In this paper, we apply a novel contactless method that we study to investigate the physical properties of the semiconductor materials. This method is based upon the measurement of the surface electron beam exciting potential (SEBEP) on the sample surface. Its advantages include: no direct sample contact or connection needed that is unlike the electron beam inducing current (EBIC) method; no potential barrier required from the measurement.

Electron probe irradiation can cause bending of the energy bands, variation of carriers and excitation of surface potential. The excited surface potential generates the SEBEP signal that can be detected by a SEBEP detector. It is necessary to emphasize that the electron beam can charge the surface that is under the oxide layer when it passes through the sample surface oxide layer.

It is known that the diffusion length L and the average lifetime τ of the non-equilibrium carries can be measured by other methods such as the cathodoluminescent method and the contacting method..

It is very important to study a new method of nondestructive internal microtomography of semiconductors and IC. in this paper, we report some research results that were obtained in resent years using nondestructive internal microtomography (NDIMT) to study semiconductor materials(SM) and microelectronic devices (MD) in SEM. Now we can apply this method to detect the microstructures and defects in the subsurface of SM. The conditions of microstructures and the defects being or not in the subsurface of SM used directly depend on the quality of MD. By attaching a special attachment that was devised based on the NDIMT to SEM we can perform nondestructive internal microtomographic visualization of the subsurface of SM the tested SM may be used latter to produce MD. in this way NDIMT may be used to select good quality SM which can then be used for research and production of MD. The product yield and reliabilities of MD can therefore be improved.

The formation of a silicon alloy has been achieved by electron beam irradiation of a nickel-silicon bilayer. This process, called SiDWEL1 , has been developed by Quantiscript. The nickel-silicon bilayer is very thin and the electron beam operates at low energy and current. Silicide formation occurred around the interaction volume of the electrons within the material. This paper describes the nature of the structures produced and the origin of the difficulties encountered with the characterization. The necessity of further analysis with TEM based techniques is highlighted.

Figure 1 presents a cross-section of a typical sample. The growth of silicide grains is induced by the e-beam irradiation of the stack for few microseconds. Nucieation is initiated by the diffusion of silicon atoms in nickel grains, induced by the heating arising from the electron beam interaction with the solid. A new phase is revealed by FE-SEM observation, after wet etching of the nickel film, as shown in figures 2 and 3.

GaN is a semiconductor material with promising applications in display and laser devices. GaNbased thin films have been grown by various methods and intensively investigated. Additionally, GaN nano particles have been prepared by various different methods. in this paper, we report our new finding of the structural modulation of GaN nano crystals induced by electron beam irradiation within a transmission electron microscope (TEM). The origin of the modulation structure is due to the ordering of N vacancies in the GaN nano crystals.

The GaN nano crystals were prepared by d.c arc plasma method. A Philips CM200 TEM with a field emission gun (FEG) operating at 200KV was used in this study. The GaN nano crystals normally show hexagonal shape (see Fig.la). Corresponding electron diffraction pattern along [0001] axis indicates the Wurtzite structure (see Fig. lb). It was unexpected that satellite reflections gradually appeared in the diffraction pattern after the GaN nano crystal had been exposed to the electron beam (see Fig.lc-d).

All scanning electron microscopes, whether they are in laboratory or on the production line, slowly lose performance as the instrument is used. This loss of performance is due to a whole array of contributing factors including misalignments, contamination and increases in source diameter. Identifying a loss in “sharpness” easily recognizes this performance decrease. Reference Material 8091 (RM 8091) is intended primarily for use in routinely checking the sharpness performance of scanning electron microscopes (Fig. 1). RM 8091 is designed to be used in conjunction with the SPECTEL SEM Monitor Program, the NIST Kurtosis program,3 or the University of Tennessee SMART program. RM 8091 is supplied as a small, approximately 2 mm x 2 mm diced semiconductor chip. This sample is capable of being mounted directly on to a wafer, wafer piece or specimen stub for insertion into a laboratory scanning electron microscope or wafer inspection scanning electron microscope.

