Question

what is the donor concentration in n-type germanium of 1ohm-cm resistivity at 300K given electron mobility is equals to 3900cm²/V.s

Answer 1

$$ρ= \frac {1} {nqμ_n} (1)$$

Using (1) we got:

$$n=\frac {1} {ρqμ_n} (2),$$

where ρ=1ohm×cm, q=1.6×10^-19 C, μn=3900cm²/V.s

In this case, n=1.6×10¹⁴ cm^-3

Answer:

1.6×10¹⁴ cm^-3