TEM Studies of Low Energy Argon and Iodine Ion Milling Phenomena in Compound Semiconductors

1985 ◽  
Vol 62 ◽  
Author(s):  
A. G. Cullis ◽  
N. G. Chew ◽  
J. L. Hutchison
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Compound Semiconductors ◽  
Low Energy ◽  
Specimen Preparation ◽  
Dislocation Loops ◽  
Ion Milling ◽  
Thin Specimen ◽  
Transmission Electron ◽  
Dense Arrays

ABSTRACTThe nature of disorder produced by low energy Ar+ and I+ ions (and atoms) in the III–V compound semiconductors InP and InSb, and in the II–VI semiconductors CdTe, ZnS and ZnSe has been studied in detail by conventional and high resolution transmission electron microscopy. It is demonstrated that for Ar+ ion bombardment the disorder in the III–V compounds comprises segregated indium islands which accumulate on the machined surfaces, while for the II–VI compounds the disorder consists of dense arrays (∼1011 cm−2) of small dislocation loops near to each bombarded surface. When Ar+ ions or Ar atoms are used for thin specimen preparation by milling prior to electron microscopy, the disorder produced gives contrast which seriously obscures images and so complicates their interpretation. This problem concerning the presence of artifactual defects can be greatly reduced or even eliminated by the use of reactive I+ ion milling for the final thinning of specimens.

Transmission Electron Microscopy of Semiconductor Based Products

1998 ◽  
Vol 523 ◽  
Author(s):  
John Mardinly ◽  
David W. Susnitzky
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ion Beam ◽  
Semiconductor Industry ◽  
Size Reduction ◽  
Specimen Preparation ◽  
Specimen Thickness ◽  
Ion Milling ◽  
Feature Size ◽  
Transmission Electron

AbstractThe demand for increasingly higher performance semiconductor products has stimulated the semiconductor industry to respond by producing devices with increasingly complex circuitry, more transistors in less space, more layers of metal, dielectric and interconnects, more interfaces, and a manufacturing process with nearly 1,000 steps. As all device features are shrunk in the quest for higher performance, the role of Transmission Electron Microscopy as a characterization tool takes on a continually increasing importance over older, lower-resolution characterization tools, such as SEM. The Ångstrom scale imaging resolution and nanometer scale chemical analysis and diffraction resolution provided by modem TEM's are particularly well suited for solving materials problems encountered during research, development, production engineering, reliability testing, and failure analysis. A critical enabling technology for the application of TEM to semiconductor based products as the feature size shrinks below a quarter micron is advances in specimen preparation. The traditional 1,000Å thick specimen will be unsatisfactory in a growing number of applications. It can be shown using a simple geometrical model, that the thickness of TEM specimens must shrink as the square root of the feature size reduction. Moreover, the center-targeting of these specimens must improve so that the centertargeting error shrinks linearly with the feature size reduction. To meet these challenges, control of the specimen preparation process will require a new generation of polishing and ion milling tools that make use of high resolution imaging to control the ion milling process. In addition, as the TEM specimen thickness shrinks, the thickness of surface amorphization produced must also be reduced. Gallium focused ion beam systems can produce hundreds of Ångstroms of amorphised surface silicon, an amount which can consume an entire thin specimen. This limitation to FIB milling requires a method of removal of amorphised material that leaves no artifact in the remaining material.

A temperature-jump technique for time-resolved cryo-transmission Electron Microscopy

1989 ◽  
Vol 47 ◽  
pp. 742-743
Author(s):  
H. Chestnut ◽  
D. P. Siegel ◽  
J. L. Burns ◽  
Y. Talmon
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Liquid Crystalline ◽  
Temperature Jump ◽  
Specimen Preparation ◽  
Thin Specimen ◽  
Time Resolved ◽  
Sequence Of Events ◽  
Transmission Electron ◽  
Focused Beam

Transmission electron microscopy of rapidly-frozen, hydrated specimens (cryo-TEM) is a powerful way of examining labile microstructures. This technique avoids some artifacts associated with conventional preparative methods. Use of a controlled environment vitrification system (CEVS) for specimen preparation reduces the risk of unwanted sample changes due to evaporation, and permits the examination of specimens vitrified from a defined temperature. Studies of dynamic processes with time resolution on the order of seconds, in which the process was initiated by changes in sample pH, have been conducted. We now report the development of an optical method for increasing specimen temperature immediately before vitrification. Using our method, processes that are regulated by temperature can be initiated in less than 500 msec on the specimen grid. The ensuing events can then be captured by plunge-freezing within an additional 200 msec.Dimyristoylphosphatidylcholine (DMPC) liposomes, produced by extrusion, were used as test specimens. DMPC undergoes a gel/liquid crystalline transition at 24°C, inducing a change in liposome morphology from polyhedral to spherical. Five-μl aliquots of DMPC dispersions were placed on holey-carbon-filmed copper grids mounted in the CEVS environmental chamber, and maintained at 6-8°C and 80% relative humidity. Immediately before the temperature jump most of the sample was blotted away with filter paper, leaving a thin specimen film on the grid. Upon pressing the trigger, an electronic control circuit generated this timed sequence of events. First, a solenoid-activated shutter was opened to heat the specimen by exposing it for a variable time to the focused beam of a 75W Xenon arc lamp. Simultaneously, a solenoid-activated cryogen shutter in the bottom of the CEVS was opened. Next, the lamp shutter was closed after the desired heating interval. Finally, a solenoid-activated cable release was used to trigger a spring-loaded plunger in the CEVS, propelling the sample into a reservoir of liquid ethane. Vitrified samples were subsequently transferred to a Zeiss EM902 TEM, operated in zero-loss brightfield mode, for examination at −163°C.

