Question -
Answer -
Number of silicon atoms, N =5 × 1028 atoms/m3
Number of arsenic atoms, nAs =5 × 1022 atoms/m3
Number of indium atoms, nIn =5 × 1020 atoms/m3
Number of thermally-generated electrons, ni =1.5 × 1016 electrons/m3
Number of electrons, ne = 5 × 1022 − 1.5 × 1016 ≈4.99 × 1022
Number of holes = nh
In thermalequilibrium, the concentrations of electrons and holes in a semiconductor arerelated as:
nenh = ni2
Therefore, the number of electrons isapproximately 4.99 × 1022 and the number of holes is about 4.51 × 109. Since the number of electrons is more than thenumber of holes, the material is an n-type semiconductor.