Be a Scanning Probe Microscope

Build Materials (For each team)

Required Materials for classroom

• Box with item affixed to bottom (ruler, paper cup, brick, piece of fruit)
• Blindfold or cut a hole into the box so that students can fit their hand and a pencil inside, without seeing what is in the box. 

Required Materials for teams

• Paper
• Pen
• Pencil
• Access to the internet, optional

Design Challenge

You are a team of engineers given the challenge of using a pencil probe to “feel” two different objects inside a box (without seeing the objects). Next, you will draw what you “saw” and as a team agree on what the object in the box might be. Then, teams develop a detailed drawing showing the object you agreed on.

Criteria

• Must use a pencil to “feel” the objects.
• Must not be able to see the objects (either a blindfold or hole cut in the box to fit a hand and pencil)

Constraints

• Use only the materials provided.

Time Needed: One to two 45 minute sessions.

1. Break class into teams of 2-4.
2. Hand out the Be a Scanning Probe Microscope worksheet.
3. Discuss the topics in the Background Concepts Section. Ask students to consider how engineers measure the surface of things that are too small to see. If internet is available, share The Virtual Microscope (http://virtual.itg.uiuc.edu).
4. Review the Engineering Design Process, Design Challenge, Criteria, Constraints and Materials.
5. Provide each team with their materials.
6. Explain that students must use a pencil to “feel” two different objects inside a box (blindfolded). Next, they will draw what they “saw” and as a team agree on what the object in the box might be. Finally, teams develop a detailed drawing showing the object they agreed on.
7. Announce the amount of time they have to complete the activity (1 hour recommended).
8. Use a timer or an on-line stopwatch (count down feature) to ensure you keep on time. (www.online-stopwatch.com/full-screen-stopwatch). Give students regular “time checks” so they stay on task. If they are struggling, ask questions that will lead them to a solution quicker.
9. Instruct students to do the following:
   • Each student on the team takes turns using a pencil probe to determine the shape to identify objects in a box. You may either be blindfolded, or have a hole cut into a box so that your hand and the pencil can be inside without you seeing what is in the box.
   • Use just the tip of the pencil to examine the content or surface area of the bottom of the box.
   • In your mind, keep track of the height of the objects you sense, their shape, and overall size.
   • Next, draw what you “saw” on a piece of paper — you might want to consider a top and side view to help determine what is in the box.
   • When each student on the team has done the investigation, work together and share your drawings and opinions of what is in the box. Come up with a consensus as a team and develop a final drawing that includes estimated measurements of the object.
10. Teams present your ideas, drawings, and measurements to the class, and listen to the presentations of the other teams. They should compare how close their team was in determining the actual size and shape.
11. As a class, discuss the student reflection questions.
12. For more content on the topic, see the “Digging Deeper” section.

Optional Extension Activity

Have students mirror what they “feel” in the box with one hand, by drawing simultaneously on paper with the other hand.

Student Reflection (engineering notebook)

1. How accurate in terms of the shape was your team in identifying the object? What did you find in the box?
2. How accurate was your team in determining the actual size of the object in the box?
3. By what percentage was your size estimate off from the actual size of the object in the box?
4. Do you think that the amount of time you took to “see” inside the box with the probe impacted how accurate your findings were?
5. Did you think that working as a team made this project easier or harder? Why?

The lesson can be done in as little as 1 class period for older students. However, to help students from feeling rushed and to ensure student success (especially for younger students), split the lesson into two periods giving students more time to brainstorm, test ideas and finalize their design. Conduct the testing and debrief in the next class period.

What is Nanotechnology?

Imagine being able to observe the motion of a red blood cell as it moves through your vein. What would it be like to observe the sodium and chlorine atoms as they get close enough to actually transfer electrons and form a salt crystal or observe the vibration of molecules as the temperature rises in a pan of water? Because of tools or ‘scopes’ that have been developed and improved over the last few decades we can observe situations like many of the examples at the start of this paragraph. This ability to observe, measure and even manipulate materials at the molecular or atomic scale is called nanotechnology or nanoscience. If we have a nano “something” we have one billionth of that something. Scientists and engineers apply the nano prefix to many “somethings” including meters length), seconds (time), liters (volume) and grams (mass) to represent what is understandably a very small quantity. Most often nano is applied to the length scale and we measure and talk about nanometers (nm). Individual atoms are smaller than 1 nm in diameter, with it taking about 10 hydrogen atoms in a row to create a line 1 nm in length. Other atoms are larger than hydrogen but still have diameters less than a nanometer. A typical virus is about 100 nm in diameter and a bacterium is about 1000 nm head to tail. The tools that have allowed us to observe the previously invisible world of the nanoscale are the Atomic Force Microscope and the Scanning Electron Microscope.

