Reading Worksheet Class 3 Physics 585. Please complete and bring to class on Thursday. We will use it to guide discussion and you will hand it in later. Name______
Ohring Chapter 1: sections 1-6 to 1.8
1.6: Kinetics: now we talk about things which are out of equilibrium and now long does it take for changes to take place. This is really important for device lifetime & reliability studies etc.
1.6.1 First we are going to do continuum modeling.
1. What is Fick’s Law? Page 37
2. Note D. what are its units?
3. How does D depend on temperature?
4. Look at differential equation: 1-24. Have you ever seen anything like it?
5. What are the two kinds of BC that Ohring says are common in thin-film processes?
6. Try to understand the eqns. and figures
1.6.2 Second we are going to do atomistic modeling.
1. Can you understand the logic that gets you to eqn. 1-31 on page 41?
2. See what each of the terms is in the equation and how to relate them back to 1-23.
3. Understand what this force field thing is in 1.6.2.2.
4. Understand what the terms are in 1-36. What does * refer to?
5. Figure 1-19 is often associated with the name Eyring.
1.7 Nucleation is really, really important for thin film deposition. It applies in CVD (see problems 1-13) and all kinds of thin-film and surfaces structure and morphology questions. (Chapters 7, 9 & 8.)
1. What does * refer to on page 45?
2. Do you understand the logic that gives eqn. 1-42?
3. Do you understand figure 1-20? What is likely to happen to a nucleus smaller than r*?
1.8 Stress & Strain.
.1 Elastic
1. Ohring says that there are many material properties but he singles out mechanical behavior, why?
2. For this book, what are the units of stress (p. 47 bottom)?
- What symbol does he use for tensile stress? What for shear stress?
- What sign can tensile stress have?
3. What are the units and symbol for strain? p. 48.
- Can there be strain in a direction where there is not stress?
- Poisson ratio: what is its symbol? What are typical values?
4. Page 49. Equation 1-43, what name does Y have and what units might be used?
5. Equation 1-44, what name does mu have? How does it relate to other constants for isotropic materials?
6. Equation 1-45, what name does E have? What units does it have? How do these relate to Y?
1.8.2 Plastic.
7. What does the term irreversible have to do with explaining the difference between elastic and plastic behavior?
8. Which property associated with plastic behavior is most important for thin films?
9. Hardness testing: the last part of equation 1-46 has some problems. Is kg a unit of force?
10. Which is large Knoop or Vickers hardness?
11. Note some of the reasons hardness measurements can be flawed.
1.83 Stress in TF
12. Look at the features that distinguish the mechanical behavior of TF from that of bulk.
13. Also how temperature effects can cause stress.
Ask me what HW problems you must do for this chapter.
Chapter 2.5 & .6 pages 81-90
1. Study figure 2-12 (& similar in LH)
2. Note comment on page 82 (bottom) about which gauges are used for which pressures.
3. What is outgassing?
4. Of the 4 terms in 2-22 which are most significant in your system?
5. What are some of the ways people have sped up desorption? P. 85
6. If the pressure in my 60 liter vessel which is not being pumped goes up from 0.001 mtorr to 18 mtorr in 10 hrs., what is the apparent leak rate? Where does this fall on p 85 table?
2.5.4
7. Understand the types of gauges and analyzers discussed in this section and their pressure ranges.
8. For next time I will give your reading from LH that will help you understand more about the Gauges, their corrections and characteristics.
Ask me what HW problems you must do for this chapter.