Nanorod assisted lateral epitaxial overgrowth of ZnO films in water at 90 °C

Abstract

A novel method was used to grow epitaxial ZnO films by employing a nanorod assisted lateral epitaxial overgrowth process at a low growth temperature of 90 °C in water utilizing a continuous circulation reactor. The relatively smooth films had an epitaxial relationship with the sapphire substrate, as confirmed by off-axis φ scans. Films grown for 72 hours had a high carrier concentration of 3.12 × 10¹⁸ cm⁻³ and mobility of 9.75 cm² V⁻¹ s⁻¹ after thermal treatment at 300 °C. The threading dislocation density of the thickest film was 5 × 10⁸ cm⁻², 2 orders of magnitude lower than that of normal solution grown ZnO films.