薄膜材料复习题.doc

1. Please depict the effects of ion bambardment in the processes of film growth and plasma etching.

2. Please summarize the deposition methods, properties, and application of diamond films.
3. What is the distinction between PVD from CVD?

4. Please describe the principle of magnetron sputtering according to the following figure.

5. Please explain the working principles of Rotary vane pump, Diffusion pump, and Cryopump.

6．(a) Please quantitatively discuss why a negative self-bias emerges on an electrode in the RF discharge plasma, (Assuming Townsend secondary-electron coefficient γe is 0.1; electron velocity ve=9.5×107 cm/s, ion velocity vi=5.2×104 cm/s); (b) Deduce the relationship formula between the self-bias value and electrode size. (Assuming the same current density jA=jB, jA=4ε0/9dsA2×(2q/m)1/2VA3/2, jB=4ε0/9dsB2×(2q/m)1/2VB3/2)

7. (1) What special x-ray diffraction condition is required for characterizing thin film materials comparing with bulk materials? Why? (2) What are the origins causing stress in thin films?

8．Please describe the fundamental sequential steps in CVD process.

9. Please calculate the thickness uniformity of deposition on the plate shown in the following figure (the thickness ratio between the edge and center of the plate) for point source and surface source, respectively.(3-29)

10. The following figure shows the changes of lattice constants, grain size, and dislocation density of grown thin films with bombarding energy, please explain the reasons of the changing trend? (4-86)

11. Please discuss how substrate temperature and concentration of source gases influence thin film structure during CVD process? (6-65)

12. What’s the origin of internal stress in thin films? How to evaluate internal stress of thin films by XRD?

13. Please deduce the formula calculating mean free path. (2-14)

14．What are molecular flow, viscous flow, and turbulent flow and their distinguishing criteria? (2-22)

15. (a) Please derive the calculation formula of impurity concentration originated from the residual gases during thin film evaporation process. (b) An Al film was deposited at a rate of about 1μm/min in vacuum at 25°C, and it was estimated that the oxygen content of the film was 10-3. What was the partial pressure of oxygen in the system? (Assuming the density of Al films to be 2.7g/cm3)

16. In the following horizontal reactor for epitaxially growing Si films the susceptor is tilted. Why?

17. Please summarize the deposition methods and application of metal films.

18. In the presence of ion bombardment the hBN (tBN) crystals are oriented with the c-axis parallel to the substrate surface as shown in the following figure, why?