Gate tunnelling and impact ionisation in sub 100 nm PHEMTs

K. Kalna1, A. Asenov1
1Device Modelling Group, Department of Electronics & Electrical Engineering, University of Glasgow, Glasgow, UK

Tóm tắt

Impact ionization and thermionic tunnelling as two possible breakdown mechanisms in scaled pseudomorphic high electron mobility transistors (PHEMTs) are investigated by Monte Carlo (MC) device simulations. Impact ionization is included in MC simulation as an additional scattering mechanism whereas thermionic tunnelling is treated in the WKB approximation during each time step in selfconsistent MC simulation. Thermionic tunnelling starts at very low drain voltages but then quickly saturates. Therefore, it should not drastically affect the performance of scaled devices. Impact ionization threshold occurs at greater drain voltages which should assure a reasonable operation voltage scale for all scaled PHEMTs.

Từ khóa

#Tunneling #Impact ionization #PHEMTs #Threshold voltage #Electric breakdown #Electron mobility #HEMTs #MODFETs #Monte Carlo methods #Scattering

Tài liệu tham khảo

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