How Big is Small?

It can be hard to visualize how small things are at the nanoscale. The following exercise can help you visualize how big small can be! Consider a bowling ball, a billiard ball, a tennis ball, a golf ball, a marble, and a pea. Think about the relative size of these items.

Scanning Electron Microscope

The scanning electron microscope is a special type of electron microscope that creates images of a sample surface by scanning it with a high energy beam of electrons in a raster scan pattern. In a raster scan, an image is cut up into a sequence of (usually horizontal) strips known as “scan lines.” The electrons interact with the atoms that make up the sample and produce signals that provide data about the surface’s shape, composition, and even whether it can conduct electricity. Many images taken with scanning electron microscopes may be viewed at www.dartmouth.edu/~emlab/gallery.

Atomic Force Microscopes

Imaging at the Nano Scale

In order to “see” what the surface of materials looks like at the nano scale, engineers have developed a range of devices and systems to explore how the surface of an object behaves. You can view lots of images at Dartmouth Electron Microscope Facility at www.dartmouth.edu/~emlab/gallery.

Atomic Force Microscopes

An Atomic Force Microscope is a special type of scanning probe microscope (SPM), that gathers information by using a probe to touch or move over the surface of a subject. The resolution is very high, at a fraction of a nanometer. The AFM was invented in 1982 at IBM and the first commercially available atomic force microscope was introduced in 1989. The AFM remains one of the most important tools for measuring and imaging anything at the nanoscale. It can quite accurately develop a three dimensional picture or topography of a sample, and has many applications. If you can imagine closing your eyes and using the tip of a pencil to figure out what object was in a box, you can imagine how this type of microscope works! One advantage of an Atomic Force Microscope is that it does not require special surroundings, and works well in an average environment, or even in liquid. This makes it possible to explore biology at the macromolecule level, or even review living organisms.

Internet Connections

• Atomic Force Microscopy
• The Virtual Microscope

Recommended Reading

• Scanning Probe Microscopy: The Lab on a Tip (Advanced Texts in Physics) (ISBN: 978-3642077371)
• Scanning Probe Microscopy (ISBN: 978-3662452394)

Writing Activity

Write an essay or a paragraph about how advances through nanotechnology have impacted the field of healthcare and medicine.

Alignment to Curriculum Frameworks

Note: Lesson plans in this series are aligned to one or more of the following sets of standards:

• S. Science Education Standards (http://www.nap.edu/catalog.php?record_id=4962)
• S. Next Generation Science Standards (http://www.nextgenscience.org/)
• International Technology Education Association’s Standards for Technological Literacy (http://www.iteea.org/TAA/PDFs/xstnd.pdf)
• S. National Council of Teachers of Mathematics’ Principles and Standards for School Mathematics (http://www.nctm.org/standards/content.aspx?id=16909)
• S. Common Core State Standards for Mathematics (http://www.corestandards.org/Math)
• Computer Science Teachers Association K-12 Computer Science Standards (http://csta.acm.org/Curriculum/sub/K12Standards.html)

National Science Education Standards Grades K-4 (ages 4-9)

CONTENT STANDARD A: Science as Inquiry

As a result of activities, all students should develop

• Abilities necessary to do scientific inquiry
• Understanding about scientific inquiry

CONTENT STANDARD B: Physical Science

As a result of the activities, all students should develop an understanding of

• Properties of objects and materials
• Position and motion of objects

CONTENT STANDARD E: Science and Technology

As a result of activities, all students should develop

• Abilities of technological design

CONTENT STANDARD F: Science in Personal and Social Perspectives

As a result of activities, all students should develop understanding of

• Science and technology in local challenges

CONTENT STANDARD G: History and Nature of Science

As a result of activities, all students should develop understanding of

• Science as a human endeavor

National Science Education Standards Grades 5-8 (ages 10-14)

