Sputtered WSix for micromechanical structures

Tungsten silicide (WSix) thin tilms have been investigated for use as integrated circuit interconnect and self-aligned MESFET (metal-semiconductor field-effect transistor) gates because of their low resistivity and thermal and chemical stability. These same characteristics make them interesting materials for prospective use in micromechanical structures. However, little information on residual stresses, elastic moduli, or other micromechanical properties has been available for refractory metal silicide thin films. This paper presents the morphology and stress characteristics of cosputtered WSix thin films, including crystal structure variations and orientation-dependent stresses, as a function of the deposition pressure. The compositions of WSix thin films were analyzed by Rutherford backscattering spectrometry (RBS). The biaxial elastic modulus and thermal coefficient of expansion were found for the sputtered films. Stress-measurement methods and annealing are discussed. Released diaphragms of different sizes and shapes, having controlled residual stress, have been fabricated.

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Characterization of Sputtered Tungsten Silicide as a Micromechanical Material

MRS Proceedings ◽

10.1557/proc-276-283 ◽

1992 ◽

Vol 276 ◽

Cited By ~ 1

Author(s):

Muh-Ling Ger ◽

Richard B. Brown

Keyword(s):

Integrated Circuit ◽

Refractory Metal ◽

Stress Measurement ◽

Thermal Coefficient ◽

Tungsten Silicide ◽

Sputtered Films ◽

Deposition Parameters ◽

Metal Silicides ◽

Sputter Deposited

ABSTRACTRefractory metal silicides, such as tungsten silicide (WSix), have been used for integrated circuit interconnect and self-aligned MESFET gates because of their low resistivity and thermal and chemical stability. These same characteristics make refractory metal silicides interesting materials for prospective use in micromechanical structures. However, little information on residual stresses, elastic moduli, or other micromechanical properties has been available for refractory metal silicide films.This paper presents morphology and stress characteristics of sputter-deposited tungsten silicide films, including orientation-dependent variations, as functions of deposition parameters. The biaxial elastic modulus and thermal coefficient of expansion are found for our sputtered films. Stress-measurement methods and annealing are discussed. Released diaphragms of different sizes and shapes, having controlled residual stress, have been fabricated.

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Influence of the Microstructure on the Optical Characteristics of SrTiO3 thin films

Journal of Materials Research ◽

10.1557/jmr.2005.0002 ◽

2005 ◽

Vol 20 (1) ◽

pp. 68-74 ◽

Cited By ~ 8

Author(s):

M. Gaidi ◽

L. Stafford ◽

A. Amassian ◽

M. Chaker ◽

J. Margot ◽

...

Keyword(s):

Thin Films ◽

Refractive Index ◽

Photoelectron Spectroscopy ◽

Secondary Ion Mass Spectrometry ◽

Rutherford Backscattering Spectrometry ◽

Optical Characteristics ◽

Silicon Substrates ◽

Deposition Pressure ◽

X Ray ◽

Full Characterization

The influence of the microstructure of strontium-titanate-oxide (SrTiO3 or STO) thin films on their optical properties was investigated through an extensive characterization. The STO films have been deposited on silicon substrates by reactive pulsed laser deposition. The effect of the oxygen deposition pressure on the crystalline quality of the films was systematically studied by x-ray diffraction and scanning electron microscopy. Rutherford backscattering spectrometry, x-ray photoelectron spectroscopy, and secondary ion mass spectrometry were used to determine the atomic density and depth concentration profiles of the various species forming the film. The refractive index and extinction coefficient were obtained using variable angle spectroscopic ellipsometry. Based on this full characterization, it is demonstrated that the optical characteristics of the films are directly correlated to their microstructural properties. In particular, the refractive index increases with film density, while losses decrease. In addition, the interface between STO and Si is characterized by an interdiffusion layer. As the deposition pressure is enhanced, the width of this layer significantly increases, inducing localized inhomogeneity of the refractive index.

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The Precipitation of Si in AlCuSi Thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070618 ◽

1973 ◽

Vol 31 ◽

pp. 34-35 ◽

Cited By ~ 1

Author(s):

R. M. Anderson

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Heat Treatment ◽

Solid Solution ◽

Integrated Circuit ◽

Copper Film ◽

Solution Concentration ◽

X Ray ◽

Silicon Thin Films ◽

Before And After

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.

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Preparation of TEM samples by focused ion beams

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138968 ◽

1995 ◽

Vol 53 ◽

pp. 518-519

Author(s):

John F. Walker ◽

J C Reiner ◽

C Solenthaler

Keyword(s):

Integrated Circuit ◽

Polycrystalline Silicon ◽

Field Effect Transistor ◽

High Spatial Resolution ◽

Ion Beam ◽

Ion Beams ◽

Focused Ion Beams ◽

Precise Location ◽

Effect Transistor ◽

Circuit Technology

The high spatial resolution available from TEM can be used with great advantage in the field of microelectronics to identify problems associated with the continually shrinking geometries of integrated circuit technology. In many cases the location of the problem can be the most problematic element of sample preparation. Focused ion beams (FIB) have previously been used to prepare TEM specimens, but not including using the ion beam imaging capabilities to locate a buried feature of interest. Here we describe how a defect has been located using the ability of a FIB to both mill a section and to search for a defect whose precise location is unknown. The defect is known from electrical leakage measurements to be a break in the gate oxide of a field effect transistor. The gate is a square of polycrystalline silicon, approximately 1μm×1μm, on a silicon dioxide barrier which is about 17nm thick. The break in the oxide can occur anywhere within that square and is expected to be less than 100nm in diameter.

