Temperature dependent spin injection properties of the Ni nanodots embedded metallic TiN matrix and p-Si heterojunction

• Published in: Thin solid films 2013-11, Vol.546, p.211-218
• Main Authors: Panda, J., Chattopadhyay, S., Nath, T.K.
• Format: Article
• Language: English
• Subjects: Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electrical properties of specific thin films; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronics; Epitaxial growth; Epitaxial Ni nanoparticle; Exact sciences and technology; Heterojunctions; Junction magnetoresistance; Magnetoelectric, magnetostrictive, magnetoacoustic, magnetooptic and magnetothermal devices. Spintronics; Materials science; Nanocontacts; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nickel; Operating temperature; Other topics in nanoscale materials and structures; Physics; Poole–Frenkel emission; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Spin injection; Spintronics; Titanium nitride; Transport
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2013.05.120

A detailed experimental investigation on magnetic field dependent electronic transport across epitaxial Ni nanoparticles embedded in metallic epitaxial TiN matrix grown on p-type (001) Si substrate heterojunction employing sequential exposure of pulsed excimer laser is reported here. The non-linear current–voltage characteristics along with good rectifying diode like behavior of the junction have been obtained in the range of 100–300K. The ideality factor, reverse saturation current, series resistance and turn-on voltages have been estimated for the heterojunction at different operating temperatures. The dominating current transport mechanism is found to be temperature dependent tunneling assisted Frenkel–Poole type emission. A crossover from negative to positive junction magnetoresistance (JMR) has been observed at ~190K (blocking temperature of the Ni nanodots). The JMR attains a peak with high positive JMR value at 250K, the origin of which has been best explained using standard spin injection theory. •Junction magnetoresistance (JMR) of TiN(Ni)/p-Si heterojunction is studied.•Current–voltage characteristics show good rectifying diode like behavior.•The junction shows the Frenkel–Poole type tunneling behavior.•At 190K, the JMR shows sign reversal.•The high value of JMR is best explained using standard spin injection theory.