Stability of the T2 phase during low-dose ion milling

Recent studies have shown that the T2 (Al6CuLi3) phase particles in dilute Al-Li-Cu alloys transform to microcrystalline aggregates during TEM examination, during ion-beam thinning, or during in- situ heating in the TEM. Other studies, however, have noted that the T2 phase particles exhibit an ‘apparent’ five-fold symmetry suggesting that microcrystalline or twinned regions, rather than ‘single crystal’ regions, were responsible for the five-fold diffraction patterns. As a consequence, additional work was considered necessary to investigate further the stability of the T2 phase in dilute Al-Li-Cu alloys.The 3-mm diameter TEM disc specimens were prepared from a specially melted Al-2.5%Li-2.5%Cu alloy produced by conventional procedures. The TEM specimen thermal treatment and electropolishing procedures were previously reported. The electropolished disc specimens were examined in a JEOL 200CX microscope operated at 200 kV. Selected disc specimens containing the T2 phase were then subjected to ion beam thinning in a Gatan precision ion-milling system, operated with an argon ion beam, at accelerating voltage of 6 kV and a beam current of lμA.

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Influence of ion-milling on the T2 phase in Al-2.5%Li-2.5%Cu alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153415 ◽

1989 ◽

Vol 47 ◽

pp. 288-289

Author(s):

J. R. Reed ◽

D. J. Michel ◽

P. R. Howell

Keyword(s):

Thin Foil ◽

Icosahedral Symmetry ◽

Ion Milling ◽

Cu Alloy ◽

Thin Foils ◽

Heat Treated ◽

Aluminum Solid Solution ◽

In Situ Heating ◽

The Stability

The Al6Li3Cu (T2) phase, which exhibits five-fold or icosahedral symmetry, forms through solid state precipitation in dilute Al-Li-Cu alloys. Recent studies have reported that the T2 phase transforms either during TEM examination of thin foils or following ion-milling of thin foil specimens. Related studies have shown that T2 phase transforms to a microcrystalline array of the TB phase and a dilute aluminum solid solution during in-situ heating in the TEM. The purpose of this paper is to report results from an investigation of the influence of ion-milling on the stability of the T2 phase in dilute Al-Li-Cu alloy.The 3-mm diameter TEM disc specimens were prepared from a specially melted Al-2.5%Li-2.5%Cu alloy produced by conventional procedures. The TEM specimens were solution heat treated 1 h at 550°C and aged 1000 h at 190°C in air to develop the microstructure. The disc specimens were electropolished to achieve electron transparency using a 20:80 (vol. percent) nitric acid: methanol solution at -60°C.

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Fast Preparation of Ultrathin FIB Lamellas for MEMs-Based In Situ TEM Experiments

Materials Science Forum ◽

10.4028/www.scientific.net/msf.850.722 ◽

2016 ◽

Vol 850 ◽

pp. 722-727 ◽

Cited By ~ 2

Author(s):

Hui Wang ◽

Shang Gang Xiao ◽

Qiang Xu ◽

Tao Zhang ◽

Henny Zandbergen

Keyword(s):

Sample Preparation ◽

Focused Ion Beam ◽

Preparation Method ◽

Ion Beam ◽

Metallic Alloy ◽

In Situ Tem ◽

Ion Milling ◽

Electrochemical Polishing ◽

Argon Ion

The preparation of thin lamellas by focused ion beam (FIB) for MEMS-based in situ TEM experiments is time consuming. Typically, the lamellas are of ~5μm*10μm and have a thickness less than 100nm. Here we demonstrate a fast lamellas’ preparation method using special fast cutting by FIB of samples prepared by conventional TEM sample preparation by argon ion milling or electrochemical polishing methods. This method has been applied successfully on various materials, such as ductile metallic alloy Ti68Ta27Al5, brittle ceramics K0.5Na0.5NbO3-6%LiNbO3 and semiconductor Si. The thickness of the lamellas depends on the original TEM sample.

