Journal Article Is It Feasible To Routinely Check The Dopant Profiling Via Off-Axis Electron Holography For An IC Failure Analysis Laboratory? Get access KW Lee, KW Lee Samsung Electronics Co, Hwasung-City, Gyeonggi-Do, Korea 449-711 Search for other works by this author on: Oxford Academic Google Scholar HJ Park, HJ Park Samsung Electronics Co, Hwasung-City, Gyeonggi-Do, Korea 449-711 Search for other works by this author on: Oxford Academic Google Scholar YC Wang, YC Wang FEI Company, Hillsboro, OR 97124 Search for other works by this author on: Oxford Academic Google Scholar BK Park, BK Park Samsung Electronics Co, Hwasung-City, Gyeonggi-Do, Korea 449-711 Search for other works by this author on: Oxford Academic Google Scholar Sean Da, Sean Da FEI Company, Hillsboro, OR 97124 Search for other works by this author on: Oxford Academic Google Scholar YN Kim, YN Kim Samsung Electronics Co, Hwasung-City, Gyeonggi-Do, Korea 449-711 Search for other works by this author on: Oxford Academic Google Scholar JS Kim, JS Kim Samsung Electronics Co, Hwasung-City, Gyeonggi-Do, Korea 449-711 Search for other works by this author on: Oxford Academic Google Scholar E Van Cappellen, E Van Cappellen FEI Company, Hillsboro, OR 97124 Search for other works by this author on: Oxford Academic Google Scholar SM Chon SM Chon Samsung Electronics Co, Hwasung-City, Gyeonggi-Do, Korea 449-711 Search for other works by this author on: Oxford Academic Google Scholar Microscopy and Microanalysis, Volume 9, Issue S02, 1 August 2003, Pages 774–775, https://doi.org/10.1017/S1431927603443870 Published: 21 July 2003

A new method to determine the concentration of germanium in Si(1-x) Ge(x) single crystals is presented. It is based on extinction distance measurements by means of convergent beam electron diffraction (CBED). The two-beam condition CBED intensity oscillation (the so-called rocking curve) is measured for the 004 diffracted beam and compared with a numerical simulation. Using the two-beam dynamical diffraction approximation theory, this approach yields very precise values for both specimen thickness and effective extinction distance (Ultramicroscopy 87 (2001) 5). First a theoretical extinction distance zetag(x) for strain relaxed Si(1-x)Ge(x) is calculated assuming a solid solution and using tabulated atomic scattering factors of silicon and germanium atoms. It is found that for single crystals zetag(x) decreases from 156 nm in pure silicon to 90 nm in pure germanium. Measurements on calibrated strain relaxed SiGe layers with variable germanium concentrations show an excellent agreement between experimental and calculated extinction distances zetag(x). As a consequence the experimental extinction distance zetag(x) becomes an indirect measure of the germanium concentration with a 1-2 at % sensitivity. The method turns out to be insensitive to strain as experimental zetag(x) values obtained on strained SiGe layers fit the theoretical extinction distance curve calculated for strain relaxed SiGe.

In many new application areas it is necessary to combine atomic resolution imaging with atomic level chemical and crystallographic analysis. The new applications include microbiology, nanotubes, smart materials and sensor initiatives, and the myriad semiconductor fields. Along with these there are many other valuable applications in older and more established technologies such as chemicals, catalysis, pigments and construction materials for chemical plants, airplanes, pipelines, power generation, and other aspects of societal infrastructure. Analysis down to the atomic level will help to solve recalcitrant problems and open up some reluctant opportunities in these fields. They can be very effective in resolving important and long standing issues with huge potential monetary and societal costs and benefits. Key aspects of environmentally sensitive corrosion and pollution control may also require the support of similarly sophisticated imaging and microanalysis.We think the capabilities of a new generation high performance instrument should include atomic resolution coherent TEM imaging and also incoherent atomic number (Z) contrast high angle annular dark field (HAADF) STEM imaging.

