ON THE CORE OF THE THERMAL DONORS IN SILICON.

There is a hierarchy of double donors which arise upon annealing Czochralski silicon. The theory of the hierarchy of ground states argues that the core is Coulombic plus a repulsive contribution, i. e. , the electronic properties, such as the ground state energy, may not be grossly affected by the details of the interior of the core. The first thermal donor in the hierarchy is apt to be most affected by the core, but its maximum concentration never reaches that of the subsequent donors.