On the recombination centers of iron-gallium pairs in Ga-doped silicon

AbstractProspects of laser operation in erbium doped silicon has been analyzed by a Shockley-Read-Hall (SRH) model. Erbium atoms have been considered to be introducing strong recombination centers in the silicon lattice. Electron-hole recombination at these sites were considered to be the source of erbium excitation. A two level system was considered for calculation of optical gain and the laser threshold. For a laser cavity of 300 μm with mirror reflectivities of 90%, and an optimistic absorption coefficient of 5 cm-1, a population inversion of 1.4×1018/cm3 was estimated as the threshold value. Achievement of the lasing condition was found feasible, but only for certain conditions of erbium activation. Effects of nonradiative deexcitation routes have been analyzed. On the assumption of 1019/cm3 of active erbium sites, linear increase of optical power in the laser cavity has been estimated for injected carrier densities above 1018/cm3.

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Er-Doped Porous Silicon Led For Integrated Optoelectronics

MRS Proceedings ◽

10.1557/proc-486-145 ◽

1997 ◽

Vol 486 ◽

Author(s):

L. Tsybeskov ◽

G. F. Grom ◽

K. D. Hirschman ◽

H. A. Lopez ◽

S. Chan ◽

...

Keyword(s):

Porous Silicon ◽

Room Temperature ◽

Silicon Oxide ◽

Light Emitting Diode ◽

Inert Atmosphere ◽

Light Emitting ◽

Doped Silicon ◽

Recombination Centers ◽

Er Doped

AbstractPorous silicon (PSi) was doped by Er using electromigration from a solution and converted to Er-doped silicon-rich silicon oxide (SRSO:Er) by partial thermal oxidation at 600–950°C following densification at 1100°C in an inert atmosphere. Room-temperature photoluminescence (PL) at ∼1.5 μm is intense and decreases by less than 20% from 12 K to 300 K. The PL spectrum of SRSO:Er reveals no luminescence bands related to Si-bandedgerecombination, point defects or dislocations, and shows that the Er3+ centers are the most efficient radiative recombination centers. A light-emitting diode (LED) with an active layer made of SRSO:Er was manufactured using a pre-oxidation cleaning step to increase the quality of the interface between SRSO:Er and the top electrode. Room temperature electroluminescence at ∼1.5 μm was demonstrated.

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High-resolution transmission electron microscopic study of highly oxygen doped silicon layer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155438 ◽

1989 ◽

Vol 47 ◽

pp. 692-693

Author(s):

H. Takaoka ◽

M. Tomita ◽

T. Hayashi

Keyword(s):

High Resolution ◽

Oxygen Concentration ◽

Silicon Layer ◽

Detailed Structure ◽

Electron Microscopic ◽

Cross Sectional ◽

Transmission Electron ◽

Doped Silicon ◽

Argon Ion

High resolution transmission electron microscopy (HRTEM) is the effective technique for characterization of detailed structure of semiconductor materials. Oxygen is one of the important impurities in semiconductors. Detailed structure of highly oxygen doped silicon has not clearly investigated yet. This report describes detailed structure of highly oxygen doped silicon observed by HRTEM. Both samples prepared by Molecular beam epitaxy (MBE) and ion implantation were observed to investigate effects of oxygen concentration and doping methods to the crystal structure.The observed oxygen doped samples were prepared by MBE method in oxygen environment on (111) substrates. Oxygen concentration was about 1021 atoms/cm3. Another sample was silicon of (100) orientation implanted with oxygen ions at an energy of 180 keV. Oxygen concentration of this sample was about 1020 atoms/cm3 Cross-sectional specimens of (011) orientation were prepared by argon ion thinning and were observed by TEM at an accelerating voltage of 400 kV.

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Determination of arsenic atom distribution arsenic doped silicon using HOLZ-line analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167342 ◽

1996 ◽

Vol 54 ◽

pp. 976-977

Author(s):

Y. Kikuchi ◽

N. Hashikawa ◽

F. Uesugi ◽

E. Wakai ◽

K. Watanabe ◽

...

Keyword(s):

Inelastic Scattering ◽

Zone Axis ◽

Experimental Result ◽

Background Intensity ◽

Crystal Thickness ◽

Arsenic Atom ◽

Doped Silicon ◽

P Type ◽

Line Analysis

In order to measure the concentration of arsenic atoms in nanometer regions of arsenic doped silicon, the HOLZ analysis is carried out underthe exact [011] zone axis observation. In previous papers, it is revealed that the position of two bright lines in the outer SOLZ structures on the[011] zone axis is little influenced by the crystal thickness and the background intensity caused by inelastic scattering electrons, but is sensitive to the concentration of As atoms substitutbnal for Siatomic site.As the result, it becomes possible to determine the concentration of electrically activated As atoms in silicon within an observed area by means of the simple fitting between experimental result and dynamical simulatioan. In the present work, in order to investigate the distribution of electrically activated As in silicon, the outer HOLZ analysis is applied using a nanometer sized probe of TEM equipped with a FEG.Czodiralsld-gown<100>orientated p-type Si wafers with a resistivity of 10 Ώ cm are used for the experiments.TheAs+ implantation is performed at a dose of 5.0X1015cm-2at 25keV.

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Preparation of integrated circuits for TEM electromigration in situ studies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145753 ◽

1986 ◽

Vol 44 ◽

pp. 882-883

Author(s):

J. V. Maskowitz ◽

W. E. Rhoden ◽

D. R. Kitchen ◽

R. E. Omlor ◽

P. F. Lloyd

Keyword(s):

Integrated Circuits ◽

Crystallographic Orientation ◽

Silicon Wafers ◽

Minimum Size ◽

Test Vehicle ◽

In Situ Studies ◽

Boron Doped ◽

Doped Silicon ◽

Drill Holes

The fabrication of the aluminum bridge test vehicle for use in the crystallographic studies of electromigration involves several photolithographic processes, some common, while others quite unique. It is most important to start with a clean wafer of known orientation. The wafers used are 7 mil thick boron doped silicon. The diameter of the wafer is 1.5 inches with a resistivity of 10-20 ohm-cm. The crystallographic orientation is (111).Initial attempts were made to both drill and laser holes in the silicon wafers then back fill with photoresist or mounting wax. A diamond tipped dentist burr was used to successfully drill holes in the wafer. This proved unacceptable in that the perimeter of the hole was cracked and chipped. Additionally, the minimum size hole realizable was > 300 μm. The drilled holes could not be arrayed on the wafer to any extent because the wafer would not stand up to the stress of multiple drilling.

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