Reading Worksheet Class 7 Physics 585. Please complete and bring to class on______.
We will use it to guide discussion and you will hand it in later. Name______

Your QUESTIONS are important. WRITE down at least two you have. Put star by the items of greatest misunderstanding.

Class 7: Ohring Chapter 4: sections 4.5 to end (pp. 170-201.) Look at figure 4-19 several times during your reading to tether the info being thrown at you.

4.5.1 Ohring looks at this chapter as being science of ion-surface interactions.

  1. Look at figure 4-9 twice. Once right now and again as you finish the chapter.
  2. Figure 4-10 is schematic in nature. Understand reason for all three regions.

4.5.2

  1. Which class of ions is most likely to reflect?
  2. High-energy, massive, normal-incidence ions? Or something else?
  3. Why?
  4. Figure 11. C. is historical. People thought maybe sputtering was atomic scale e-beam. (Thermal spike leading to evaporation.) But what is the mechanism really?
  5. Why is there an energy threshold for sputtering?
  1. What is the basic rule? Why?
  2. What is gamma?

Sputter yield. Things to think about include:

What are the minimum and maximum S you can find in the text?

  1. Table 4-2 has two kinds of facts. Sputter yield and threshold.
  1. What is the minimum and maximum S in table?
  1. How many sputtering formula can you find in text?
  2. What are the factors in the various sputter formulae?
  1. Low-energy sputter?
  2. High-energy sputtering?
  3. Linear collision region?
  1. How good is the comparison with experiment?
  2. Alloys (page 180-1): How many monolayers of target are consumed to achieve steady-state composition?
  3. A potpourri of sputtering results 7 effects
  1. What two are most interesting to you?
  1. What angle gives largest sputter yield?

4.6 Modification of growing films

  1. 4.6.1 Perhaps read it twice but don’t worry if you can’t capture it.
  2. 4.6.2 Thermal spikes- read last sentence first and last.

4.6.3 contains the major issues.

  1. Topography.
  1. What are the new words/terms?
  2. Draw a picture that captures some of the important ideas.
  1. Crystallography and texture.
  1. Do you understand what texture means?
  2. Do you understand fig. 4-16?
  1. Grain structure: be prepared to communicate your understanding of fig. 4-17.
  2. Defects and Stress. Be prepared to communicate your understanding of these.
  3. Compositional modification of surfaces: Be prepared to communicate your understanding of this.
  4. Ion implanting and other high-energy processes.
    Ask yourself what are the conditions that lead to each of the four processes.
    Is it different energies, doses or some other property such as the crystallinity & orientation of the substrate?
  5. Implantation 191-93
  1. What is symbol for stopping power?
  2. Do you understand 4-43 in light of assigned HW?
  3. What is Rp?
  4. What is straggling and what is symbol?
  1. Channeling has nothing to do with psychics
  2. Where is ion-beam mixing mostly likely to be important for you?
  1. What is the basic rule of dose in determining if amorphization is going to happen?

4.7 Conclusion

  1. Look at Fig 4-19 (again).
  2. Do you see an answer to an essay question here?
  3. Read last of section to see Ohring’s answer.
  4. Table 4-3 compares evaporation vs. sputtering for thin films.
  5. It could provide the answers for three potential essay questions.
  6. Read over it looking for the answer to such questions.
  7. What is one such question?
  1. How would you answer it?