In-Situ TEM Observations of Different Growth Modes of Small Iron Particles on Sapphire

1980 ◽  
Vol 38 ◽  
pp. 402-403
Author(s):  
R. Anton ◽  
K. Heinemann
Keyword(s):  
Electron Beam ◽  
Width Ratio ◽  
In Situ Tem ◽  
Video Tape ◽  
Growth Modes ◽  
Transmission Electron ◽  
Special Direction ◽  
Substrate Temperatures ◽  
Kinetics Of

An in-situ study was performed of the growth kinetics of individual crystallites during the deposition of iron onto electron-transparent singlecrystalline α-Al2O3 (sapphire) substrates. Clean sapphire films were produced in-situ under UHV conditions by electron-beam induced crystallization of amorphous Al2O3 (1). Iron was electron-beam vapor-deposited at constant rates (0.2-0.5 nm/min) and elevated substrate temperatures (750 – 900°C) immediately following the crystallization. The nucleation, growth, and eventual coalescence of the metal particles were observed in-situ by transmission electron microscopy and recorded on video tape at 30 frames per second. In fig. 1, a growth and coalescence sequence of several Fe-particles on [100]-α-Al2O3 is shown. The images were selected and photographed from the TV monitor during video playback. The particles marked with letters were analyzed in detail. Noteworthy is that particle A (after about 30 min. of growth) started a rapid increase of its length-to-width ratio. Particle H, formed in a coalescence event, exhibited a preferred growth in a special direction, presumably in order to develop a certain crystallographic habit. Particle K developed a fast lateral growth ab-initio and remained a thin platelet until it coalesced with a neighboring particle about 25 min. after the beginning of the deposition.

Growth kinetics of Al2Cu in an Al-1.5Cu thin film by in Situ TEM

1993 ◽  
Vol 51 ◽  
pp. 1172-1173
Author(s):  
M. Park ◽  
S.J. Krause ◽  
S.R. Wilson
Keyword(s):  
Thin Film ◽  
In Situ Tem ◽  
Collector Plate ◽  
Transmission Electron ◽  
Device Processing ◽  
Corrosion Susceptibility ◽  
Precipitation Phenomena ◽  
Semiconductor Chips ◽  
Kinetics Of

Cu alloying in Al interconnection lines on semiconductor chips improves their resistance to electromigration and hillock growth. Excess Cu in Al can result in the formation of Cu-rich Al2Cu (θ) precipitates. These precipitates can significantly increase corrosion susceptibility due to the galvanic action between the θ-phase and the adjacent Cu-depleted matrix. The size and distribution of the θ-phase are also closely related to the film susceptibility to electromigration voiding. Thus, an important issue is the precipitation phenomena which occur during thermal device processing steps. In bulk alloys, it was found that the θ precipitates can grow via the grain boundary “collector plate mechanism” at rates far greater than allowed by volume diffusion. In a thin film, however, one might expect that the growth rate of a θ precipitate might be altered by interfacial diffusion. In this work, we report on the growth (lengthening) kinetics of the θ-phase in Al-Cu thin films as examined by in-situ isothermal aging in transmission electron microscopy (TEM).

In situ tEM observation of C49 to C54 TiSi2 transformation

1992 ◽  
Vol 50 (2) ◽  
pp. 1356-1357
Author(s):  
K. Barmak ◽  
L.E. Levine ◽  
D.A. Smith ◽  
Y. Komemt
Keyword(s):  
High Resistivity ◽  
In Situ Tem ◽  
Video Tape ◽  
Furnace Annealing ◽  
Plan View ◽  
Transmission Electron ◽  
In Situ Heating ◽  
Face Centered ◽  
Si Wafer

The reaction of thin films of Ti with Si results in the formation of the high resistivity (≃150 μΩcm) base-centered orthorhombic C49 phase prior to the low resistivity (≃15-20 μΩcm) face-centered orthorhombic C54 phase. In our experiments, 30 nm of Ti was evaporated onto a < 100 > oriented Si wafer cleaned in a 10:1 H2O:HF solution. The wafer had been previously implanted with As to a dose of 5×l015 cm−2. Mixed C49/C54 phase films were obtained by furnace annealing at 700°C for 10 min. Plan view transmission electron microscopy (TEM) specimens were prepared by dimpling and etching in a 10:6:6 HNO3:HF:CH3COOH solution. The sample was initially studied in a JEOL 4000FX and in situ heating experiments were carried out in a Philips 430 operating at 300 kV. The progress of the transformation was recorded on video tape. The temperature was raised relatively quickly to 700°C and then more slowly to 750°C.

