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Etch Overview for Microsystems Learning Module EEttcchh OOvveerrvviieeww ffoorr MMiiccrroossyysstteemmss Learning Module Map Knowledge Probe Etch Overview Activities (3) Final Assessments Instructor Guide www.scme-nm.org What is a SCO? A SCO is a "shareable-content object" or, what we like to call, a "self-contained object". The term SCO comes from the Shareable Content Object Reference Model (SCORM), first conceived by the Department of Defense in 1999 as part of the Advanced Distributed Learning Initiative (Gonzales, 2005; Advanced Distributed Learning, 2008). A SCO covers no more than 3 objectives that pertain to one specific topic (e.g., Material Safety Data Sheets or MEMS Applications). A SCO can be used by itself or with other SCOs with common or complementary objectives. We have grouped SCOs that support common objectives into a Learning Module. Learning Module Organization Each Learning Module (LM) contains at least one of the following three types of SCOs: Primary Knowledge (PK) - Each LM contains at least one PK which contains the basic information supporting the objectives. Most PKs have a supporting PowerPoint presentation. Activity (AC) – Each LM can contain one or more activities that provide interactive or hands-on learning that supports the objectives. Assessment (KP, FA, AA) – Each LM contains one or more assessments that determines the student's existing knowledge (Knowledge Probe (KP) or pretest) or knowledge gained relative to a particular AC, the PK or both. (Activity Assessment (AA), Final Assessment (FA)). Each SCO contains an Instructor Guide (IG) and Participant Guide (PG). Each SCO is self-contained; therefore any one SCO in the Learning Module can be used without the other SCOs, depending upon the needs of the student and the instructor. The instructor or student can pick and choose individual SCOs for select topics, lessons, units, courses or workshops. The graphic below illustrates this concept: SCME provides SCOs related to Microsystems (MEMS) Technology under many topics including Safety, Introduction to MEMS, Applications of MEMS, BioMEMS, and Fabrication of MEMS. Why SCOs? The study of microsystems incorporates many different STEM disciplines: physics, chemistry, biology, lab safety, and mathematics, just to name a few. The goal of SCME is to present MEMS-based lessons that utilize the concepts and principles of these disciplines. The use of SCOs offers an object-oriented way of presenting materials. Since MEMS education encompasses many subjects, SCME feels that by compartmentalizing materials into small units, it provides flexibility for instructors to introduce MEMS as an application of an existing discipline, to illustrate a concept or principle, or to incorporate MEMS-based education into new or existing curricula. Southwest Center for Microsystems Education (SCME) University of New Mexico MEMS Fabrication Topic Etch Overview for Microsystems Learning Module This booklet contains six (6) Sharable Content Object (SCOs): Knowledge Probe (KP) / pre-test Primary Knowledge Etch Terminology Activity Science of Thin Films Activity Bulk Micromachining: An Etch Process Activity Final Assessment The following Learning Module Map is a suggested outline on how to use this learning module. Target audiences: High School, Community College, University Support for this work was provided by the National Science Foundation's Advanced Technological Education (ATE) Program through Grants #DUE 0830384 and 0902411. Any opinions, findings and conclusions or recommendations expressed in this material are those of the authors and creators, and do not necessarily reflect the views of the National Science Foundation. Copyright © by the Southwest Center for Microsystems Education and The Regents of the University of New Mexico Southwest Center for Microsystems Education (SCME) 800 Bradbury Drive SE, Suite 235 Albuquerque, NM 87106-4346 Phone: 505-272-7150 Website: www.scme-nm.org Learning Module Map for Etch Overview Learning Module: Etch Overview for Microsystems Learning Module SCOs (6): Knowledge Probe (KP) Etch Overview for Microsystems Primary Knowledge (PK) Etch Terminology Activity Science of Thin Films Activity Anisotropic Etch Activity Final Assessment Databank Final Assessment – short answer (questions from databank) Final Assessment – multiple choice (questions from databank) Following is a suggested map on the implementation of this learning module. IMPORTANT STEPS KEY POINTS REASONS The KP helps to determine the participants’ current knowledge of the etch Have the participants complete process prior to starting Pre-test (Knowledge Probe) the Knowledge Probe in their the learning module. The booklet or online. outcome of the KP can be compared against the final assessment to determine the effectiveness