Abstract:
Diluted magnetic semiconductors have evolved as a fascinating area of research for potential spintronics applications at practical temperature. The generic problem of resistance mismatch at metal-semiconductor interfaces hinders the effective spin injection therefore; much attention is being focused on the development of room temperature ferromagnetic semiconductors. If successful, we could have new generation devices having miniaturation, high energy efficiency, non-volatile memory, large Zeeman splitting and high speed devices e.g. the Spin-field effect transistors (SFET), Spin light emitting diode (SLED) etc. In order to bring these materials into practical application, we need a ferromagnetic semiconductor showing ferromagnetism above room temperature. In order to achieve this challenge, i.e. making a non-magnetic semiconductor into ferromagnetic semiconductor, several theoretical and experimental works are being carried out in this field. Several theoretical and experimental works have been done on Chalcogenides based magnetic semiconductors and transition element doped Group II-VI, Group III-V and Group IV-VI semiconductors. However in the above class of materials, the ferromagnetic transition temperature is quite below room temperature. Another interesting group of DMS materials are the transition element doped wide band gap oxide semiconductors. of available models are yet to be carried out. At the beginning of the thesis work and as per literature survey, it was observed that, there were several reports on the TM doped ZnO and TiO2 based DMS with room temperature.