In situ TEM studies of deformation and fracture

1989 ◽  
Vol 47 ◽  
pp. 622-623
Author(s):  
I.M. Robertson ◽  
T.C. Lee ◽  
D.K. Dewald ◽  
H.K. Birnbaum
Keyword(s):  
Grain Boundary ◽  
Video Camera ◽  
In Situ Tem ◽  
Video Tape ◽  
Slip Systems ◽  
Camera System ◽  
Dynamic Events ◽  
Transmission Electron ◽  
Deformation And Fracture

The in-situ TEM straining technique has been used to investigate the micromechanisms of deformation and fracture in several ductile and semi-brittle systems. Attention has been focussed on the dislocation structures ahead of advancing cracks and on the interaction between lattice dislocations and grain boundaries.The deformation experiments were performed in-situ in a transmission electron microscope equipped with a video camera system. The dynamic events were recorded on video tape with a time resolution of l/30th of a second. Static interactions were recorded using the regular microscope plate system. The straining stage deforms the samples in Mode I and can operate at a displacement rate of 4 in sec-1.An example of one of the possible interactions between lattice dislocations and a ∑- 3 ([ll)/60°) grain boundary in 310 stainless steel is shown in the micrograph in Figure 1. The dislocations on slip systems A (a/2[110)1 (ll) 1 ) and B (a/2[101] (11) 1 ) impinge on the grain boundary, generating slip systems C (a/2[l0) 2/(111) 2) and D (a/2[l0) 2/(111) 2). To understand this effect three conditions were considered:

Kinetics of Copper Grain Growth During Nitridation of Cu-Cr and Cu-Ti Thin Films by In Situ Tem

1994 ◽  
Vol 337 ◽  
Author(s):  
Z. Atzmon ◽  
R. Sharma ◽  
S. W. Russell ◽  
J.W. Mayer
Keyword(s):  
Thin Films ◽  
Growth Stages ◽  
In Situ Tem ◽  
Initial Growth ◽  
Transmission Electron ◽  
Diffusion Controlled ◽  
Cr System ◽  
Rate Limiting ◽  
Kinetics Of

ABSTRACTCo-deposited Cu-Cr and Cu-Ti thin films were heated at various temperatures in an ammonia ambient in an environmental cell placed into the column of a transmission electron microscope (TEM). The reaction dynamics were observed in situ and recorded on a videotape using a TV camera with 1/30 second time resolution. Nitridation of chromium and titanium was accompanied by the nucleation and growth of copper particles starting at 370 and 580°C, respectively. It was found that in the Cu-Ti system at a temperatures regime of 370-400°C the growth rate behaves under a parabolic law; namely, the process is controlled by diffusion of Cu through the nitride matrix. However, for the Cu-Cr system at temperatures of 610-630°C two growth regimes were observed. In the initial growth stages, the surface reaction is rate-limiting, while for longer nitridation times, growth is diffusion-controlled.

In Situ Tem Analysis of TiSi2 C49-C54 Transformations During Annealing

1996 ◽  
Vol 441 ◽  
Author(s):  
L. M. Gignac ◽  
V. Svilan ◽  
L. A. Clevenger ◽  
C. Cabral ◽  
C. Lavoie
Keyword(s):  
Nucleation Density ◽  
In Situ Tem ◽  
Video Tape ◽  
X Ray Diffraction ◽  
Tem Analysis ◽  
Transmission Electron ◽  
Varying Length ◽  
Transformation Front ◽  
Individual Line

