Investigation of Charge Carrier Mobility of Tris(8-hydroxyquinolinato)aluminum Doped with Substituted Lithium Quinolate Complexes

The charge carrier mobility of doped tris(8-hydroxyquinolinato)aluminum (AlQ₃) have been investigated in detail. Substituted lithium quinolate complexes are used as molecular n-type dopant in AlQ₃. Dopant concentration dependent charge carrier mobility have been investigated in detail and compared. Effect of substituent (electron donating or withdrawing) on the dopant molecules have also been analysed. In this study, bilayer device structure was fabricated on the patterned ITO coated glass substrate. Applied field dependent mobility of the fabricated devices were investigated and analysed. The highest electron mobility of 1.63 × 10^–4 and 6.92 × 10^–5 cm²/V s for 20% LiMeQ and LiClQ doped AlQ₃, respectively at the applied electric field of 1050 (V/cm)^1/2.