Determination of the detailed nature of the semiconductor-to-metal transition in doped semiconductors is obscured by the random placement of the impurities. We report the results of a Monte Carlo percolation calculation which show that the details of the Hall-coefficient data in Si:P and, less clearly, in Ge:Sb are consistent with the existence of a discontinuous transition from insulator to metal at $T=0^{\circ }\mathrm{K}$ as the impurity concentration is increased.

• Received 3 February 1969

DOI:https://doi.org/10.1103/PhysRev.183.773