PYQ Vault
EbooksTutor

Minority carrier concentration after doping, using n_e x n_h = n_i^2

This type of question, asked 3 times: 22 Apr 2025 S1, 13 Apr 2026 S2, 12 May 2026 S2. All 3 questions below, oldest first.

Try each one first, then open its answer.

  1. Question 1

    22 Apr 2025 S1

    4
    In a pure silicon crystal electron-hole concentration is 101610^{16} per m3m^{3} at 301 K . Now 102110^{21} atoms of phosphorus are added per cubic meter. The new hole concentration in silicon is (in per m3m^{3})

    Tap an option to check your answer.

  2. Question 2

    13 Apr 2026 S2

    148
    A pure silicon crystal at temperature 300300 K has electron and hole concentration (ni)(n_i) 101610^{16} per m3\mathrm{m^3} each and 102110^{21} phosphorus atoms (ne)(n_e) are added per cubic metre. The new hole concentration in silicon crystal is

    Tap an option to check your answer.

  3. Question 3

    12 May 2026 S2

    148
    Pure silicon crystal at 300300K has equal electron and hole concentration 2×10162 \times 10^{16} per m3^3. Doping by indium increases hole concentration to 4×10224 \times 10^{22} per m3^3. Electron concentration in doped silicon is

    Tap an option to check your answer.