Polycrystalline Ga(x)In(1-x)As films with x ranging from 0 to 1 were deposited on glass substrates by molecular-beam deposition at 240 or 350 degrees C. Room temperature Hall-effect measurements showed that the Ga(x)In(1-x)As films deposited at either temperature exhibit high electron concentrations in the range of 10(18) cm(-3) for x <= 0.21 while the electron concentration decreases with increasing Ga content for x >= 0.29 to be <10(15) cm(-3) at x = 0.64. Even at the low deposition temperature of 240 degrees C, the electron mobility remains>400 cm(2)/(V s) at x-0.2 and then decreases with Ga content to be similar to 40 cm(2)/(V s) at x = 0.64. Temperature-varying Hall-effect measurements in the range of 100-390 K revealed that both the electron concentration and mobility of the samples with x <= 0.21 are almost independent of the measurement temperature, while those of the samples with x <= 0.30 decrease with decreasing measurement temperature. The concentrations and ionization energies of donor levels were deduced from the temperature dependence of the electron concentration with the non-parabolicity of the conduction band taken into account. The temperature dependences of electron mobility in the samples with x >= 0.30 are well explained in terms of thermionic electron emission across the grain-boundary barriers assuming fluctuation in potential barrier height, while the almost temperature-independent high electron mobilities in the samples with x <= 0.21 are attributed to the absence of potential barrier at the grain boundaries. (C) 2010 Elsevier B.V. All rights reserved.