Doping efficiency and limits in (Mg,Zn)O:Al,Ga thin films with two-dimensional lateral composition spread

作者：Mavlonov Abdurashid; Richter Steffen; von Wenckstern Holger; Schmidt Grund Ruediger; Lenzner Joerg; Lorenz Michael; Grundmann Marius

来源：Physica Status Solidi A-Applications and Materials Science, 2015, 212(12): 2850-2855.

DOI：10.1002/pssa.201431932

• doping
• (Mg,Zn)O
• pulsed laser deposition
• thin films
• transparent conductive oxides

We have investigated structural, optical, and electrical properties of MgxZn1-xO:(Al/Ga) thin films in dependence on Mg and Al/Ga concentrations. For this purpose, thin films with two perpendicular, lateral composition gradients, i.e., the Mg composition is varied in one direction whereas the Al/Ga concentration is varied in a perpendicular direction were grown at 600 degrees C by pulsed-laser deposition (PLD) using a threefold segmented PLD target and 2-inch in diameter c-plane sapphire substrates. It has been found that compensation by intrinsic acceptors limits efficient doping to dopant concentrations of about 2 x 10(21) cm(-3). Further, the electrical data suggests, that the compensating defect is doubly chargeable hinting to the zinc vacancy as microscopic origin. Increasing the dopant concentration above 2 x 10(21) cm(-3) leads to a degradation of electrical and structural properties.

• 出版日期2015-12