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Influence of barrier and spacer layer on structural and electrical properties of AlGaN/GaN HEMT

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A systematic numerical simulation of AlGaN/GaN-based HEMT is performed to demonstrate a strong dependence between the thickness and content of Al in the barrier layer on the electrical characteristics of HEMT. The impact of introducing a thin AlN spacer layer is also studied. A high mobility of 1901.2 cm2/Vs and an electron concentration of 3.036 × 1013 cm−2 is achieved by adding an AlN spacer in the standard AlGaN/GaN HEMT having barrier thickness as 27 nm and Al composition of 25%, while electron mobility and electron density of 1767 cm2/Vs and 2.778 × 1013 cm−2, respectively, is achieved for a standard optimized AlGaN/GaN structure. It is further presented that optimization of HEMT structure using numerical simulation tools is an efficient method of improving the electrical properties of the transistor structure preceding the fabrication of the device.

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The work has been supported by Defence Research and Development Organization, Govt. of India (CC/TM/ERIPR/GIA/16-17/008). Madhulika acknowledges the financial support from University Grants Commission (UGC), Government of India.

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Correspondence to Arun Kumar Singh.

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Madhulika, Jain, N., Kumar, S. et al. Influence of barrier and spacer layer on structural and electrical properties of AlGaN/GaN HEMT. Int. j. inf. tecnol. 12, 119–124 (2020). https://doi.org/10.1007/s41870-019-00348-0

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  • 2DEG
  • AlGaN/GaN
  • AlN
  • Electron mobility heterostructure
  • High-frequency
  • High-power
  • Numerical simulation
  • Spacer layer
  • Transconductance