A new method for measuring thickness and extinction distance of single crystals based on computed adjustment of measured and calculated CBED pattern intensity profiles is presented and discussed. The experimental beam intensity distribution is measured from an energy filtered CBED pattern recorded on a CCD camera. The calculated profile is based on dynamical diffraction theory, and with the two-beam approximation the analytical expression contains only two free parameters: specimen thickness t and extinction distance xig. Parameter refinement through minimization of the difference between experimental and calculated intensity profiles is carried out using Origin 5.0 software from Microcal. The iterative procedure always converges to a unique solution in a few seconds, yielding an accurate value for both thickness and extinction distance. The method is extensively tested on silicon using the (0 0 4) Bragg reflection. On specimens in the usual TEM thickness range, the method gives result similar to the conventional (P.M. Kelly et al., Phys. Stat. Sol. A31 (1975) 771; S.M. Allen, Philos. Mag. A 43 (1981) 325) graphical methods, both based on the measurement of fringe spacing. Moreover, it is shown that the calculation matches perfectly both the positions of the minimums and maximums as well as the amplitude of maximums. For any single intensity profile, specimen thickness and extinction distance can be determined with a precision of about 0.2%. A statistical comparison of our method with the Kelly and Allen techniques, based on more than 50 experiments, shows an improvement in measured extinction distance dispersion. Using 197 keV electrons, and liquid-nitrogen cryo-holder, the new technique yields an experimental value of 161+/-3 nm for the extinction distance for silicon with the (0 0 4) Bragg reflection. The equivalent tabulated value at 0 K is about 156 nm. Using the Kelly and Allen methods, the extinction distance is found to be 162+/-6 nm. The improvement in precision is a direct consequence of matching the intensity profile envelope, which contains information on the extinction distance. Also the accuracy of thickness determination is improved and is around 0.5 to 1% for common specimen thickness. The minimum measurable sample thickness is shown to be two to three times thinner than with the Kelly and Allen methods (0.3 xig, as opposed to 0.8 xig). With no independent calculation of the extinction distance needed, the method is also applicable on unknown crystals. The method is fast, simple and can be easily automated.

It all started in Berlin in 1931 where Dr. Ernst Ruska built the first TEM with 2 magnetic lenses. Three years later a third lens was added and a resolution of l00nm was demonstrated, just enough to beat the light microscope by a factor of two. His achievements and vision was acknowledged and celebrated in 1986 when he was awarded the Nobel Prize for Physics. Philips’ commitment to electron microscopy dates back to the mid-1930s, when it collaborated in EM research programs with universities in the UK and the Netherlands. in 1949, the company introduced its first EM production unit, the EM 100 transmission electron microscope, which already was a significant step forward in terms of ease of use and reliability. In fifty years the TEM has come a long way; enumerating all the milestones would be too lengthy.

Introduction SiGe epitaxy on Si has been extensively studied, for semiconductor gap modeling and band structure engineering. Quantitative measurement of the Ge concentration is not a trivial exercise at the microscopic level, where classical tools such as X-Ray diffraction, ellipsometry and SIMS cannot be used. A new quantitative microanalytical technique is proposed based on extinction distance measurements using Convergent Beam Electron Diffraction (CBED) combined with dynamical diffraction simulations. A Ge concentration accuracy of less than 2% is demonstrated on strain relaxed SiGe epitaxial layers. Experiment Unstrained SiGe epitaxial layers are analyzed for different Ge concentrations, with two-beam CBED, using the transmitted and the 004 diffracted disc. Energy filtered CBED patterns are acquired at 197 keV with a Philips CM 200 FEG transmission electron microscope, using the Ik x Ik CCD camera of the Gatan GIF energy filter. A liquid nitrogen cryo-holder is used, to sharpen up the CBED patterns and to avoid contamination and degradation of the samples.

1. Introduction The FIB (focused ion beam) is now widely accepted as the most site-specific TEM preparation tool and as such proves to be highly valuable when analysing ULSI devices. However, using high-energy Gallium ions for milling induces amorphization of the crystal surfaces. A method able to quantify this surface alteration on silicon using a combination of CBED (convergent beam electron diffraction) and EELS (electron energy loss spectroscopy) is presented. CBED is a powerful tool that also can generate an accurate measure of crystal thickness. EELS can yield the total sample thickness, so from the difference the combined amorphous layers can be assessed. Two sets of application results are presented: the first one is obtained on a FIB thinned sample using an ion energy of 50 keV and the second set of results confirms the validity of the proposed method on a mechanically polished specimen with no subsequent ion milling.

A quantitative high resolution transmission electron microscopy (HRTEM) study of amorphous materials has been undertaken in the study-case of amorphous germanium. The analysis consists in a modeling of amorphous germanium, suitable to run multislice calculations, and to simulate HRTEM images, the computed diffractograms of which are numerically compared to experimental ones obtained from a through-focus series taken on a dedicated high resolution microscope equipped with a field-emission gun. The final aim of this work is to quantify the structural information that can be retrieved from HRTEM images of amorphous materials. As a preliminary step, the coefficient of spherical aberration ( C s ) of the microscope, as well as the amount of defocus ( δf ) of each micrograph have to be known. The aim of the first part of this paper is to determine, as precisely as possible, these parameters. A new method is proposed, as an alternative to usual methods based on least-squares fittings of the zeros of the experimental diffractograms: the theoretical diffractograms are computed, and numerically compared, through the minimization of a profile agreement factor depending upon the C s and δf values, and the thickness of the amorphous film, to the experimental ones. The critical steps of this approach are the modeling of the scattering of the amorphous material, and, more drastically, the estimation of the experimental thickness, which influences significantly the values of C s and δfs .

Electron diffraction has allowed the determination of the superlattice of Ba3UO6. The structure is a commensurate one-dimensional long-period superstructure of the perovskite structure, the long period being oriented along the [351]c direction.