There are many technical challenges to be overcome before controlled fusion reactions can be achieved. The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is being developed to initiate fusion reactions using the world's most powerful laser. Essential components of the Facility are the ultra pure silica (SiO2) lenses that focus the powerful laser beams on to the target. Irradiation with a high power laser has been observed to damage the silica lenses, resulting in the formation of defects. The ensuing degradation of the lens performance necessitates its replacement. It is therefore critical to characterize the induced defects and understand the laser damage initiation and evolution, so that damage mitigation strategies can be developed.

Cathodoluminescence (CL) microscopy and spectroscopy enables high spatial resolution and high sensitivity detection of defects in poorly conducting materials. It is therefore an ideal microanalytical technique with which to study laser irradiation-induced defects.

Millions of gallons of high-level radioactive waste are contained in underground tanks at U. S. Department of Energy sites such as Hanford and Savannah River. Most of the radioactivity is due to 137Cs and 90Sr, which must be extracted in order to concentrate the waste. An ion exchanger, crystalline silicotitanate IONSIV® IE911, is being considered for separation of Cs at the Savannah River Site (SRS). While the performance of this ion exchanger has been well characterized under normal operating conditions, Cs removal at slightly elevated temperatures, such as those that may occur in a process upset, is not clear. Our recent study indicates that during exposure to SRS simulant at 55°C and 80°C, an aluminosilicate coating formed on the exchanger surface. There was concern that the coating would affect its ion exchange properties. A LEO 982 field emission scanning electron microscope (FESEM) and an Oxford ISIS energy dispersive x-ray spectrometer (EDS) were used to characterize the coating.

In spite of commercial importance of polyethylene(PE), morphologies of melt crystallized PE have been rarely studied. Although, it was possible to observe polyethylene microstructure, they were based on the observation performed almost exclusively on thin films which were obtained either by casting samples between glass plates, or by microtoming the materials with transmission electron microscope(TEM). Despite the usefulness of TEM for detailed investigation of the polyethylene, it is not suitable for the structure characterization of the bulk samples, for examples, the characterization of a thick testpiece and commercial products of polyethylene itself. For such bulk specimen or thick sample, scanning electron microscope (SEM) is more useful, if the appropriate and reliable sample preparation method is applied.

In this study, we introduce a chemical etching technique for the investigation of melt crystallized polyethylene microstructure by SEM. Especially in this work we studied the characteristic properties and shapes of polyethylene banded spherulite which come from the melt s.

The introduction of organophilic layered silicates into a polyamide matrix significantly improves stiffness and strength [1,2]. Two methods are known to prepare such nanocomposites. For both methods cations such as sodium, potassium, magnesium or calcium, located in the interlayer galleries of the layered silicates must be exchanged by quaternary alkyl ammonium ions containing at least one alkyl chain and so rendering the originally hydrophilic into an organophilic silicate. in the insitu-method monomeric caprolactam is intercalated between the modified silicate interlayers and subsequently polycondensated to polyamide. By this method the silicates can be broken down into their nanoscale building blocks as can be shown by TEM and ESI (Fig. 1). Another more direct possibility to delaminate the silicates is melt mixing in an extruder. with both methods similar degrees of delamination can be achieved.

This paper presents some of our morphological results on polyamide containing organically modified montmorillonite.

Because of its superior cold formability, a great amount of IF steels is being produced by many steel manufacturers. Accordingly, numerous efforts have been made to understand the mechanism of improved plastic strain ratio in Ti-added IF steels1“3. Several mechanisms have been proposed to explain the effect of Ti on the deep drawability of these steels: l)the scavenging effect that is removing carbon and nitrogen from the solution by fixing them as stable precipitates, 2)promotion of (111) texture by fine dispersion of TiC precipitates, and 3)effects of substitutional elements in solid solution4. in spite of these advantages, Ti-added ultra low carbon steels have a disadvantage of high recrystallization temperature. Hayakawa et al.5have reported that recrystallization temperature is sharply rises with the increase in titanium content and reaches a peak when solute titanium is nil, and the acute recrystallization temperature is lowered with the decrease in amount of fine TiC precipitates.

