Highly conductive and transparent alumina-doped ZnO films processed by direct pulsed laser recrystallization at room temperature

Abstract

Highly conductive and transparent alumina-doped ZnO (AZO) thin films (250 nm) are deposited at room temperature using pulsed laser deposition (PLD) and direct pulsed laser recrystallization (DPLR). Morphological characterizations show that the AZO films undergo recrystallization and growth during DPLR, which leads to less internal imperfections in AZO films and hence better film conductance. Electrical-optical characterizations show that DPLR results in significant improvement in conductivity, Hall mobility, and transmission from UV to NIR regions. Decrease in carrier concentration density in AZO film is observed. Compared with PLD, DPLR processed AZO films also possess smaller band gap which leads to broader solar spectrum acceptance.