WorksheetsQuiz on Unit-II
Total questions: 10
Worksheet time: 3mins
Which method is commonly used to slice silicon ingots into wafers?
Laser cutting
Wire sawing
Plasma etching
Chemical etching
What is the main purpose of wafer edge rounding?
Reduce wafer thickness
Increase wafer conductivity
Prevent wafer cracks and chipping
Improve optical properties
In RCA cleaning, SC-1 solution primarily removes:
Organic contaminants and particles
Metal ions
Native oxide
Surface scratches
Which chemical mixture is used in SC-2 cleaning?
NH₄OH + H₂O₂ + H₂O
HCl + H₂O₂ + H₂O
HF + H₂O
HNO₃ + H₂O
Megasonic cleaning is preferred over ultrasonic cleaning because:
It is faster
It uses higher frequency and causes less wafer damage
It requires less water
It removes metal ions
The main objective of Chemical Mechanical Polishing (CMP) is to:
Increase wafer thickness
Remove metallic contaminants
Achieve a flat, smooth wafer surface
Etch patterns on wafer
Which of the following is NOT a component in CMP?
Polishing pad
Slurry
Downforce
Laser beam
Optical wafer inspection is mainly used to detect:
Subsurface voids
Surface scratches and particles
Crystalline defects
Wafer thickness variations
Infrared (IR) inspection is effective because silicon:
Reflects UV light
Is opaque to visible light but transparent to IR
Conducts heat well
Absorbs X-rays strongly
Which parameter is measured using surface profilometry?
Electrical resistivity
Flatness and roughness
Optical transparency
Thermal conductivity
