Phase Formation Between Codeposited Co-Ta Thin Film and Single Crystal Silicon Substrate

AbstractA combination of near-noble and refractory metal silicides was considered for shallow contacts to silicon in VLSI circuits [1]. The objective of the present work is to investigate formation of phases between codeposited Co-Ta film, of 150 nm thickness, and n-type silicon substrates of (100) or (111) orientation. Characterization of the specimens annealed in the temperature range of 600–1100°C was done by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that in addition to the silicide phases of Co and Ta, the intermetallic compound Co2 Ta was also formed. Co2 Ta appears only in the lower temperature range of about 600–800°C. At temperatures of 900–1100°C only the silicon rich phases were present. These are the low resistivity phases useful for devices. No ternary phases have been observed. Silicide formation occurs at a faster rate on (111) oriented silicon substrates.

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TEM characterization of Au/Polysilicon interactions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176381 ◽

1990 ◽

Vol 48 (4) ◽

pp. 650-651

Author(s):

N. David Theodore ◽

Leslie H. Allen ◽

C. Barry Carter ◽

James W. Mayer

Keyword(s):

Solid Phase ◽

Single Crystal Silicon ◽

Chemical Vapor ◽

Electrical Contacts ◽

Silicon Substrates ◽

Crystal Silicon ◽

Transmission Electron ◽

Polysilicon Films ◽

The Stability

Metal/polysilicon investigations contribute to an understanding of issues relevant to the stability of electrical contacts in semiconductor devices. These investigations also contribute to an understanding of Si lateral solid-phase epitactic growth. Metals such as Au, Al and Ag form eutectics with Si. reactions in these metal/polysilicon systems lead to the formation of large-grain silicon. Of these systems, the Al/polysilicon system has been most extensively studied. In this study, the behavior upon thermal annealing of Au/polysilicon bilayers is investigated using cross-section transmission electron microscopy (XTEM). The unique feature of this system is that silicon grain-growth occurs at particularly low temperatures ∽300°C).Gold/polysilicon bilayers were fabricated on thermally oxidized single-crystal silicon substrates. Lowpressure chemical vapor deposition (LPCVD) at 620°C was used to obtain 100 to 400 nm polysilicon films. The surface of the polysilicon was cleaned with a buffered hydrofluoric acid solution. Gold was then thermally evaporated onto the samples.

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Synthesis and Selected Micro-Mechanical Properties of Titanium Nitride Thin Films by the Pyrolysis of Tetrakis Titanium in Ammonia.

MRS Proceedings ◽

10.1557/proc-363-245 ◽

1994 ◽

Vol 363 ◽

Cited By ~ 1

Author(s):

Y. W. Bae ◽

W. Y. Lee ◽

T. M. Besmann ◽

P. J. Blau ◽

L. Riester

Keyword(s):

Thin Films ◽

Titanium Nitride ◽

Electron Spectroscopy ◽

Single Crystal Silicon ◽

Chemical Vapor ◽

Silicon Substrates ◽

X Ray Diffraction ◽

Crystal Silicon ◽

Transmission Electron ◽

Chemical Vapor Deposited

AbstractThin films of titanium nitride were chemical vapor deposited on (100)-oriented single-crystal silicon substrates from tetrakis (dimethylamino) titanium, Ti((CH3)2N)4, and ammonia gas mixtures in a cold-wall reactor at 623 K and 655 Pa. The films were characterized by Auger electron spectroscopy, X-ray diffraction, and transmission electron spectroscopy. The nano-scale hardness of the film, measured by nanoindentation, was 12.7±0.6 GPa. The average kinetic friction coefficient against unlubricated, type- 440C stainless steel was determined using a computer-controlled friction microprobe to be ∼0.43.

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Microwave Activation of Dopants & Solid Phase Epitaxy in Silicon

MRS Proceedings ◽

10.1557/proc-0989-a06-18 ◽

2007 ◽

Vol 989 ◽

Cited By ~ 4

Author(s):

Douglas C. Thompson ◽

J. Decker ◽

T. L. Alford ◽

J. W. Mayer ◽

N. David Theodore

Keyword(s):

