MSE 421/521 INTRODUCTION TO ELECTRON MICROSCOPY

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1 MSE 421/521 INTRODUCTION TO ELECTRON MICROSCOPY Brief syllabus: The theory and practice of scanning electron microscopy (SEM) and transmission electron microscopy (TEM), including electron optics, contrast mechanisms, diffraction theory, chemical analysis techniques, and sample preparation. Applications of SEM and TEM in materials science and engineering will be covered. Aims: This course will introduce students to the use of a Hitachi S-3400N VP SEM and a JEOL 2100 HR TEM as well as the basic techniques for microstructural characterization, chemical analysis, crystal structure determination, and defect analysis in crystals. Course value: 3 cu Semester: 2 Pre-requisites: MSE 305/505 Lectures: 29 Tutorials: 5 Overlap courses: MSE 305/505, PHYS 423 Limits on number: N/A Examinations/Coursework Marks: MSE 421 MSE 521 Homework 35% (5% x7) 28% (4% x 7) Quizzes 33% (11% x3) 27% (9% x 3) Report N/A 15% Participation 5% 5% Final Exam 27% 25% Text: Brandon & Kaplan, Microstructural Characterization of Materials 2 nd ed., Wiley, Chichester, A+ 97% Course organizer: Dr. A 90% MEC 302H A- 87% Teaching Assistant: B+ 85% B 78% Time: Mon & Wed, 1:40 2:55 B- 75% D+ 55% C+ 71% D 45% Location: MEC 307 C 63% D- 40% C- 60% F 0% Microscopy with Light and Electrons: Methods of image formation, optical microscopy, magnification, resolution, depth of field, lens aberrations, electrons vs light Interaction of Electrons with Matter: Electrons, electron generation, magnetic lenses, scattering, secondary effects, electron microscopes Electron Diffraction: geometry of diffraction, spot patterns, reciprocal lattice, other types of diffraction Transmission Electron Microscope: Instrument, contrast mechanisms, HVEM, STEM, sample preparation Syllabus Scanning Electron Microscope: Instrument, optics, performance, resolution, topographical images, compositional images, crystallographic information, other signals, sample preparation, low-voltage microscopy, ESEM Chemical Analysis: generation of x-rays, x- ray detection, EDS, WDS, quantitative analysis, EELS Other Techniques: scanning tunneling microscopy, AFM, FIM, holography, tomography, RHEED & LEED, atom probe FIM, SIMS, Auger spectroscopy, XPS, confocal microscopy, Raman and IR spectroscopy.

2 Homework Homework is a "practical' aspect of the course. Students may work on homework problems during the lab while instruments are occupied by other students. Seven homework assignments will be assigned throughout the semester. Rules for Homework and Quizzes 1. Show ALL your work. Do NOT submit electronic results or results in spreadsheet form unless otherwise instructed. 2. Physical quantities have a numerical value and a unit. Numerical results without an SI unit will not be graded (exceptions are dimensionless quantities). 3. Mark formal and numerical results clearly by double-underlining or boxing. 4. Diagrams and drawings must be labeled. Axes should have names and units. Diagrams without sufficient labeling will not be marked. 5. Do not use red ink in drawings or diagrams. 6. Use of textbooks, lecture notes, and calculators is allowed for homework. 7. All homework is to be done individually. 8. Homework sheets will be marked and returned within one week of their due date. Reading Assignments A reading assignment is given each week. The content will have a significant overlap with the lectures but will also contain additional material to compliment the lectures. Quizzes Four quizzes will be scheduled throughout the semester. Apart from the first one, which will only cover the content of the course syllabus, all quizzes will generally cover the content of the reading assignment due that day, but may also require knowledge of previous reading assignments. One quiz may be dropped from the final quiz mark. Late Homework or Missing Quizzes Late homework assignments will only be accepted with a valid note from a doctor clearly indicating the name of the patient, the symptoms/diagnosis, and dates affected. The note must be delivered to Dr. Ubic as soon as possible and, in any event, within one week of the original due date for the assignment. In other circumstances, penalty points will be deducted by applying the following formula to the graded assignment: (1 - n/7)m, where n is the number of days late and M is the un-penalised grade for the work. Likewise, quizzes cannot be taken late without a doctor's note and, in any event, never later than one week after the original quiz date. Final Exam There will be a comprehensive final exam for this course on 7 May 2012, 3:30 5:30. It will cover the entire content of the course. Academic Honesty The BSU policy on academic honesty is covered on p. 22 of the undergraduate catalog: and p of the graduate catalog:

3 Participation Credit will be awarded for attendance and participation during class and for submitting all required coursework. Marks will also be given for participation in the Just a Minute exercise. In addition, extra credit will be given to the whole class if a 100% response rate is achieved in the end-of-term course evaluations. Presentation Just a Minute On 30 April 2012, an exercise will be played like a panel game in which students will be challenged to speak on a subject for one minute without hesitation, repetition, or deviation. Subjects relevant to the content of MSE 421/521 will be chosen by the instructor and other members of the class. Students score a point for making a correct challenge against whomever is speaking, while the speaker wins a point if the challenge is deemed incorrect by the instructor; however, if a particularly insightful, obscure, or witty remark sufficiently enlightens or amuses the class, even if not a correct challenge, both the challenger and speaker may gain a point, at the instructor s discretion. A student who makes a correct challenge takes over the subject for the remainder of the minute, or until he or she is correctly challenged. The person speaking when the 60 seconds expires also scores a point. An extra point is awarded when a student speaks for the entire minute without being challenged. For the purposes of this exercise: "Hesitation" can be a momentary pause before resumption of the subject, tripping over one's words, pausing for dramatic/comic effect, or waiting during laughter or applause. "Repetition" means the repeating of any word or phrase, although challenges based upon very common words such as "and" will generally be rejected except in extreme cases. Words contained in the given subject are exempt unless repeated many times in quick succession. "Deviation" means straying from the subject but can also be interpreted as deviation from the English language as we know it, deviation from grammar as we understand it, deviating from the truth, or deviation from logic, although leaps into the surreal may sometimes be allowed. Points scored during Just a Minute will be included in the course participation mark. Office Hours Mondays 3:00 4:00 Tuesdays 9:00-11:00 MEC 302H or as indicated on whiteboard

4 Physical constants Symbol Value Units Speed of light in vacuum c ms -1 Planck s constant h Js Charge on an electron e C Rest mass of an electron m o kg Avogadro s number N A mol -1 Other Symbols λ ν E m v V wavelength frequency energy mass velocity potential difference Units of convenience (not SI but sometimes used) Hz ev Å Hertz = cycles per second, same as s 1 but easier to say electron volts = energy in Joules divided by the charge on an electron, often used with electron beam instruments as it gives numbers that are easier to handle, e.g., J = 1.5 kev angstrom units = m, i.e nm often used as it is similar to atomic dimensions, e.g., radius of gold atom = Å ( nm)

5 Acronyms Acronym Meaning: Associated with: AES Auger electron spectroscopy Specialised surface analysis technique BEI Backscattered electron imaging Image mode in SEM CA Condenser aperture Microscopy EBSD Electron backscatter diffraction Crystallographic information in SEM ECP Electron channelling pattern Crystallographic information in SEM EDS Energy dispersive x-ray spectroscopy Chemical analysis mode in EMs EELS Electron energy loss spectroscopy Chemical analysis mode in TEM EM Electron microscopy Microscopy techniques EPMA Electron probe microanalysis Specialised SEM ESCA Electron spectroscopy for chemical analysis Specialised surface analysis (=XPS) FEG Field emission (electron) gun Type of electron source in HR EM FIB Focused ion beam Electron microscopes (spec. prep.) HR High resolution In EM, i.e., HRSEM, HRTEM OA Objective aperture Microscopy OM Optical microscopy Microscopy technique SAD Selected area diffraction Type of diffraction pattern in TEM SAM Scanning Auger microscopy Specialised surface analysis technique SEI Secondary electron image Image mode in SEM SEM Scanning electron microscope Electron microscope STEM Scanning transmission electron microscope Electron microscope TEM Transmission electron microscope Electron microscope WDS Wavelength dispersive spectroscopy (of X-rays) Chemical analysis mode in SEMs WEDS Windowless EDS Chemical analysis mode in EMs XPS X-ray photoelectron spectroscopy Specialised surface analysis (=ESCA) XRD X-ray diffraction Crystallographic analysis technique ZAF Atomic number, absorption and fluorescence Correction for quantitative EDS, WDS

