Universal distribution of residual carriers in tetrahedrally coordinated amorphous semiconductors

An uncommon electron spin resonance technique is used to show that a univer sal distribution of residual carriers exists in tetrahedrally coordinated a morphous semiconductors following optical excitation at low temperatures. T his universal behavior at long decay times results because statistical fluc tuations in the electron and hole densities cannot occur and therefore do n ot affect the kinetics. This behavior is: confirmed for carrier densities b etween 10(16) and 10(17) cm(-3) and decay times as long as 10(4) s.