AbstractIn situ transmission electron microscope (TEM) observations of TiSi2 C49-to-C54 phase transformations were recorded on video tape and photographic negatives, and transformation front velocities (vTF) were measured from the data. The samples studied in this work include: C49-TiSi2 blanket films and 0.2 μm wide, 7 mm long lines on undoped poly-Si and 0.13 μm wide, 10 μm long lines on either B- or As-doped poly-Si. The in situ TEM analysis showed that blanket TiSi2 films on undoped poly-Si fully transformed at 830°C and had an average vTF of 0.5 ± 0.2 μm/s. The transformation occurred from a sparse nucleation density of ˜0.1 site/μm2. The 0.2 μm wide lines transformed at temperatures greater than 885°C, and the average vTF was 1.1 ± 0.2 μm/sec. Agglomeration started for both the blanket film and the 0.2 μm wide lines at temperatures above 900°C. In situ x-ray diffraction (XRD) analyses of C49-TiSi2 on B- and As-doped poly-Si showed that blanket films completely transformed to C54-TiSi2 at T = 835–843°C, but 0.13 μm wide, varying length lines did not fully transform, even when rapid thermal annealed to 1025°C. From in situ TEM analysis of 0.13 μm wide, 10 μm long C49-TiSi2 lines on B-doped poly-Si, a distinct transformation was not observed. Instead, the lines slowly agglomerated, and electron diffraction of the agglomerated regions showed that the film had transformed to C54-TiSi2. An individual line either 1) completely transformed and agglomerated or 2) remained as C49-TiSi2 and did not agglomerate. Approximately 85% of all lines transformed. In situ TEM analysis of 0.13 μm wide, 10 μm long lines of C49-TiSi2 on As-doped poly-Si also showed an indistinct transformation to the C54 phase along with agglomeration, and 100% of the lines transformed.

In-Situ TEM Observations of Surface Roughening and Defect Formation in Lattice Mismatched Heteroepitaxial Thin Films

1997 ◽  
Vol 505 ◽  
Author(s):  
Cengiz S. Ozkan ◽  
William D. Nix ◽  
Huajian Gao
Keyword(s):  
Thin Films ◽  
Defect Formation ◽  
High Vacuum ◽  
Surface Roughening ◽  
In Situ Tem ◽  
Thick Sample ◽  
Transmission Electron ◽  
Sample Preparation Procedure ◽  
Kinetics Of

ABSTRACTThis paper focuses on in-situ transmission electron microscopy observations of surface roughening and defect formation in heteroepitaxial Sil−xGex thin films. Annealing experiments have been carried out in-situ in the microscope under a high vacuum environment. We comment on the sample preparation procedure for in-situ TEM experiments and explain the importance of having a sufficiently thick sample to have the stress state in the film unaltered. Experimental results of in-situ surface roughening are presented for suberitically and supercritically thick Sil−xGex films. We found that, in a vacuum environment, the kinetics of surface roughening and the resulting surface morphology are much different than in a hydrogen environment.

An In-Situ TEM-Cathodoluminescence Study of Electron Beam Degradation of Luminescence from GaN and In0.1Ga0.9N Quantum Wells

2002 ◽  
Vol 743 ◽  
Author(s):  
Nicholas M. Boyall ◽  
Ken Durose ◽  
Ian M. Watson
Keyword(s):  
Electron Beam ◽  
Quantum Wells ◽  
Electron Beam Irradiation ◽  
In Situ Tem ◽  
Beam Irradiation ◽  
Transmission Electron ◽  
Transmission Electron Microscope Analysis ◽  
Electron Microscope Analysis ◽  
Cathodoluminescence Study

ABSTRACTThe effect of electron beam irradiation on the cathodoluminescence (CL) emission from In0.1Ga0.9N/GaN single quantum wells (QW) has been investigated by in-situ measurement of CL in a transmission electron microscope. Analysis of CL quenching over 600s showed that the QW luminescence decayed more quickly than the barrier emission. Both the In0.1Ga0.9N and GaN CL decay curves could be fitted to a simple recombination based model suggesting the decay was due to the introduction of non-radiative centres.