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A RMEED and SEM investigation of metal oxidation phenomena

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109367 ◽

1978 ◽

Vol 36 (1) ◽

pp. 444-445

Author(s):

G.G. Hembree ◽

J.M. Cowley ◽

M.A. Otooni

Keyword(s):

Ion Beam ◽

Pure Copper ◽

Reaction Times ◽

Copper Films ◽

Metal Oxidation ◽

Low Oxygen ◽

In Situ Study ◽

Diffraction Patterns ◽

Argon Ion

We have recently completed an in-situ study of the reaction of copper thin films at low oxygen pressures (10-5 torr) and relatively high temperatures (500-700°C).These conditions allow convenient observation over reasonably short reaction times in our UHV RMEED/SEM instrument(1).Epitaxially grown (111) copper films of approximately 100nm thickness were prepared in a conventional HV system and placed in the UHV system as produced on their mica substrates. Epitaxy was confirmed by TED/TEM on pieces of the film which were stripped off the substrate and by the electron channeling patterns observed in the SEM. Initial treatment in the UHV system included annealing at 300°C for several hours and a final anneal at 500°C for one hour. In one case the film was sputter cleaned with a 700eV argon ion beam between the two annealing processes. Some oxide nuclei of various sizes were observed after this treatment.After the initial cleaning pure copper reflection diffraction patterns as in Fig.1 were recorded up to the sixth order.

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Reduction of the Damage Induced in an Fib-Fabricated X-Tem Specimen

MRS Proceedings ◽

10.1557/proc-523-39 ◽

1998 ◽

Vol 523 ◽

Cited By ~ 1

Author(s):

N. I. Kato ◽

K. Tsujimoto ◽

N. Miura

Keyword(s):

Focused Ion Beam ◽

Crystalline Silicon ◽

Ion Beam ◽

Side Wall ◽

Beam Current ◽

Wet Etching ◽

Ion Milling ◽

Cross Sectional ◽

20 Nm ◽

Argon Ion

AbstractIn focused ion beam (FIB) fabrication of cross-sectional transmission electron microscopy (X-TEM) specimens, highly accelerated ion beams sometimes cause serious damage. The damage can be induced in both the specimen surface and in the side walls. We used X-TEM observations to investigate the side-wall damage induced by FIB fabrication in crystalline silicon. The damaged layer was found to be about 20 nm thick in the case of 30-keV FIB etching. We tried to reduce the damage by several methods, such as gas-assisted etching (GAE) with iodine, broad argon ion milling and wet etching. The damaged layer was 19 nm for GAE and 12 nm for argon ion milling with a beam current of 70 mA and the tilt angle between the beam and the specimen of 15 degrees. Wet etching using a mixture of nitric and hydrofluoric acid removes most of the damaged layer.

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Effects of Ion Beam Milling on Surface Topography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070862 ◽

1973 ◽

Vol 31 ◽

pp. 84-85

Author(s):

P.G. Pawar ◽

P. Duhamel ◽

G.W. Monk

Keyword(s):

Surface Topography ◽

Ion Beam ◽

Solid Material ◽

Beam Current ◽

Atomic Mass ◽

Micro Milling ◽

Ion Milling ◽

Controlled Atmospheres ◽

Milling Operations ◽

Sufficient Energy

A beam of ions of mass greater than a few atomic mass units and with sufficient energy can remove atoms from the surface of a solid material at a useful rate. A system used to achieve this purpose under controlled atmospheres is called an ion miliing machine. An ion milling apparatus presently available as IMMI-III with a IMMIAC was used in this investigation. Unless otherwise stated, all the micro milling operations were done with Ar+ at 6kv using a beam current of 100 μA for each of the two guns, with a specimen tilt of 15° from the horizontal plane.It is fairly well established that ion bombardment of the surface of homogeneous materials can produce surface topography which resembles geological erosional features.

