Question

Silicon doped with gallium forms

• A. n-type semiconductor
• B. both n and p type semiconductor
• C. an intrinsic semiconductor
• D. p-type semiconductor

Answer 1

Answer: (D)

An intrinsic semiconductor is a semiconductor where we do not use any dopant, i.e. it is an undoped semiconductor.

Silicon has $4$ valence electrons whereas gallium has only $3$ valence electrons. Thus, the dopant has less number of valence electrons in this case. Hence, silicon doped with gallium forms a p-type semiconductor.