부산대학교 도서관

In this work, High Electron Mobility Transistor is grown on various Substrates such as silicon (Si), silicon carbide (SiC), and sapphire substrate to exhibit a negative threshold voltage, whereas grown on β-gallium oxide (β-Ga2O3) to exhibit a positive threshold voltage. The optimization is done by using the pi-shaped gate and filed plate towards the drain and triple tooth metal for the proposed structure. In this, work Al0.8Ga0.2 N /AlN /GaN /AlN /Al0.4Ga0.6 N /GaN /AlN / Al0.8Ga0.2 N / β-Ga2O3 HEMT is proposed to improve the breakdown voltage, subthreshold swing. Β-Ga2O3 is prominent material to reduce the leakage current in the structure. It is observed from the obtained results that the Breakdown voltage for Si is 15 V, SiC is 20 V, Sapphire is 114 V, β-Ga2O3 is 125 V,d Unilateral power gain of 21.12dB, 19.56dB, 18.9dB, 9.5dB, at 851 GHz, 774 GHz, 738 GHz, 318 GHz when the proposed structure is grown on β-Ga2O3, SiC, Sapphire, Si substrates. In the proposed HEMT there is a compromise between frequency and breakdown voltage. If one factor improves the other reduces. But by using β-Ga2O3 as a substrate the achievement of both factors is possible. This is possible because of properly layering hetero-materials with matched lattice constant. β-Ga2O3 is a material that is a trend in the market and which resulted in intensive research. In the proposed structure Ferroelectric material i.e. lead Zirconate titanate oxide (PbZrTiO3) is used as a gate to reduce the power consumption and to increase the storage capacity in a unit area. Ferroelectric materials possess elevated dielectric constant and it has the capability of storing more charge per unit area when compared to other materials. In the small area, this material can store more data with low power consumption.