Investigation of the structural, electrical, and optical properties of MnAl₂Se₄ layers grown using the hot-wall deposition technique

Abstract

MnAl₂Se₄ layers were grown using the hot-wall deposition technique with an attached reservoir tail. Precise control of the vapor pressure in the reservoir was thought to play an important role in the grown of a stoichiometric layer. From the relation between the reciprocal temperature and the carrier concentration, we extracted the dominant trap level as 96.1 meV in the high-temperature region and 13.9 meV in the middle-temperature region. Thus, from a log-log plot between the mobility and the temperature, the mobility showed the different temperature-dependent decreases of the mobility at temperatures above 100 K: T ^−1/2 in the temperature range of 100 < T < 225 K and T ^−3/2 in the temperature of T > 225 K. The mobility decreased in proportion to T ¹ in the low-temperature range of T < 100 K. By analyzing the optical absorption results, the bandgap variation matched E _g (T) = E _g (0) − 3.19 × 10⁻³ T ²/(T + 488) well, where E _g (0) is estimated to be 3.5616 eV. Consequently, low-temperature growth of MnAl₂Se₄ layers was achieved by using the hot-wall deposition technique.