On the role of hydrogen in metastable defect equilibration in undoped hydrogenated amorphous silicon

Etching of a-Si:H thin films by hydrogen plasma: A view from in situ spectroscopic ellipsometry

“…Such a discontinuity, in the case of undoped a-Si:H, may be linked to the thermal equilibrium temperature of this material. 35 Indeed, it is well established that the defect density in undoped a-Si:H can reach equilibrium above a temperature T E in the range 190-230 • C [36][37][38] and lower in doped a-Si:H. 39 Above T E , the defect density increases with an activation energy close to 0.2 eV. 35 Below T E , the defect density depends on the prior thermal history of the sample.…”