Organic Bistable Devices Based On Cross-linked PVP

The polymer memory device is one of the important directions in the next generation electronics because of their flexibility,transparency,low cost,simple preparation,and large area production.In this work,the cross-linking is introduced to the bilayer/multilayer polymer electrical bistable devices since the lower polymer layer can be dissolved by the upper layer solvent when spin coating the upper polymer layer.This work focuses on the application of' the cross-linked polymer film in the electrical bistable device and studies the device electrical bistability.The main contents are as follows:(1)The properties of the cross-linked PVP film were studied,including solvent resistance,surface contact angle,and surface morphology.Then,the cross-linked PVP film electrically characterized based on the Glass/ITO/cross-linked PVP/Al device.The results show that the cross-linking performance is the best when the PVP is annealed at 200 ? for 1 hour.(2)The optimized cross-linked PVP film is introduced in the PCBM/PVP electrical bistable devices and the device performance is improved.The results show that the on/off ratio of the electrical current curve is up to 2×102,which is significantly better than that of the device based on uncross-linked PVP.In addition,linear I-V curve fitting of the device shows that the PCBM in the active layer acts as a charge carrier capture center,which is the key reason for the electrical bistability.(3)The electrical bistable devices based on the cross-linked PVP and nano-Au system are demonstrated.The structure of the device is Glass/ITO/cross-linked PVP/nano Au/Al,and the maximum switching ratio is up to 2×103.The underlying mechanism of the electrical bistability is investigatecd.(4)By comparing the above two devices,it is found that,in the cross-linked PVP electric bistable devices,the nano-Au based device exhibits better performances than the PCBM based device.