摘要
Short range order model is commonly used to explain the charge transport property of disordered organic semiconductors.However,its validity is not yet studied.In this paper,the hole and electron mobilities of a bipolar material,N,N'-dicarbazolyl-1,4dimethene-benzene(DCB),were measured through time of flight method.The hole and electron mobilities of DCB based on the crystalline structure were calculated.In order to investigate the short range order model,the ratios of charge mobilities at zero electric field of holes to electrons were calculated.The results showed that this model cannot fully explain our case.The reason was discussed in detail,and a correction method was proposed.We showed that using the short range order model without preconditions to explain the charge transport property of amorphous materials may lead to deviations,which is often neglected in the past.
Short range order model is commonly used to explain the charge transport property of disordered organic semiconductors. How- ever, its validity is not yet studied. In this paper, the hole and electron mobilities of a bipolar material, N,N'-dicarbazolyl-1,4- dimethene-benzene (DCB), were measured through time of flight method. The hole and electron mobilities of DCB based on the crystalline structure were calculated. In order to investigate the short range order model, the ratios of charge mobilities at zero electric field of holes to electrons were calculated. The results showed that this model cannot fully explain our case. The reason was discussed in detail, and a correction method was proposed. We showed that using the short range order model without precondi- tions to explain the charge transport property of amorphous materials may lead to deviations, which is often neglected in the past.
基金
supported by the National Basic Research and Development Program of China (2009CB623604)
the National Natural Science Foundation of China (50990060,51073809 and 61177023)