Explore topic-wise MCQs in Vlsi.

This section includes 11 Mcqs, each offering curated multiple-choice questions to sharpen your Vlsi knowledge and support exam preparation. Choose a topic below to get started.

1.

What is Piranha Solution?

A. It is a 3:1 to 5:1 mix of nitric acid and hydrogen peroxide that is used to develop the oxide layer on silicon substrate
B. It is a 3:1 to 5:1 mix of sulphuric acid and hydrofluoric acid that is used to clean silicon wafers removing organic and metal contaminants or photo resist after metal patterning
C. It is a 3:1 to 5:1 mix of sulphuric acid and hydrogen peroxide that is used to grow the oxide layer on the silicon
D. It is a 3:1 to 5:1 mix of sulphuric acid and hydrogen peroxide that is used to clean wafers of organic and metal contaminants or photo resist after metal patterning
Answer» E.
2.

Chemical Mechanical Polishing is used to ___________

A. Remove silicon oxide
B. Remove silicon nitride and pad oxide
C. Remove polysilicon gate layer
D. Reduce the size of the layout
Answer» C. Remove polysilicon gate layer
3.

The process by which Aluminium is grown over the entire wafer, also filling the contact cuts is?

A. Sputtering
B. Chemical vapour deposition
C. Epitaxial growth
D. Ion Implantation
Answer» B. Chemical vapour deposition
4.

To grow the polysilicon gate layer, which of the following chemical is used for chemical vapour deposition?

A. Silicon Nitride(Si<sub>3</sub>N<sub>4</sub>)
B. Silane gas(SiH<sub>4</sub>)
C. Silicon oxide
D. None of the mentioned
Answer» C. Silicon oxide
5.

The dopants are introduced in the active areas of silicon by using which process?

A. Diffusion process
B. Ion Implantation process
C. Chemical Vapour Deposition
D. Either Diffusion or Ion Implantation Process
Answer» E.
6.

The chemical used for shielding the active areas to achieve selective oxide growth is?

A. Silver Nitride
B. Silicon Nitride
C. Hydrofluoric acid
D. Polysilicon
Answer» C. Hydrofluoric acid
7.

The isolated active areas are created by technique known as ___________

A. Etched field-oxide isolation
B. Local Oxidation of Silicon
C. Etched field-oxide isolation or Local Oxidation of Silicon
D. None of the mentioned
Answer» D. None of the mentioned
8.

The ______ is used to reduce the resistivity of poly silicon.

A. Photo resist
B. Etching
C. Doping impurities
D. None of the mentioned
Answer» D. None of the mentioned
9.

Positive photo resists are used more than negative photo resists because ___________

A. Negative photo resists are more sensitive to light, but their photo lithographic resolution is not as high as that of the positive photo resists
B. Positive photo resists are more sensitive to light, but their photo lithographic resolution is not as high as that of the negative photo resists
C. Negative photo resists are less sensitive to light
D. Positive photo resists are less sensitive to light
Answer» B. Positive photo resists are more sensitive to light, but their photo lithographic resolution is not as high as that of the negative photo resists
10.

Silicon oxide is patterned on a substrate using ____________

A. Physical lithography
B. Photolithography
C. Chemical lithography
D. Mechanical lithography
Answer» C. Chemical lithography
11.

What is Lithography?

A. Process used to transfer a pattern to a layer on the chip
B. Process used to develop an oxidation layer on the chip
C. Process used to develop a metal layer on the chip
D. Process used to produce the chip
Answer» B. Process used to develop an oxidation layer on the chip