Properties and electrical evolution of ambipolar SnOx thin films grown by atomic layer deposition in low temperature range

The ambipolar SnOx film is a promising substitution for organic material as hole transport or interconnection layer in perovskite devices, and low temperature process is essential to avoid the decomposition and thermal stress of the perovskite material. In this work, we prepared the ambipolar SnOx thin film via atomic layer deposition in low temperature range of 40-120 degrees C, and systematically investigated the surface morphology, wettability, chemical, optical and electrical properties. The obvious absorption band in near-infrared revealed the mid-gap band which contributes to the hole transport for SnOx films. The film displayed only hole transport behavior with the mobility of 1.25 x 10(-3) cm(2) v(-1) s(-1) at 40 degrees C, and achieved best ambipolar property at 100 degrees C with the electron mobility of 4.84 x 10(-3) cm(2) v(-1) s(-1) and the hole mobility of 1.15 x 10(-3) cm(2) v(-1) s(-1). This study provides a practical approach to manipulate the carrier transport behavior, chemical, and optical property of ALD SnOx thin film deposited in low temperature range, boosting their further exploration and high-performance development in different device structures which apply p-n junctions.