CMP and cleaning
Which correctly describes CMP (chemical mechanical polishing)?
- AIt planarizes the surface by combining the chemical action of a slurry with mechanical polishing by a pad
- BIt planarizes the surface by etching it with ions from a plasma
- CIt planarizes the surface by melting it at high temperature
Show answer and explanation
Answer: A. It planarizes the surface by combining the chemical action of a slurry with mechanical polishing by a pad
In CMP, the wafer is pressed against a rotating polishing pad while a slurry containing abrasive particles and chemicals is supplied. Chemical reactions soften the surface and mechanical polishing removes it, planarizing wide areas with high precision. It is essential for forming multilevel interconnects.