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Preferential Orientation of Photochromic Gadolinium Oxyhydrides

10.26434/chemrxiv.12377690.v1 ◽

2020 ◽

Author(s):

Elbruz Murat Baba ◽

Jose Montero ◽

Dmitrii Moldarev ◽

Marcos V. Moro ◽

Max Wolff ◽

...

Keyword(s):

Thin Films ◽

Grain Size ◽

Rare Earth ◽

Preferential Orientation ◽

Reactive Magnetron ◽

Flow Ratio ◽

Deposition Pressure ◽

Step Process ◽

Oxidation In Air ◽

Key Parameter

We report preferential orientation control in photochromic gadolinium oxyhydride (GdHO) thin films deposited by a two-step process. Gadolinium hydride (GdH2-x) films were grown by reactive magnetron sputtering, followed by oxidation in air. The preferential orientation, grain size, anion concentrations, and photochromic response of the films are strongly dependent on the deposition pressure. GdHO films show preferential orientation along the [100] direction and exhibit photochromism when synthesized at deposition pressures up to 5.8 Pa and. The photochromic contrast is larger than 20 % when the films are deposited below 2.8 Pa with 0.22 H2/Ar flow ratio. We argue that the degree of preferential orientation defines the oxygen concentration which is known to be a key parameter for photochromism in rare-earth oxyhydride thin films. The experimental observations described above are explained by the oxidation-induced decrease of the grain size as a result of the increase of the deposition pressure of the sputtering gas.

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Modelling of Dynamic Properties of Silicon Carbide Junction Field-Effect Transistors (JFETs)

Energies ◽

10.3390/en13010187 ◽

2020 ◽

Vol 13 (1) ◽

pp. 187 ◽

Cited By ~ 1

Author(s):

Kamil Bargieł ◽

Damian Bisewski ◽

Janusz Zarębski

Keyword(s):

Silicon Carbide ◽

Integrated Circuit ◽

Field Effect ◽

Field Effect Transistors ◽

Dynamic Properties ◽

Modified Model ◽

Spice Model ◽

Capacitance Voltage ◽

Effect Transistor ◽

Switching Characteristics

The paper deals with the problem of modelling and analyzing the dynamic properties of a Junction Field Effect Transistor (JFET) made of silicon carbide. An examination of the usefulness of the built-in JFET Simulation Program with Integrated Circuit Emphasis (SPICE) model was performed. A modified model of silicon carbide JFET was proposed to increase modelling accuracy. An evaluation of the accuracy of the modified model was performed by comparison of the measured and calculated capacitance–voltage characteristics as well as the switching characteristics of JFETs.

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Deposition pressure-induced microstructure control and plasmonic property tuning in hybrid ZnO-AgxAu1-x thin films

Nanoscale Advances ◽

10.1039/d0na00887g ◽

2021 ◽

Author(s):

Robynne Lynne PALDI ◽

Xing Sun ◽

Xin Li Phuah ◽

Juanjuan Lu ◽

Xinghang Zhang ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Laser Deposition ◽

Deposition Method ◽

Hybrid Films ◽

Deposition Pressure ◽

Plasmonic Metamaterials ◽

Film Form

Self-assembled oxide-metallic alloyed nanopillars as hybrid plasmonic metamaterials (e.g., ZnO-AgxAu1-x) in a thin film form are grown using a pulsed laser deposition method. The hybrid films were demonstrated to be...

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Indentation Technique to Investigate Elastic Moduli of Thin Films on Substrates

MRS Proceedings ◽

10.1557/proc-130-105 ◽

1988 ◽

Vol 130 ◽

Cited By ~ 1

Author(s):

D. S. Stone ◽

T. W. Wu ◽

P.-S. Alexopoulos ◽

W. R. Lafontaine

Keyword(s):

Thin Film ◽

Experimental Data ◽

Thin Films ◽

Closed Form ◽

Elastic Moduli ◽

Depth Sensing ◽

Indentation Technique ◽

Average Displacement ◽

Elasticity Solutions ◽

Poor Adhesion

AbstractClosed-form elasticity solutions are introduced, that predict the average displacement beneath square and triangular, uniformly loaded areas at the surface of a bilayer. The solutions aid in the application of depth-sensing indentation techniques for measuring thin film elastic moduli. The elasticity solutions agree closely with experimental data of Al, Si, 1 μm Al on Si, and 2 μm Cr on Si. The case of poor adhesion between the film and substrate is briefly examined.

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