LIGHT-INDUCED METASTABLE DEFECTS IN A-SI-H STUDIED BY TRANSIENT SPACE-CHARGE PERTURBED CURRENTS

After a transit time, the transient space charge perturbed current in an n-i-n a-Si:H device is given by j = f(t)CV2-mu(d)(t)L2 where f(t) is the fraction of electrode limitation, 0 < f(t) < 9/8 and-mu-d(t) is the time dependent drift mobility. Metastable defects located deep in the gap only affect the mobility at long times; hoever f(t) is responsive to the short time decay of the current. We present data in n-i-n and p-i-n devices showing that both f(t) and mu(d)(t) are affected by photodegradation.