Transport characterizations and diodelike behaviour of Mn0.98CR0.02Te film prepared by pulsed laser deposition

MnTe is a kind of antiferromagnetic semiconductor with Néel temperature (TN) of 307 K. Mn_1-xCr_xTe was investigated as diluted magnetic semiconductor. The structure, magnetic and transport properties of MnTe and Mn_1-xCr_xTe films were investigated . In these previous works, some of the films represent different characteristic from the bulk ones, such as ferromagnetism at room temperature and the anomaly of resistivity below TN. Diodelike behavior is usually observed in semiconductor/metal systems because of forming p-n junctions, such as in glass-metal nanocomposite, due to the presence of metal-semiconductor junctions in the glasses, in which the metal particles of diameter about 2 nm behave as semiconductors. The diodelike behavior also was found in Si nanowires due to nonuniform composite. In this work, the Mn_0.98Cr_0.02Te films with island growth were prepared by pulsed laser deposition (PLD) . The transport properties were studied from 300 to 2 K, and a transformation from metal to semiconductor was found at about 220 K, which is shifted with changing measurement current . And a diodelike behavior was discovered near the transformation temperature.