Metastable paramagnetism in hydrogenated amorphous silicon: Evidence for a new class of defects in tetrahedrally bonded amorphous semiconductors

After rapid cooling from 483 K, the characteristic electron-spin-resonance (ESR) signal in hydrogenated amorphous silicon ($a$-Si:H) has been observed to grow with time at room temperature. This increased ESR signal anneals at temperatures above ∼370 K. These results have a significant effect on our understanding of the electronic states in $a$-Si:H.