Fast robust eye-safe large working distance non-contact technology for ex-situ and in-situ stress, topography, wafer thickness, internal layer thickness metrology for semiconductor, MEMS, and precision manufacturing

2021 ◽  
Author(s):  
Wojtek J. Walecki
Keyword(s):  
Layer Thickness ◽  
In Situ Stress ◽  
Internal Layer ◽  
Ex Situ ◽  
Precision Manufacturing ◽  
Wafer Thickness ◽  
Working Distance

In-Situ Stress Measurements During Dry Oxidation of Silicon

1997 ◽  
Vol 473 ◽  
Author(s):  
Chia-Liang Yu ◽  
Paul A. Flinn ◽  
John C. Bravman
Keyword(s):  
Oxide Thickness ◽  
In Situ Stress ◽  
Stress Generation ◽  
Ex Situ ◽  
Strong Function ◽  
One Dimensional ◽  
Dry Oxidation ◽  
In Situ Stress Measurements ◽  
Good Agreement

ABSTRACTIn this study, we present results of both in-situ and ex-situ measurements of stress generated during dry oxidation of silicon. We show that the mechanical stress in as-grown dry oxides is a strong function of oxidation temperature and oxide thickness, but a weak function of oxygen partial pressure. We have identified a structural relaxation phenomenon after the oxide is formed, and found that the viscosity of the oxide increases with its age; consequently, the stress relaxation slows down due to this increase of viscosity. In this paper, we present a one-dimensional mechanical model to simulate the stress generation and relaxation during dry oxidation of silicon. The simulations of both in-situ and ex-situ tests are in good agreement with the experimental measurements.

Phase Transformation and Microstructural Properties in Sputtered Vs. CVD WSi, Films

1996 ◽  
Vol 441 ◽  
Author(s):  
A. Dornenicucci ◽  
C. Dehm ◽  
S. Loh ◽  
L. A. Clevenger ◽  
C. Dziobkowski ◽  
...  
Keyword(s):  
Grain Size ◽  
Phase Transformation ◽  
Tetragonal Phase ◽  
Hexagonal Phase ◽  
Atomic Ratio ◽  
In Situ Stress ◽  
Ex Situ ◽  
Sputtered Films ◽  
Electron Spectrometry

AbstractCVD WSi, films produced by dichlorosilane reduction at 570°C and WSi, films sputter deposited at 50°C were characterized by in situ x-ray diffraction (IS-XRD), in situ resistivity (ISRes), in situ stress (IS-stress), ex situ/in situ transmission electron microscopy (EX/IS-TEM) and ex situ Auger electron spectrometry (EX-AES) over the temperature range 25–1100°C. The CVD films were crystalline after deposition, with columnar grains in the hexagonal phase and a Si:W atomic ratio of 2.6:1. The CVD films exhibited a sharp hexagonal to tetragonal phase transformation near 750°C. The final grain size was greater than the film thickness, with no evidence of voiding. Avrami analyses gave traditional curves with n values of 2 for the phase transition in the CVD films. In comparison, the sputtered films were amorphous as deposited (Si:W atomic ratio of 2.8:1 ) and crystallized to a different hexagonal phase microstructure than did the CVD films. The sputtered films showed a broad hexagonal to tetragonal phase transformation near 800°C, and a final grain size that was less than the fihn thickness with much voiding. A low Avrami exponent of 0.2 to 0.4 was obtained for the transformation of the sputtered films.

Size and critical thickness evolution during growth of stacked layers of InAs/InP(001) quantum wires studied by in situ stress measurements

2003 ◽  
Vol 794 ◽  
Author(s):  
David Fuster ◽  
María Ujué González ◽  
Luisa González ◽  
Yolanda González ◽  
Teresa Ben ◽  
...  
Keyword(s):  
Critical Thickness ◽  
Quantum Wires ◽  
High Energy ◽  
In Situ Stress ◽  
Ex Situ ◽  
Stress Measurements ◽  
Transmission Electron ◽  
In Situ Stress Measurements ◽  
20 Nm

ABSTRACTSize and spatial distribution homogeneity of nanostructures is greatly improved by making stacks of nanostructures separated by thin spacers. In this work we present in situ and in real time stress measurements and reflection high energy electron diffraction (RHEED) observations and ex situ transmission electron microscopy (TEM) characterization of stacked layers of InAs quantum wires (QWr) separated by InP spacer layers, d(InP), of thickness between 3 and 20 nm. For d(InP) < 20 nm, the amount of InAs involved in the newly created QWr from the 2nd stack layer on, exceeds that provided by the In cell. Our results suggest that in those cases InAs 3D islands formation starts at the P/As switching and lasts during further InAs deposition. We propose an explanation for this process that is strongly supported on TEM observations. The results obtained in this work imply that concepts like the existence of a critical thickness for 2D-3D growth mode transition should be revised in correlated QWr stacks of layers.

