3.155J/6.152 J Fall2003 MOSCAP Pre-Lab Questions 1. What contaminants does the rCa clean remove? What is the purpose of the HF dip in the rca clean? 2. Why is dry oxidation used to grow the gate oxide? 3. From the oxide growth chart in the Appendix, predict the gate oxide thickness after the oxidation 4. From the oxide color chart in the Appendix, what color would one expect the gate oxide to appear 5. What are the advantages of using polysilicon rather than aluminum for the gate electrode? 6. What is the by-product of the polysilicon deposition? What controls the deposition rate (transfer of SiH4, reaction at the surface of the substrate, or removal of the by-product)? 7. Sketch a cross section of the wafer after this lab session3.155J / 6.152J Fall 2003 MOSCAP 3 Pre-Lab Questions: 1. What contaminants does the RCA clean remove? What is the purpose of the HF dip in the RCA clean? 2. Why is dry oxidation used to grow the gate oxide? 3. From the oxide growth chart in the Appendix, predict the gate oxide thickness after the oxidation. 4. From the oxide color chart in the Appendix, what color would one expect the gate oxide to appear? 5. What are the advantages of using polysilicon rather than aluminum for the gate electrode? 6. What is the by-product of the polysilicon deposition? What controls the deposition rate (transfer of SiH4, reaction at the surface of the substrate, or removal of the by-product)? 7. Sketch a cross section of the wafer after this lab session