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Which metals or alloys amongst the following, do not reduce SiO2 and are found to have poor adhesion on SiO2 surfaces. A) W B) M0 C) Al D) TiN E) WSi2 Choose the correct answer from the options given below:

Which metals or alloys amongst the following, do not reduce SiO2 and are found to have poor adhesion on SiO2 surfaces. A) W B) M0 C) Al D) TiN E) WSi2 Choose the correct answer from the options given below: Correct Answer (A) and (B) only

Adhesive layer: It is a thin film of tungsten, niobium, chrome, or titanium. The gold layers are generally about 1 μm thick.

It is a tendency of dissimilar particles or surfaces to cling to one another.

Explanation:

  • Materials like Cr, Ni, Al, TiN, WSi2 have a good adhesion layer on SiO2.
  • Both Ni and Cr require high temperatures for melting and evaporation.
  • It is easy to thermally evaporate chromium using chrome-plated tungsten.
  • Generally, W and Mo do not reduce SiO2 and have poor adhesion on the SiO2 surface.

Option (4) correct.

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