽

Blue Light Emission ◽

Light Emitting ◽

Visible Luminescence ◽

Infrared Reflection ◽

Green Light Emission

ABSTRACTThrough a post treatment of light emitting porous silicon in boilingwater, a large blue shift of its photoluminescence (PL) spectrum hasbeen observed and a stable blue-green light emission at the peak wavelength down to 500 nm is achieved. The effect of boiling water treatment is suggested to be a kind of oxidation, which could reduce thesize of the Si column, fill up some micropores and strengthen the Siskeleton. The photoluminescence microscopic observation shows that the surface of blue light emitting porous silicon is composed of manysmall uniformly light-emitting domains at the size of several tens of μm. Fourier transform infrared reflection (FTIR) measurements show that the formation of Si-H bonds is not responsible for the visible luminescence in the very thin Si wires.

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