Preparation of Electropolished Transverse Sections of Thin Aluminum Sheet for Transmission Electron Microscopy

1987 ◽  
Vol 115 ◽  
Author(s):  
Steve Smith
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Transverse Section ◽  
Aluminum Sheet ◽  
Specimen Preparation ◽  
Ion Milling ◽  
Transmission Electron ◽  
Thin Aluminum ◽  
Time Required

ABSTRACTThe preparation of transverse section TEM foils from thin (0.2 mm to 1.5 mm) aluminum sheet would usually be accomplished by a combination of dimpling and ion milling. Both of these techniques are time consuming. A technique has been developed which allows these transverse section foils to be prepared by electropolishing, which greatly reduces the time required for specimen preparation. This technique also produces far more thin area for examination than a comparable foil which has been dimpled and ion milled, and eliminates artifacts produced by ion milling.

New Technique for Successful Thermal Barrier Coating Specimen Preparation for Transmission Electron Microscopy

2000 ◽  
Vol 6 (3) ◽  
pp. 231-236
Author(s):  
M.R. Brickey ◽  
J.L. Lee
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Thermally Grown Oxide ◽  
Thermal Barrier ◽  
Specimen Preparation ◽  
Ion Milling ◽  
New Approach ◽  
Barrier Coating ◽  
Transmission Electron ◽  
Thermal Histories

Abstract Reliability of thermal barrier coatings (TBC) hinges on the adhesion of a thermally grown oxide scale to an insulative ceramic topcoat and an underlying metallic bondcoat. The width of the scale and its interfaces makes transmission electron microscopy (TEM) an appropriate tool for its analysis. However, specimen preparation has proven to be a challenging obstacle leading to a dearth of TEM research on TBCs. A new approach to cross-section TBC TEM specimen preparation is described. The principal advantages of this technique are reproducibility, reduced specimen damage, and time savings resulting from decreased ion milling. This technique has been successfully applied to numerous TBC specimens with various thermal histories.

Direct Observation by Transmission Electron Microscopy of the Early Stages of Growth of Superconducting Thin Films

1989 ◽  
Vol 169 ◽  
Author(s):  
M. Grant Norton ◽  
Lisa A. Tietz ◽  
Scott R. Summerfelt ◽  
C. Barry Carter
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Substrate Surface ◽  
Critical Role ◽  
Specimen Preparation ◽  
Superconducting Thin Films ◽  
Ion Milling ◽  
Early Stages ◽  
Transmission Electron

AbstractThe fabrication of high quality thin films often depends on the early stages of the growth process during which epitaxy is established. The substrate surface structure generally plays a critical role at this stage. Many observations of the high‐Tc superconductor film‐substrate interface structure and chemistry have been made by transmission electron microscopy (TEM) of cross‐section samples. Ion‐milling induced damage, however, can be severe in these specimens. In the present study, the early stages of the growth of high Tc superconducting thin films of YBa2Cu3O7δ have been studied by TEM using a technique which requires no post‐deposition specimen preparation.

High-Quality Sample Preparation by Low kV FIB Thinning for Analytical TEM Measurements

2007 ◽  
Vol 13 (2) ◽  
pp. 80-86 ◽  
Author(s):  
Sara Bals ◽  
Wim Tirry ◽  
Remco Geurts ◽  
Zhiqing Yang ◽  
Dominique Schryvers
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Beam Specimen ◽  
Specimen Preparation ◽  
Ion Milling ◽  
High Quality ◽  
Transmission Electron ◽  
Quantitative Manner

Focused ion beam specimen preparation has been used for NiTi samples and SrTiO3/SrRuO3 multilayers with prevention of surface amorphization and Ga implantation by a 2-kV cleaning procedure. Transmission electron microscopy techniques show that the samples are of high quality with a controlled thickness over large scales. Furthermore, preferential thinning effects in multicompounds are avoided, which is important when analytical transmission electron microscopy measurements need to be interpreted in a quantitative manner. The results are compared to similar measurements acquired for samples obtained using conventional preparation techniques such as electropolishing for alloys and ion milling for oxides.

scholarly journals Investigation of III–V Nanowires by Plan-View Transmission Electron Microscopy: InN Case Study

2014 ◽  
Vol 20 (5) ◽  
pp. 1471-1478 ◽  
Author(s):  
Esperanza Luna ◽  
Javier Grandal ◽  
Eva Gallardo ◽  
José M. Calleja ◽  
Miguel Á. Sánchez-García ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Strain Relaxation ◽  
Milling Process ◽  
Specimen Preparation ◽  
Shell Layer ◽  
Ion Milling ◽  
Cross Sectional ◽  
Plan View ◽  
Transmission Electron

AbstractWe discuss observations of InN nanowires (NWs) by plan-view high-resolution transmission electron microscopy (TEM). The main difficulties arise from suitable methods available for plan-view specimen preparation. We explore different approaches and find that the best results are obtained using a refined preparation method based on the conventional procedure for plan-view TEM of thin films, specifically modified for the NW morphology. The fundamental aspects of such a preparation are the initial mechanical stabilization of the NWs and the minimization of the ion-milling process after dimpling the samples until perforation. The combined analysis by plan-view and cross-sectional TEM of the NWs allows determination of the degree of strain relaxation and reveals the formation of an unintentional shell layer (2–3-nm thick) around the InN NWs. The shell layer is composed of bcc In2O3 nanocrystals with a preferred orientation with respect to the wurtzite InN: In2O3 [111] || InN [0001] and In2O3 <110> || InN< $$ 11\bar 20 $$ >.

Sign in / Sign up

Export Citation Format

Share Document