Consider three semiconductor materials that all have the sam

Consider three semiconductor materials that all have the same crystal structure. Material A has a band gap of 1 eV and a lattice constant of 5 Angstrom; material B has a band gap of 1 eV and a lattice constant of 6 Angstrom, and material C has a band gap of 2 eV and a lattice constant of 6 Angstrom. What do you expect for the intrinsic electron concentration (n = # of electrons/unit volume) at room temperature? (Recall that the lattice constant refers to the edge length of the unit cell.)

nA < nB < nC

nA > nB > nC

nA = nB < nC

nA < nB = nC

nA > nB = nC

The answer cannot be determined from the information given.

Solution

The answer is nA=nB<nC

Because the intrinsic carrier constant is lower in higher band gap materials. So here material C has high band gap comparing with A and B so nC is less than nA and nB. Material A and B have same energy gap so nA=nB