Formation of acicular ferrite grains by dispersing non-metallic inclusions which can act as intragranular nucleation sites within austenite grain is proposed as a method to obtain refined grain structure in steels. The microstructure of acicular ferrite steel consists of fine interlocking ferrite plates nucleated on dispersed non-metallic inclusions. This acicular ferrite structure provides a desirable combination of high strength and good toughness because of its small plate thickness and interlocking microstruture. in Ti-containing low carbon steels, researchers proposed that Ti2O3 or MnS, among inclusions, is the most effective nucleant for intragranular ferrite because of the formation of Mn depleted zone(MDZ) around Ti2O3 or MnS particles. TiN is also reported as a nucleation site owing to the coherency between ferrite and TiN crystals. But It has not been a simple task to identify which inclusions and what mechanisms are really effective in the formation of intragranular acicular ferrite.

Upon hot strip mill of titanium Interstitial Free (IF) steels, during cooling from austenite to ferrite region, the level of interstitial elements not removed by steelmaking process is dropped down by Ti that combines with N, C and S. Some authors [1-3] have reported that the traditional precipitation sequence TiN, TiS, Ti4C2S2 and TiC occurs with freestanding particles formed by nucleation and growth processes. Other authors [4] have indicated that the transformation from TiS to Ti4C2S2 may be considered as a hybrid of shear and diffusion, i.e., faulted Ti8S9 (9R) + 10[Ti] + 9[C] → 41/2Ti4C2S2 (or H for its hexagonal crystal structure). At low temperature (≤930°C), the stabilization process continues through epitaxial growth of carbides on H phase. to study the evolution of precipitation upon hot strip mill conditions, samples of a Ti - IF steel were subjected to double straining tests [5] by means of a computerized hot torsion machine, at 1000 °C and 920 °C, with strain rate of 1 s-1 and interpass times ranging from 0.5 to 100 s.

TEM has been used for semiconductor device characterization since the 1980's, when Marcus and Cheng first demonstrated the feasibility and utility of applying TEM to semiconductors. The frequency of use of TEM has accelerated briskly due to the continual shrinkage of devices as predicted by Gordon Moore and now documented in the SIA roadmap (http://public.itrs.net/Home.htm). TEM use has also grown due to application of FIB techniques which make possible high precision cross-sections of specific structures. This relentless shrinking has resulted in difficulties in preparing suitable specimens. Many of the features and interfaces in a device may be curved rather than planar, and as the radius of curvature begins to approach the thickness of a TEM specimen, it can result in “geometrical blurring” of features, both for imaging and microanalysis. The origin of this blurring is illustrated in Figure 1, where it can be seen that a single electron may pass through two different features, and as a result, they are not resolved.

The microscopy to support process development of Si-based semiconductors has consistently required state-of-the-art instrumentation. As the industry strains to achieve 1 OOnm design rules, this requirement has never been more pronounced. This paper presents TEM, SEM and FIB examples with a focus on using the instrumentation near the performance limit.

Transmission Electron Microscopy - The high contrast and high resolution images provided by the TEM have made this “research instrument” into the mainstay of the semiconductor analysis laboratory. For the vast majority of samples, both plan view and cross sections, precious little tilt is required. For cross sections, +/- 3 degrees is usually adequate to bring the silicon into (110) orientation and plan views are commonly made from polycrystalline films, which benefit more from choosing the right thickness than from tilt. Under appreciated is the benefit of very high resolution polepieces which have superior spherical and chromatic aberration coefficients producing real improvements in image quality.

Electron beam induced current (EBIC) is the common term used in the semiconductor industry for the failure analysis and yield enhancement of semiconductor devices using SEM to electrically pinpoint leakage sites. EBIC is a useful technique for locating defects in diodes, transistors, and capacitors where the scanning electron microscope beam is used to generate a signal and the sample is the detector. Often during yield enhancement efforts the failure analyst is asked to determine the mechanism for which a PC structure (which may contain as many as a few hundred thousand structures in one device) is failing tests. Blind cross sections rarely give evidence of the failure mechanism. EBIC can be used to pinpoint the bad site which is then precision cross-sectioned using the focused ion beam (FIB).

