[amp_mcq option1=”Photo resist” option2=”Etching” option3=”Doping impurities” option4=”None of the mentioned” correct=”option3″]
The correct answer is C. Doping impurities.
Doping is the process of adding impurities to a semiconductor material to change its electrical properties. In the case of polysilicon, doping with boron or phosphorus atoms can reduce its resistivity.
Photo resist is a light-sensitive material that is used in photolithography to create patterns on a semiconductor wafer. Etching is a process that uses chemicals to remove material from a semiconductor wafer.
Neither photo resist nor etching are used to reduce the resistivity of polysilicon.