Single Crystal ◽

Microwave Heating ◽

Rutherford Backscattering Spectrometry ◽

Solid Phase ◽

Single Crystal Silicon ◽

Silicon Substrates ◽

Crystal Silicon ◽

Cross Sectional ◽

Transmission Electron ◽

Microwave System

AbstractMicrowave heating is used to activate solid phase epitaxial re-growth of amorphous silicon layers on single crystal silicon substrates. Layers of single crystal silicon were made amorphous through ion implantation with varying doses of boron or arsenic. Microwave processing occurred inside a 2.45 GHz, 1300 W cavity applicator microwave system for time-durations of 1-120 minutes. Sample temperatures were monitored using optical pyrometery. Rutherford backscattering spectrometry, and cross-sectional transmission electron microscopy were used to monitor crystalline quality in as-implanted and annealed samples. Sheet resistance readings show dopant activation occurring in both boron and arsenic implanted samples. In samples with large doses of arsenic, the defects resulting from vacancies and/or micro cluster precipitates are seen in transmission electron micrographs. Materials properties are used to explain microwave heating of silicon and demonstrate that the damage created in the implantation process serves to enhance microwave absorption.

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Effect of Boron Doping on the C49 TO C54 Phase Transformation in Ti/Si (100) Bilayers

MRS Proceedings ◽

10.1557/proc-441-303 ◽

1996 ◽

Vol 441 ◽

Author(s):

M. Libera ◽

A. Quintero

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Single Crystal ◽

Single Crystal Silicon ◽

Interface Roughness ◽

Ex Situ ◽

Silicon Substrates ◽

Crystal Silicon ◽

Boron Doped ◽

Transmission Electron

AbstractWe have demonstrated that the formation of C54 TiSi2 on Boron-doped single crystal silicon substrates, under RTA annealing conditions in a Nitrogen ambient, leads to a thicker TiN capping surface layer, thinner silicide layer, higher C49 to C54 transformation temperature and greater interface roughness compared to C54 TiSi 2 formation on undoped single crystal silicon substrates. Titanium films 32 nm thick were deposited on undoped and boron-doped single crystal silicon substrates. The films were annealed at 3 /C/isn nitrogen to final quenching temperatures between 500 °C and 900 TC. Ex-situ four point probe sheet resistance, cross sectional transmission electron microscopy (XTEM), high resolution transmission electron microscopy (HRTEM) and x-ray diffraction (XRD) were used to analyze the resulting TiN on TiSi2 bilayer. The C49 to C54 transformation occurs circa 760 TC and 810 TC for the undoped and boron-doped cases respectively. HRTEM observations reveal a thick 20 nm TIN layer on the C54 TiSi2 film in the boron-doped case but only fine dispersed TiN particles embedded on the top of the silicide in the undoped case. It was observed that the resultant silicide in the boron-doped case was thinner and the TiSi2 /Si(100) interface is rougher. XRD and TEM analysis show that in the boron doped case, there is a preferred C54 (040) orientation compared to a random orientation for the undoped case.

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An Epitaxial Si/insulator/Si Structure Prepared by Vacuum Deposition of CaF2 and Silicon

MRS Proceedings ◽

10.1557/proc-10-145 ◽

1981 ◽

Vol 10 ◽

Author(s):

T. Asano ◽

H. Ishiwara

Keyword(s):

Substrate Temperature ◽

Silicon Film ◽

Single Crystal Silicon ◽

Rutherford Backscattering ◽

Film Deposition ◽

Silicon Substrates ◽

Optimum Conditions ◽

Crystal Silicon ◽

Transmission Electron ◽

Substrate Temperatures

Heteroepitaxial CaF2/Si and Si/CaF2/Si structures were prepared by conventional vacuum evaporation of CaF2 and silicon onto silicon substrates. The optimum conditions for obtaining good epitaxial films were investigated by changing the silicon substrate orientation, the film thickness and the substrate temperature during film deposition. From Rutherford backscattering and channelling spectroscopy it was found that CaF2 films with excellent film quality were obtained on Si(111), Si(110) and Si(100) substrates at substrate temperatures of 600– 800°C, 800°C and 500–600°C respectively. It was also found from Rutherford backscattering and channelling spectroscopy and from transmission electron microscopy that single-crystal silicon films are formed on a CaF2/Si(111) structure at a substrate temperature of 700°C. From measurements of the electrical properties of the top silicon film after the implantation of phosphorus ions at 2 ×1015 cm−2 and subsequent annealing at 750°C, an electron Hall mobility of 69cm2 V−1 s−1 was obtained.

