a The roomtemperature electrical conductivity of a semicondu

a) The room-temperature electrical conductivity of a semiconductor specimen is 25 (?·m)^-1. The hole concentration is known to be 2.5E+19 m^-3. The electron and hole mobilities for this material are 0.38 and 0.18 m²/V·s, respectively. Compute the electron concentration. (Use scientific notation.)

b) On the basis of the result in part (a), is the specimen intrinsic, n-type extrinsic, or p-type extrinsic?

a)

=_____m-3

Solution

conductivity= electronconcentration*electronmobility*q

25 = N_d*0.38*1.6*10^-19

   N_d = 4.1*10^20 m-3

here, Nd>>Na so it is a N⁺P semiconductors

it is n-type extrinsic