CONTENT STANDARD A: Science as Inquiry

As a result of activities, all students should develop

• Abilities necessary to do scientific inquiry
• Understandings about scientific inquiry

CONTENT STANDARD B: Physical Science

As a result of their activities, all students should develop an understanding of

• Properties and changes of properties in matter

CONTENT STANDARD E: Science and Technology

As a result of activities in grades 5-8, all students should develop

• Abilities of technological design
• Understandings about science and technology

CONTENT STANDARD F: Science in Personal and Social Perspectives

As a result of activities, all students should develop understanding of

• Science and technology in society 

National Science Education Standards Grades 5-8 (ages 10-14)

CONTENT STANDARD G: History and Nature of Science

As a result of activities, all students should develop understanding of

• Science as a human endeavor
• Nature of science

National Science Education Standards Grades 9-12 (ages 14-18)

CONTENT STANDARD A: Science as Inquiry

As a result of activities, all students should develop

• Abilities necessary to do scientific inquiry
• Understandings about scientific inquiry

CONTENT STANDARD B: Physical Science

As a result of their activities, all students should develop understanding of

• Structure and properties of matter

CONTENT STANDARD E: Science and Technology

As a result of activities, all students should develop

• Abilities of technological design
• Understandings about science and technology

CONTENT STANDARD F: Science in Personal and Social Perspectives

As a result of activities, all students should develop understanding of

• Science and technology in local, national, and global challenges

CONTENT STANDARD G: History and Nature of Science

As a result of activities, all students should develop understanding of

• Science as a human endeavor
• Nature of scientific knowledge
• Historical perspectives

 Next Generation Science Standards Grades 2-5 (Ages 7-11)

Students who demonstrate understanding can:

Matter and its Interactions

• 5-PS1-1. Develop a model to describe that matter is made of particles too small to be seen.
• 5-PS1-3. Make observations and measurements to identify materials based on their properties. 

Standards for Technological Literacy – All Ages 

The Nature of Technology

• Standard 1: Students will develop an understanding of the characteristics and scope of technology.
• Standard 2: Students will develop an understanding of the core concepts of technology.
• Standard 3: Students will develop an understanding of the relationships among technologies and the connections between technology and other fields of study. 

Technology and Society

• Standard 4: Students will develop an understanding of the cultural, social, economic, and political effects of technology.
• Standard 6: Students will develop an understanding of the role of society in the development and use of technology.
• Standard 7: Students will develop an understanding of the influence of technology on history.

Abilities for a Technological World

Standard 13: Students will develop abilities to assess the impact of products and systems.

Try your hand at being a Scanning Probe Microscope!

Research Phase

Read the materials provided to you by your teacher. If you have access to the internet, also view the tutorial on this website: http://virtual.itg.uiuc.edu/training/AFM_tutorial/.   It will illustrate how the scanning probe microscopes work and help you understand how you will perform a similar task through this activity.

Try It Out!

Each student on your team will take turns using a pencil probe to determine the shape or identify of an object in a box.  You may either be blindfolded, or have a hole cut into a box so that your hand and the pencil can be inside without you seeing what is in the box.

Use just the tip of the pencil to examine the content or surface area of the bottom of the box.  In your mind, keep track of the height of the objects you sense, their shape, and overall size.

Next, draw what you “saw” on a piece of paper — you might want to consider a top and side view to help determine what is in the box.

When each student on the team has done the investigation, work together and share your drawings and opinions of what is in the box.  Come up with a consensus as a team and develop a final drawing that includes estimated measurements of the object

Presentation and Reflection Phase

Present your ideas, drawings, and measurements to the class, and listen to the presentations of the other teams.  See how close your team, or the other teams were, in determining the actual size and shape.  Then complete the reflection sheet.

Reflection

Complete the reflection questions below:

1. How accurate in terms of the shape was your team in identifying the object? What did you find in the box?

2. How accurate was your team in determining the actual size of the object in the box?

3. By what percentage was your size estimate off from the actual size of the object in the box?

4. Do you think that the amount of time you took to “see” inside the box with the probe impacted how accurate your findings were?

5. Did you think that working as a team made this project easier or harder? Why?