Optoelectronic performance enhancement in pulsed laser deposited gallium-doped zinc oxide (GZO) films after UV laser crystallization

Abstract

This study investigates the process–microstructure–property relationship during a UV laser crystallization of a transparent conductive layer—gallium doped zinc oxide (GZO) films after pulsed laser deposition (PLD). UV laser induced crystallization technique is able to apply ultra-fast post-treatment to modify GZO films with better structural and optoelectronics properties, suggesting a potential for large-scale manufacturing. A physical simulation model coupled laser–matter interaction and heat-transfer was utilized to study pulse laser heating and heat dissipation process. The laser crystallized GZO film exhibits low resistivity of ~ 3.2 × 10−4 Ω cm, high-Hall mobility of 22 cm2/V s, and low sheet resistance of 22 Ω/sq. High-transmittance (T) over 90% at 550 nm is obtained (with glass substrate). The optoelectronic performance improved mainly attributes to grain boundary modification in the polycrystalline film, e.g., decrease of grain boundary density and passivation of electron trap at grain boundaries.