Display panel, its manufacturing method, and display device

A method for manufacturing a display panel, comprising steps of:

• forming, on a substrate, a thin film transistor comprising a gate electrode, an active layer, a source electrode and a drain electrode;
• forming a hydrogen diffusion barrier layer that covers the entire substrate, wherein the hydrogen diffusion barrier layer is electrically conductive and is electrically connected to the drain electrode;
• and
• forming a photosensitive structure layer on the hydrogen diffusion barrier layer, wherein the step of forming the photosensitive structure layer on the hydrogen diffusion barrier layer comprises:
• depositing an N-type amorphous silicon thin film on the hydrogen diffusion barrier layer by adopting a plasma enhanced chemical vapor deposition process;
• depositing an intrinsic amorphous silicon thin film on the N-type amorphous silicon thin film;
• and
• subjecting the intrinsic amorphous silicon thin film to ion implantation, and subjecting the ion-implanted intrinsic amorphous silicon thin film to activation treatment to form a P-type amorphous silicon thin film on an upper layer of the intrinsic amorphous silicon thin film.