[19a-B12-1~11] 12.3 機能材料・萌芽的デバイス

▲ [19a-B12-5] Extracting Carrier Mobility Using a Photoinduced Charge Transfer Reaction: Assumptions, Errors, and Generalizations

〇Qingshuo Wei^1,2、Masakazu Mukaida¹、Kazuhiro Kirihara¹、Shohei Horike¹ (1.AIST、2.JST PRESTO)

キーワード：organic semiconductors, Carbon Nanotube, doping

Charge-carrier mobility is an important and crucial performance criterion for organic semiconductors and nanocarbon materials such as carbon nanotubes. Although high conductivity has been achieved in highly doped organic semiconductors and CNT networks, reliable measurements of charge-carrier mobility in such disordered materials remain a challenge. We developed and extended a new mobility measurement method, referred to as photoinduced charge transfer, from conducting polymers to nanocarbon materials. By studying the carrier mobility of standard samples and comparing it with Hall-effect measurements, we verified the validity of this approach. We successfully extended the approach to disordered CNT networks and provided evidence of the relationship between CNT structure and carrier mobility. We demonstrated that DWCNTs have higher carrier mobility than SWCNTs. The carrier mobility of SWCNTs is limited by the defect concentration in the film. This method can potentially be applied to a wide range of p-type conducting materials and opens new opportunities toward understanding the carrier mobility and other material properties, including thermoelectric properties.