Question

Which of the following is true about the layer of dielectric that is deposited on top of the wafer after metallization is complete? Select one:

a. It is also called an "topglass layer"
b. Holes must be etched through this layer in regularly spaced intervals, to allow for stress relief due to thermal expansion
c. Silicon dioxide is often used for this layer, since it is very tough and makes an excellent barrier to most contaminants
d. It is used to seal and passivate the metallization, to protect the rest of the chip from the copper metal which is a contaminant in silicon
e. None of these

Answer 1

The true statement about the dielectric layer is that silicone dioxide is often used for its toughness and capability as a barrier against contaminants.

Step-by-step explanation:

The correct option regarding the layer of dielectric that is deposited on top of the wafer after metallization is complete is: c. Silicon dioxide is often used for this layer, since it is very tough and makes an excellent barrier to most contaminants. The dielectric layer, often silicon dioxide, is used to seal and passivate the metallization.

It also serves to protect the rest of the chip from potential contamination. Passivation is crucial as it involves the formation of a protective oxide layer that prevents further corrosion or reaction. In silicon's case, the passivation layer is primarily silicon dioxide (SiO₂), which, while is soluble in hot aqueous base, provides robust protection under normal conditions.