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Low Energy Ar Ion Milling of FIB TEM Specimens from 14 nm and Future FinFET Technologies

10.31399/asm.cp.istfa2018p0241 ◽

2018 ◽

Author(s):

C.S. Bonifacio ◽

P. Nowakowski ◽

M.J. Campin ◽

M.L. Ray ◽

P.E. Fischione

Keyword(s):

Field Effect Transistor ◽

Focused Ion Beam ◽

Ion Beam ◽

Specimen Preparation ◽

Ion Milling ◽

Transmission Electron ◽

High Resolution Tem ◽

Effect Transistor ◽

20 Nm ◽

Argon Ion

Abstract Transmission electron microscopy (TEM) specimens are typically prepared using the focused ion beam (FIB) due to its site specificity, and fast and accurate thinning capabilities. However, TEM and high-resolution TEM (HRTEM) analysis may be limited due to the resulting FIB-induced artifacts. This work identifies FIB artifacts and presents the use of argon ion milling for the removal of FIB-induced damage for reproducible TEM specimen preparation of current and future fin field effect transistor (FinFET) technologies. Subsequently, high-quality and electron-transparent TEM specimens of less than 20 nm are obtained.

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In-Situ Dual Beam (FIBSEM) Techniques for Probe Pad Deposition and Dielectric Integrity Inspection in 0.2 μm Technology DRAM Single Cells

ISTFA 1999: Conference Proceedings from the 25th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa1999p0311 ◽

1999 ◽

Author(s):

Gunnar Zimmermann ◽

Richard Chapman

Keyword(s):

Electron Beam ◽

Single Cell ◽

Single Cells ◽

Ion Beam ◽

Gate Oxide ◽

Ion Milling ◽

Dual Beam ◽

Sem Imaging ◽

Innovative Techniques

Abstract Dual beam FIBSEM systems invite the use of innovative techniques to localize IC fails both electrically and physically. For electrical localization, we present a quick and reliable in-situ FIBSEM technique to deposit probe pads with very low parasitic leakage (Ipara < 4E-11A at 3V). The probe pads were Pt, deposited with ion beam assistance, on top of highly insulating SiOx, deposited with electron beam assistance. The buried plate (n-Band), p-well, wordline and bitline of a failing and a good 0.2 μm technology DRAM single cell were contacted. Both cells shared the same wordline for direct comparison of cell characteristics. Through this technique we electrically isolated the fail to a single cell by detecting leakage between the polysilicon wordline gate and the cell diffusion. For physical localization, we present a completely in-situ FIBSEM technique that combines ion milling, XeF2 staining and SEM imaging. With this technique, the electrically isolated fail was found to be a hole in the gate oxide at the bad cell.

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Reduction of Charging in Biological Electron Cryomicroscopy

Microscopy and Microanalysis ◽

10.1017/s1431927600008710 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 365-366

Author(s):

M.B. Sherman ◽

J. Brink ◽

W. Chiu

Keyword(s):

Electron Diffraction ◽

Ion Beam ◽

High Energy ◽

Carbon Layer ◽

Thin Layers ◽

Biological Macromolecules ◽

Electron Cryomicroscopy ◽

Obvious Effect ◽

Diffraction Patterns ◽

The Stability

High resolution imaging in electron cryomicroscopy of biological macromolecules is strongly affected by beam-induced charging1. Charging is often expressed in frozen or glucose-embedded specimens as an increase in apparent mass-thickness of the irradiated area. Another obvious effect of charging is blurring of both the unscattered beam and reflections in electron diffraction patterns recorded from crystalline specimens. Coating of ice-embedded specimens with a carbon layer helps to improve the stability of the ice and probably reduce charging of the specimen. Coating in a Gatan ion-beam coater (model 681) of glucose-embedded specimens with thin layers of various conductive materials did reduce charging but the specimens were damaged by the high energy ions used for the coating. In general, coating resulted in much weaker reflections in electron diffraction patterns obtained from coated crystals and faster resolution fall-off.We modified the Gatan coater by outfitting it with a new chamber that replaced the ion-beam deposition capability for thermal evaporation of carbon rods (Fig. 1).

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