Performance Improvement of Electron Devices Based on Magnetic Tunnel Junction Inserted Superlattice Structures

Abstract

Superlattice based heterojunction devices are becoming increasing popular newlinedue to its improved performance. There are many notable superlattice structure based newlinedevices such as photovoltaic device, transistors, lasers, LED s, photo detectors etc. newlineSuperlattice structure based devices made of dilute magnetic semiconductor (DMS) newlinetunnel junctions outperforms other superlattice structures made of non-magnetic newlinematerials. This is due to the improved electron transport with in the device structure newlinewith spin magnetic moments. One such approach is adopted in the present work to newlinecome up with a novel DMS based superlattice structure for photovoltaic and high newlineelectron mobility transistor (HEMT) devices. newlinePerformance of the HEMT devices can be further improved by proper design of newlinethe channel region of the device. To further improve the HEMT device performance, newlinethe channel was modelled with the CNT and DMS layers at both the ends of the newlinechannel. The superlattice structure made of the Si/DMS/CNT/DMS/Si has resulted in newlinea very high conductivity and electron density with almost ten folds higher than the DMS newlinebased superlattice structure. The improved conductivity of the proposed superlattice newlinedevice structure with CNT is due to the reduced scattering and possible 2 dimensional newlineelectron gas (2DEG). The 2 DEG structure is due to the band alignment of the newlinesuperlattice structure. newlineSuperlattice structure analysis based on the physical modelling was further newlinejustified with the electronic device modelling based on the drift diffusion calculations. newlineThe calculations performed with the electron density and the electrostatic potential has newlineconfirmed the performance improvement of the superlattice structure made of DMS newlineoptical spacer in the heterojunction photovoltaic device. The performance of the device newlinewas analysed by comparing the efficiency of the existing device structure and the newlinesuperlattice device structure.