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Electrostatic Aerosol Deposition Method for the Formation of an Ensemble of Monodisperse Particles on a Substrate

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.41.53 ◽

2016 ◽

Vol 41 ◽

pp. 53-62

Author(s):

Alexey A. Efimov ◽

Anna A. Lizunova ◽

Elena G. Kalinina ◽

Valentin S. Sukharev ◽

Victor V. Ivanov

Keyword(s):

Particle Density ◽

Single Crystal Silicon ◽

Aerosol Deposition ◽

Crystal Silicon ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Aerosol Deposition Method ◽

Single Crystal Silicon Substrate ◽

Microscopy Data

We have developed an aerosol-based technique for deposition of monodisperse ensembles of spherical SiO2 nanoparticles on the surface of single-crystal silicon substrate (1 cm2) with an average surface particle density of about 2.1±0.4 particles per μm2. The obtained samples of monodisperse ensembles SiO2 nanoparticles was characterized by scanning and transmission electron microscopy. The ensemble of deposited nanoparticles is characterized by a narrow size distribution with a modal size of 26.6 nm and a full width at half maximum of 3.5 nm according to the atomic force microscopy data. We have demonstrated the use of the obtained test structure to determine the effective radius of the tip of an atomic force microscope.

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Far-infrared properties of helium-doped silicon

Canadian Journal of Physics ◽

10.1139/cjp-2014-0403 ◽

2015 ◽

Vol 93 (8) ◽

pp. 935-940

Author(s):

Wei Ren ◽

Qingyan Zhou ◽

Bing Li ◽

Hongxiang Deng ◽

Shaobo Han ◽

...

Keyword(s):

Refractive Index ◽

Absorption Coefficient ◽

Single Crystal Silicon ◽

Far Infrared ◽

Wave Number ◽

Crystal Silicon ◽

Number Range ◽

Temperature Range ◽

Transmission Electron ◽

Wave Number Range

Single crystal silicon is an important material used for semiconductor devices and also a potential material in device research. Far-infrared optical properties are studied for the helium ion implanted samples with different fluences of 5.0 × 1016, 1.0 × 1017, 2.0 × 1017, and 4.0 × 1017 cm−2. The absorption coefficient and refractive index of silicon with different helium concentrations are measured in the wave number range from 4 to 85 cm−1 and temperature range from 145 to 520 K. The results show that the absorption coefficient increases with increasing fluence of helium ions, but the refractive index decreases. The correlations between absorption coefficient and refractive index and temperature of all samples are similar. The refractive index increases with temperature in the whole measurement temperature range, but the absorption coefficient has different trends in the different wavebands. The absorption coefficient decreases with the increase of temperature in the region below 12 cm−1; however, the absorption coefficient increases when the wave number is larger than 30 cm−1. The absorption coefficient curves at different wavebands are well fitted by the Drude model. A large number of helium bubbles and defects, such as voids and dislocations have been observed in the implanted area by transmission electron microscopy (TEM), which contributes to the increase of optical absorption.

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Electron Microscope Observations of Mechanisms of thin Film Delamination from Substrates

MRS Proceedings ◽

10.1557/proc-119-291 ◽

1988 ◽

Vol 119 ◽

Cited By ~ 1

Author(s):

D. Goyal ◽

A. H. King

Keyword(s):

Thin Film ◽

Electron Microscope ◽

Film Formation ◽

Single Crystal Silicon ◽

Metal Films ◽

Model Systems ◽

Silicon Substrates ◽

Formation Model ◽

Crystal Silicon ◽

Transmission Electron

AbstractTransmission electron microscope techniques have been applied to the problem of thin film delamination from substrates during film formation. Model systems involving metal films on single crystal silicon substrates have been used and it is found that delamination of the films is initiated by the formation of damage in the substrate. This understanding removes some of the fundamental problems regarding delamination.

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A Current Conduction Mechanism in Laser Recrystallized Silicon Metal-Oxide-Semiconductor Transistors

MRS Proceedings ◽

10.1557/proc-23-603 ◽

1983 ◽

Vol 23 ◽

Author(s):

Han-Sheng Lee

Keyword(s):

Conduction Mechanism ◽

Single Crystal Silicon ◽

Silicon Films ◽

Oxide Semiconductor ◽

Silicon Substrates ◽

Mos Transistors ◽

Crystal Silicon ◽

Ion Laser ◽

Argon Ion ◽

A Current

ABSTRACTN-channel MOS transistors were fabricated on silicon films that had been recrystallized by an argon ion laser at different power levels. These transistors showed electrical characteristics similar, but somewhat inferior to those devices fabricated on single crystal silicon substrates. These differences are attributed to the presence of trapping states at the grain boundaries of the crystallites in the recrystallized silicon. A coulombic scattering model is presented to explain these differences. In the case of films annealed at low laser power, an additional factor of nonuniform trap state distribution is invoked to explain device characteristics. This model provides an adequate explanation for the observed transport properties of transistors fabricated from recrystallized silicon films.

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