An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

1988 ◽  
Vol 46 ◽  
pp. 884-885
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Defect Density ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Metal Base ◽  
In Situ Experiments ◽  
Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

The use of transmission and analytical electron microscopy in studying reactions and phase transformations in thin film

1993 ◽  
Vol 51 ◽  
pp. 842-843
Author(s):  
K. Barmak
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Phase Transformations ◽  
Analytical Electron Microscopy ◽  
Ex Situ ◽  
Multilayer Thin Films ◽  
Absolute Concentration ◽  
Analytical Electron ◽  
Deposition Step

Generally, processing of thin films involves several annealing steps in addition to the deposition step. During the annealing steps, diffusion, transformations and reactions take place. In this paper, examples of the use of TEM and AEM for ex situ and in situ studies of reactions and phase transformations in thin films will be presented.The ex situ studies were carried out on Nb/Al multilayer thin films annealed to different stages of reaction. Figure 1 shows a multilayer with dNb = 383 and dAl = 117 nm annealed at 750°C for 4 hours. As can be seen in the micrograph, there are four phases, Nb/Nb3-xAl/Nb2-xAl/NbAl3, present in the film at this stage of the reaction. The composition of each of the four regions marked 1-4 was obtained by EDX analysis. The absolute concentration in each region could not be determined due to the lack of thickness and geometry parameters that were required to make the necessary absorption and fluorescence corrections.

Transmission Electron Microscopy of Epitaxial silicides grown by ultra high vacuum deposition

1989 ◽  
Vol 47 ◽  
pp. 462-463
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Diffraction ◽  
High Vacuum ◽  
High Energy ◽  
Energy Electron ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Transmission Electron

The silicides CoSi2 and NiSi2 are both metallic with the fee flourite structure and lattice constants which are close to silicon (1.2% and 0.6% smaller at room temperature respectively) Consequently epitaxial cobalt and nickel disilicide can be grown on silicon. If these layers are formed by ultra high vacuum (UHV) deposition (also known as molecular beam epitaxy or MBE) their thickness can be controlled to within a few monolayers. Such ultrathin metal/silicon systems have many potential applications: for example electronic devices based on ballistic transport. They also provide a model system to study the properties of heterointerfaces. In this work we will discuss results obtained using in situ and ex situ transmission electron microscopy (TEM).In situ TEM is suited to the study of MBE growth for several reasons. It offers high spatial resolution and the ability to penetrate many monolayers of material. This is in contrast to the techniques which are usually employed for in situ measurements in MBE, for example low energy electron diffraction (LEED) and reflection high energy electron diffraction (RHEED), which are both sensitive to only a few monolayers at the surface.

Exciton dynamics in thick GaN MOVPE epilayers deposited on sapphire.

1997 ◽  
Vol 2 ◽  
Author(s):  
J. Allègre ◽  
P. Lefebvre ◽  
J. Camassel ◽  
B. Beaumont ◽  
Pierre Gibart
Keyword(s):  
Layer Thickness ◽  
Buffer Layers ◽  
Rate Equations ◽  
Time Resolved ◽  
Versus Layer ◽  
Level Model ◽  
Shallow Impurities ◽  
Aln Buffer ◽  
Time Resolved Photoluminescence

Time-resolved photoluminescence spectra have been recorded on three GaN epitaxial layers of thickness 2.5 μm, 7 μm and 16 μm, at various temperatures ranging from 8K to 300K. The layers were deposited by MOVPE on (0001) sapphire substrates with standard AlN buffer layers. To achieve good homogeneities, the growth was in-situ monitored by laser reflectometry. All GaN layers showed sharp excitonic peaks in cw PL and three excitonic contributions were seen by reflectivity. The recombination dynamics of excitons depends strongly upon the layer thickness. For the thinnest layer, exponential decays with τ ~ 35 ps have been measured for both XA and XB free excitons. For the thickest layer, the decay becomes biexponential with τ1 ~ 80 ps and τ2 ~ 250 ps. These values are preserved up to room temperature. By solving coupled rate equations in a four-level model, this evolution is interpreted in terms of the reduction of density of both shallow impurities and deep traps, versus layer thickness, roughly following a L−1 law.

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