<abstract xmlns="http://www.w3.org/1999/xhtml">The effect of germanium trapezoidal profile shape on the direct current (DC) current gain (<italic>β</italic>F), cut-off frequency (<italic>f</italic>T) and maximum oscillation frequency (<italic>f</italic>MAX) of silicon-germanium (SiGe) hetero-junction bipolar transistors (HBTs) has been investigated. The energy balance (EB), hydrodynamic (HD) and drift-diffusion (DD) physical transport models in SILVACO technology computer aided design (T-CAD) simulator were used. It was found that the current gain values using energy balance model are higher than hydrodynamic and much higher than those corresponding to drift-diffusion. Moreover, decreasing the germanium gradient slope towards the collector side of the base enhances the maximum oscillation frequencies using HD and EB models whilst, they remain stable for DD model.</abstract>

The effect of germanium trapezoidal profile shape on the direct current (DC) current gain (βF), cut-off frequency (fT) and maximum oscillation frequency (fMAX) of silicon-germanium (SiGe) hetero-junction bipolar transistors (HBTs) has been investigated. The energy balance (EB), hydrodynamic (HD) and drift-diffusion (DD) physical transport models in SILVACO technology computer aided design (T-CAD) simulator were used. It was found that the current gain values using energy balance model are higher than hydrodynamic and much higher than those corresponding to drift-diffusion. Moreover, decreasing the germanium gradient slope towards the collector side of the base enhances the maximum oscillation frequencies using HD and EB models whilst, they remain stable for DD model.

Germanium Gradient Optimization for High-Speed Silicon Germanium Hetero-Junction Bipolar Transistors

Laboratory of metallic and semiconducting materials

Materials Science and Informatics Laboratory

Annals of West University of Timisoara - Physics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

The effect of germanium trapezoidal profile shape on the direct current (DC) current gain (βF), cut-off frequency (fT) and maximum oscillation frequency (fMAX)...

Germanium Gradient Optimization for High-Speed Silicon Germanium Hetero-Junction Bipolar Transistors

Published Online: Jan 21, 2020

Page range: 22 - 32

Received: Sep 29, 2019

Accepted: Nov 27, 2019

DOI: https://doi.org/10.2478/awutp-2019-0002

Keywords
SiGe HBT, SILVACO, Trapezoidal profile, Current Gain, Cut-off frequency, Maximum oscillation frequency

© 2019 Abdelkader Khadir et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Germanium Gradient Optimization for High-Speed Silicon Germanium Hetero-Junction Bipolar Transistors

Published Online: Jan 21, 2020

Page range: 22 - 32

Received: Sep 29, 2019

Accepted: Nov 27, 2019

DOI: https://doi.org/10.2478/awutp-2019-0002

KeywordsSiGe HBT, SILVACO, Trapezoidal profile, Current Gain, Cut-off frequency, Maximum oscillation frequency

© 2019 Abdelkader Khadir et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
SiGe HBT, SILVACO, Trapezoidal profile, Current Gain, Cut-off frequency, Maximum oscillation frequency