The band tail effect on the thermal emission (TE) integrated power and
the spectral distribution (lambda = 3-5 mum) in n-InAs (N(d) - N(a) =
1.6 x 10(16) cm-3) has been investigated for the first time. The Urba
ch parameter T(eff) has been determined in the temperature range 310-4
00 K. Some practical uses for the results obtained are also discussed.