6 MSE Report Students registered for MSE 521 will additionally be expected to complete a written report on the use of electron microscopy in their project work. The report should be formatted like a standard scientific manuscript as per the instructions for Materials Research Bulletin: The page limit, excluding figures, references, and appendices is 5. It should be written in 12- point Times New Roman font with 1.5 line spacing and single-sided. The report is due by 4:00 on Wednesday 25 April Publications and Presentations Beyond MSE 421 / 521 All presentations or publications which include data from the JEOL 2100 TEM must include an acknowledgement to the effect that the work was supported by the National Science Foundation Major Research Instrumentation Program, Award No All presentations or publications which include data from the Hitachi S-3400N SEM must include the following acknowledgement and disclaimer: Acknowledgment: This material is based upon work supported by the Department of Energy [National Nuclear Security Administration] under Award Number DE-NE Disclaimer: This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Learning Outcomes: By the end of this course, students should be able to: 1. Demonstrate an understanding of the fundamentals of optical microscopes, including magnification, resolution, aberrations, and depth of field. 2. Describe generation of electrons and their interactions with matter. 3. Index electron diffraction patterns including spot patterns, Kikuchi patterns, and EBSD patterns and explain variations in intensity in terms of structure factor. 4. Explain the operating principles and construction of both SEMs and TEMs. 5. Explain the generation of x-rays in a specimen and compare/contrast various chemical analysis techniques, including EDS, WDS, Auger, and EELS.

7 Marking Scheme for MSE 521 Written Report Name of Student: Examiner: Criterion Mark (%)/Comments Organisation and Structure: 20% of Total Mark % Are section headings listed and page numbers given? Is the report set out in a sensible order? Does the abstract adequately convey the aims, outcomes and conclusions of the project? Is the report easy to follow? Are the references cited in a consistent format? Introduction/Literature Survey: 20% of Total Mark % Does the literature survey progress logically from the general background to the specific subject matter of the project? Is sufficient information given on how SEM/TEM can advance the project? Are different methods described? Experimental Details: 20% of Total Mark % Are the sample preparation details given sufficient to allow someone else to repeat this work? Are they appropriate? Are the models, manufacturers and locations of manufacturers of equipment given? Are the grades, purities and sources of reagents cited? Results: 25% of Total Mark % Are the results clearly set out? Are sufficient results presented? Have they been fully analysed? Outlook: 15% of Total Mark % Is there a critical evaluation of the use of electron microscopy for this project? Are the next steps in the project discussed? TOTAL %

8 EVACUATION PROCEDURE EVACUATING YOUR BUILDING OR WORK AREA: When ordered to evacuate or when alarms are activated, always leave immediately. Exit quickly and calmly using nearest emergency escape routes and marked exits and proceed to safe assembly locations as identified in the evacuation map for your classroom. Do not use elevators. Be alert for trapped, injured or other persons needing assistance. See EVACUATION ASSISTANCE below. Do not return to an evacuated building unless directed to do so by authorities. EVACUATION ASSISTANCE Be alert for mobility-impaired, trapped, injured or other persons needing assistance. Help those persons requiring assistance to get to a designated Evacuation Assistance Area if it is safe to do so. These areas are identified in COLLEGE OF ENGINEERING BUILDING EVACUATION AND SAFETY EQUIPMENT MAPS on following pages. First responders will tend to those in evacuation assistance areas as soon as possible after arriving. Transporting of individuals requiring evacuation assistance up or down stairwells must be avoided unless imminent life-threatening conditions exist. Notify emergency personnel immediately upon their arrival of the exact location of any injured or trapped persons, those waiting in designated Evacuation Assistance Areas and any others who may be anywhere in the building. MEETING FIRST RESPONDERS If first responders are summoned and you have specific knowledge relating to the emergency, meet with them upon arrival. The first responders will typically stop at the following locations: Engineering and Technology Building- University Dr. Micron Engineering Center- Manitou Ave. Harry Morrison Civil Engineering Building- Euclid Ave. Construction Management Lab Bldgs- Belmont St. or Manitou Ave. The College of Engineering Emergency Response Guide can be found on-line at:

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