Modelling and Simulation of Normally-Off AlGaN/GaN MOS-HEMTs

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The article presents the results of modelling and simulation of normally-off AlGaN/GaN MOS-HEMT transistors. The effect of the resistivity of the GaN:C layer, the channel mobility and the use of high-k dielectrics on the electrical characteristics of the transistor has been examined. It has been shown that a low leakage current of less than 10−6 A/mm can be achieved for the acceptor dopant concentration at the level of 5 X 1015 cm−3. The limitation of the maximum on-state current due to the low carrier channel mobility has been shown. It has also been demonstrated that the use of HfO2, instead of SiO2, as a gate dielectric increases on-state current above 0.7A/mm and reduces the negative influence of the charge accumulated in the dielectric layer.

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International Journal of Electronics and Telecommunications

The Journal of Committee of Electronics and Telecommunications of Polish Academy of Sciences

Journal Information

CiteScore 2016: 0.72

SCImago Journal Rank (SJR) 2016: 0.248
Source Normalized Impact per Paper (SNIP) 2016: 0.542

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