When an electron beam impinges on a semiconductor such as silicon, electron-hole pairs are created when the incident beam transfers enough energy to promote an electron from the valance band to the conduction band.

The analytical needs in semiconductor technology have grown under the increasing demands imposed by reduced critical dimensions, increased wafer size, and complexity. Optical visualization, localization and counting of particles and defects has been extended to morphological and chemical characterization owing to the shifting balance from quality control to root-cause defect analysis. This becomes increasingly important because, via knowledge of the particle defect material plus the process/ hardware features, it leads to a direct path for the particle culprit and a methodical defect reduction procedure.

We present here specific examples from Applied Materials development, particularly related to particles formed during poly Si etch and during two different cleaning procedures (a) NF3 rf process chamber clean and (b) pre-clean (before subsequent deposition) of SiON film via Ar+ sputtering. These cases include identification of Br-based particles after poly-gate etch, and attempts to classify a variety of Al-containing particles of differing origins caused by too aggressive cleaning.

Rechargeable Lithium ion batteries are widely used as portable power source in communication and computer technology, prospective uses include medical implantable devices and electric vehicles. The safety and cycle life of Li ion batteries is improved over that of batteries containing metallic lithium anodes because the insertion of Li between the crystal layers of both electrodes was proved to be safer than the electroplating of Li onto a metallic Lithium anode. in Li-ion batteries, the charge transport is governed by the oscillation of Li ions between anode and cathode. They are sometimes called “rocking-chair“ batteries. The most common materials for these batteries are lithiated carbons for anodes, and transition metal oxides (LixCoO2) as cathodes.

LixCoO2 has an ordered rhombohedral Rm structure consisting of alternating layers of Co-O-Li-O-Co. The capacity and energy density of the batteries is limited by the amount of Li that can be stored in the anode and cathode materials.

The unique physical and chemical properties of AgX (X=C1, Br, I) emulsion microcrystals (optical, solid state, transport, chemical and spectral sensitizations and development) account for their use as basic light quanta detectors in practical photography for over 150 years. in spite of the advances made in other recording systems, especially in electronic imaging, contemporary AgX-based photographic materials are still superior in sensitivity and resolution. Although the replacement of AgX-based imaging systems by electronic imaging was already predicted 20 years ago, their current world manufacturing level is now larger than ever. However, in order to be successfully incorporated into digital and hybrid information technologies for the new Millennium, AgX-based photographic materials should further improve their quantum efficiency and image quality. in order to achieve these objectives, the key components should be intentionally modified with a focus primarily at the nanostructural level.

Transmission electron microscopes have been built along with and guided by technological opportunities since the last five decades. Even though there are some “workhorse” type of microscopes, these instruments are still more or less built from the technological viewpoint and less from the viewpoint of ease of use in a wide range of applications. On the other hand, leading edge applications are the drivers for the development and the use of leading edge technology. The result then is a “race horse” which is of very limited benefit in “Real world”.

During the last decade computers have been integrated to build microscope systems. in most cases, however, computers still have to deal with obsolete electron optical ray path designs and thus, have to be used more to overcome the problems of imperfect optics and bad design of ray paths than to provide optimized “Real world” capabilities.

In the last two decades, microscopy, in particular transmission electron microscopy, has moved from the research environment into industry. As such, the user requirements of the microscopes have changed. Previously, users required the highest performance in all aspects of microscopy e.g. imaging, analytical capabilities, with little regard to other factors. Today, additional requirements are being placed on areas such as ease of use, reliability, high throughput, expanded sample requirements, and networking capabilities. However, the “high performance” aspects of the instrumentation are still a high priority to the end user. These user requirements cause microscope manufacturers a dilemma in many instances. It is not always possible to provide the “new” requirements while still maintaining the high performance of the instruments, at a “reasonable” cost. An example is the large sample requirements in scanning electron microscopes. Large stages are inherently more prone to vibration than smaller stages, and therefore adversely affect resolution.