of this learning module. It is something they are You want the participants familiar with, especially in to realize that they already Inquiry – nature. Examples – natural know what etch or etching Ask “What is etch or arches, widening river is – it’s nothing new. etching? Provide some banks, rotting pipe, erosion This unit will show how examples.” of any type, sandblasting, etch is used to make sculpturing. microdevices. Participants should read the An introduction into etch PK. is needed to help Unit Presentation: participants better Present the Etch Overview A PowerPoint presentation understand the etch for Microsystems PK can be downloaded from process. This will lead to scme-nm.org and presented more effective learning in to all participants. the related activities. Southwest Center for Microsystems Education (SCME) 2 of 4 Fab_Etch_LM_MAP_IG_051514 Etch Overview Learning Module Map This is a crossword puzzle of etch terms and their meanings. Provides participants with a This activity could be a Activity 1: review of the terminology homework or classroom Complete the “Etch associated with etch processes assignment. If you have access Terminology Activity”. and equipment. to the online course, participants can input their answers online. Activity 2: Rainbow Wafer Activity This activity can be used as a “stand-alone” activity or as part of this Etch Learning Module. It has its own PowerPoint presentation and the introductory material needed to complete this activity. This activity introduces the concepts of etch, oxidation and light interference. There is a SCME kit for this activity that can be ordered through scme-nm.org. Have the participants look at the Rainbow Wafer (from the SCME kits) from different This inquiry activity gets the angles. participants curious about the What colors do they see? Activity 2 Inquiry wafers, the different colors Do the colors of the layers they see, and how oxide change? thickness affects the colors on When do they change? the wafer. Why do they change? What are you seeing different colors? The introductory PowerPoint for this activity introduces the The presentation introduces Activity 2 Introduction: participants to three key the key concepts of the activity Introduce the “Science of concepts: etch rates, oxidation so that the participants gain a Thin Films Activity” with rates, and light interference. better understanding of the its presentation. data and information gathered The presentation can be during this activity. downloaded from scme-nm.org. Southwest Center for Microsystems Education (SCME) 3 of 4 Fab_Etch_LM_MAP_IG_051514 Etch Overview Learning Module Map This activity helps participants Correctly interpret oxidation to develop skills for charts. interpreting and developing graphs and tables. Estimate oxide thicknesses and Activity 2: complete Rainbow Wafer Participants learn the Complete the “Science of Calculations Worksheet. relationships between Thin Films Activity”. time and oxide thickness in (A kit is available through Calculate and graph etch rates oxidation processes, the SCME website and etch rates vs. oxide oxide thickness and etch (http://scme-nm.org) If thickness. rates, you do not have a kit, and oxide thickness and participants can still Explain several key concepts, color. complete this activity by such as why are several colors using the photo of a rainbow seen in oxide thicknesses when They also learn how wafer that is provided in the oxide is transparent? Why is SCO. light interference affects wet oxidation faster than dry what color they see on an oxidation? What is oxidation? oxidized wafer, What is etch rate and how can it wafers are oxidized, and be controlled? how wafers are etched. This activity uses hazardous chemicals and requires a fume This activity requires the Activity 3: hood for ventilation. mixing of sodium hydroxide Complete the “Bulk and water. Micromachining: An Etch Participants and instructors are Process Activity”. required to wear the proper This activity provides personal protective equipment. participants with There is a SCME kit for demonstration of bulk etch this activity that can be Participants observe the through the anisotropic etching ordered through scme- anisotropic etch of silicon using of silicon on the backside of a nm.org. sodium hydroxide (Drain MEMS pressure sensor die. Cleaner). Participants are evaluated on what they have learned about etch processes, the types of etch, etch rates, and the application of etch in MEMS Assessment: fabrication. Give the participants the final Complete one of the Etch assessment. Overview Assessment. Compare the results of this assessment with the results of the KP to determine the effectiveness of this learning module in teaching the etch process. Adapted from Graupp, P. & Wrona, R. (2006)
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