Azaisoindigo conjugated polymers for high performance n-type and ambipolar thin film transistor applications - Yue,W; Nikolka,M; Xiao,M; Sadhanala,A; Nielsen,CB; White,AJP; Chen,H-Y; Onwubiko,A; Sirringhaus,H; McCulloch,I (JOURNAL OF MATERIALS CHEMISTRY C, 2016)