CMP and cleaning

What is the main reason wafer cleaning is considered important in semiconductor manufacturing?

  1. ABecause even slight contamination by particles or metals can cause shorts, opens and characteristic shifts that lower yield
  2. BTo make wafer colors uniform
  3. CTo make wafers lighter
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Answer: A. Because even slight contamination by particles or metals can cause shorts, opens and characteristic shifts that lower yield

In fine-featured LSIs, even particles tens of nanometers in size or trace metal and organic contamination can cause pattern defects, increased leakage and threshold voltage shifts. Cleaning to remove contamination before and after each step is therefore essential.

  • A. Correct. Even slight contamination causes defects.
  • B. It is not done to make colors uniform.
  • C. It is not done to change weight.
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More CMP and cleaning questions

  1. Which correctly describes how many times cleaning is performed across the whole LSI manufacturing flow?
  2. Which set correctly lists the kinds of surface contamination removed from wafers by cleaning?
  3. In processes such as multilevel wiring, what is the main reason the wafer surface must be planarized by CMP?
  4. Which correctly describes the basic configuration of a CMP tool?
  5. In Cu interconnect CMP, why is polishing generally divided into stages?