In situ study of electron beam-induced chemical vapor deposition of Au in an environmental TEM

1995 ◽  
Vol 53 ◽  
pp. 256-257
Author(s):  
J. Drucker ◽  
R. Sharma ◽  
J. Kouvetakis ◽  
K.H.J. Weiss
Keyword(s):  
Electron Beam ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Quantum Effect ◽  
Line Drawing ◽  
Chemical Vapor ◽  
Environmental Cell ◽  
Engineering Changes ◽  
Kinetics Of

Patterning of metals is a key element in the fabrication of integrated microelectronics. For circuit repair and engineering changes constructive lithography, writing techniques, based on electron, ion or photon beam-induced decomposition of precursor molecule and its deposition on top of a structure have gained wide acceptance Recently, scanning probe techniques have been used for line drawing and wire growth of W on a silicon substrate for quantum effect devices. The kinetics of electron beam induced W deposition from WF6 gas has been studied by adsorbing the gas on SiO2 surface and measuring the growth in a TEM for various exposure times. Our environmental cell allows us to control not only electron exposure time but also the gas pressure flow and the temperature. We have studied the growth kinetics of Au Chemical vapor deposition (CVD), in situ, at different temperatures with/without the electron beam on highly clean Si surfaces in an environmental cell fitted inside a TEM column.

In situ TEM measurements of the electrical properties of interface dislocations

1992 ◽  
Vol 50 (2) ◽  
pp. 1338-1339
Author(s):  
F. M. Ross ◽  
R. Hull ◽  
D. Bahnck ◽  
J. C. Bean ◽  
L. J. Peticolas ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Electronic Device ◽  
In Situ Tem ◽  
Device Performance ◽  
Misfit Dislocations ◽  
Electrical Characteristics ◽  
Strained Layer ◽  
Transmission Electron ◽  
Interfacial Dislocations

We describe an investigation of the electrical properties of interfacial dislocations in strained layer heterostructures. We have been measuring both the structural and electrical characteristics of strained layer p-n junction diodes simultaneously in a transmission electron microscope, enabling us to correlate changes in the electrical characteristics of a device with the formation of dislocations.The presence of dislocations within an electronic device is known to degrade the device performance. This degradation is of increasing significance in the design and processing of novel strained layer devices which may require layer thicknesses above the critical thickness (hc), where it is energetically favourable for the layers to relax by the formation of misfit dislocations at the strained interfaces. In order to quantify how device performance is affected when relaxation occurs we have therefore been investigating the electrical properties of dislocations at the p-n junction in Si/GeSi diodes.

In situ TEM Studies of agglomeration of sub-nanometer Ru layers in Ru/C multilayers

1992 ◽  
Vol 50 (1) ◽  
pp. 256-257
Author(s):  
Tai D. Nguyen ◽  
Ronald Gronsky ◽  
Jeffrey B. Kortright
Keyword(s):  
Layered Structure ◽  
Driving Force ◽  
High Energy ◽  
Superior Performance ◽  
In Situ Tem ◽  
Rayleigh Instability ◽  
Practical Applications ◽  
Transmission Electron ◽  
Diffraction Patterns

Nanometer period Ru/C multilayers are one of the prime candidates for normal incident reflecting mirrors at wavelengths < 10 nm. Superior performance, which requires uniform layers and smooth interfaces, and high stability of the layered structure under thermal loadings are some of the demands in practical applications. Previous studies however show that the Ru layers in the 2 nm period Ru/C multilayer agglomerate upon moderate annealing, and the layered structure is no longer retained. This agglomeration and crystallization of the Ru layers upon annealing to form almost spherical crystallites is a result of the reduction of surface or interfacial energy from die amorphous high energy non-equilibrium state of the as-prepared sample dirough diffusive arrangements of the atoms. Proposed models for mechanism of thin film agglomeration include one analogous to Rayleigh instability, and grain boundary grooving in polycrystalline films. These models however are not necessarily appropriate to explain for the agglomeration in the sub-nanometer amorphous Ru layers in Ru/C multilayers. The Ru-C phase diagram shows a wide miscible gap, which indicates the preference of phase separation between these two materials and provides an additional driving force for agglomeration. In this paper, we study the evolution of the microstructures and layered structure via in-situ Transmission Electron Microscopy (TEM), and attempt to determine the order of occurence of agglomeration and crystallization in the Ru layers by observing the diffraction patterns.

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