We show that, in n-doped semiconductors under continuous laser illumination the homogeneous steady-state of carriers becomes, in the degenerate regime, unstable against the formation of spatial order at the macroscopic level. Beyond a critical distance from equilibrium this nonequilibrium phase transition occurs, corresponding to the formation of a polarization wave of electrons and holes. It is the result of the interplay of collective and nonlinear dissipative effects in the far-from-equilibrium system. © 1990.749889892Nicolis, Prigogine, (1977) Self-Organization in Nonequilibrium Systems, , Wiley, New YorkHaken, (1978) Synergetics, , Springer, Berlin-HeidelbergTuring, The Chemical Basis of Morphogenesis (1952) Philosophical Transactions of the Royal Society B: Biological Sciences, 237 B, p. 37For a review of the NSOM and its applications see: R. Luzzi and A.R. Vasconcellos, Fortsch. Phys. No. 1, Band 39 (in press)(1985) Rev. Brasil. Fis., 15, p. 106. , also(1986) Rev. Brasil. Fis., 16, p. 495(1987) Rev. Brasil. Fis., 17, p. 601Zubarev, (1971) Neravnovesnaia Statisticheskaia Termodinamika, , Izd, Nauka, Moskwa(1974) Nonequilibrium Statistical Thermodynamics, , New YorkTomé, Vasconcellos, Luzzi, (1987) Physica, 144 B, p. 376Davies, (1962) Nonlinear Integral and Differential Equations, , Dover, New York, also in Ref. (1), Part II, Section 6For a review of the NSOM and its applications see: R. Luzzi and A.R. Vasconcellos, Fortsch. Phys. No. 1, Band 39 (in press)van Vechten, IMPORTANCE OF THE PLASMA TO PULSED LASER ANNEALING (1980) Le Journal de Physique Colloques, 41 C, p. 4. , Solid State Commun. 39 1981 1835A.S. Esperidião, A.R. Vasconcellos and R. Luzzi, Solid State Commun. (in press)