Abstract
In this work we first report on a theoretical model which provides the gate voltage dependence of the piezoelectric polarization charge in GaN HEMT devices. The model utilizes a generalization of Gauss' law, imposing constraints on the electric displacement vector D. The constraint on D is given by the continuity of the perpendicular component of the displacement vector across an interface. Poisson's equation is then solved across various layers under proper boundary conditions for the applied bias. The piezoelectric polarization charge is reduced due to the electromechanical coupling compared to the uncoupled case. Under high sheet electron densities, the correction in the piezoelectric polarization charge is also lower due to smaller electric fields. The theoretical model is then incorporated in the particle-based device simulator and device transfer and output characteristics are calculated without and with the bias dependent polarization charge. We find that percentage change in drain current increases with larger negative bias on the gate, due to the larger vertical electric fields.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 592-597 |
| Number of pages | 6 |
| Journal | Microelectronics Journal |
| Volume | 44 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 2013 |
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Keywords
- Electro-mechanical coupling
- GaN HEMTs
- Piezoelectric polarization charge
- Polarization charges
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
Cite this
Current degradation due to electromechanical coupling in GaN HEMT's. / Padmanabhan, Balaji; Vasileska, Dragica; Goodnick, Stephen.
In: Microelectronics Journal, Vol. 44, No. 7, 07.2013, p. 592-597.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Current degradation due to electromechanical coupling in GaN HEMT's
AU - Padmanabhan, Balaji
AU - Vasileska, Dragica
AU - Goodnick, Stephen
PY - 2013/7
Y1 - 2013/7
N2 - In this work we first report on a theoretical model which provides the gate voltage dependence of the piezoelectric polarization charge in GaN HEMT devices. The model utilizes a generalization of Gauss' law, imposing constraints on the electric displacement vector D. The constraint on D is given by the continuity of the perpendicular component of the displacement vector across an interface. Poisson's equation is then solved across various layers under proper boundary conditions for the applied bias. The piezoelectric polarization charge is reduced due to the electromechanical coupling compared to the uncoupled case. Under high sheet electron densities, the correction in the piezoelectric polarization charge is also lower due to smaller electric fields. The theoretical model is then incorporated in the particle-based device simulator and device transfer and output characteristics are calculated without and with the bias dependent polarization charge. We find that percentage change in drain current increases with larger negative bias on the gate, due to the larger vertical electric fields.
AB - In this work we first report on a theoretical model which provides the gate voltage dependence of the piezoelectric polarization charge in GaN HEMT devices. The model utilizes a generalization of Gauss' law, imposing constraints on the electric displacement vector D. The constraint on D is given by the continuity of the perpendicular component of the displacement vector across an interface. Poisson's equation is then solved across various layers under proper boundary conditions for the applied bias. The piezoelectric polarization charge is reduced due to the electromechanical coupling compared to the uncoupled case. Under high sheet electron densities, the correction in the piezoelectric polarization charge is also lower due to smaller electric fields. The theoretical model is then incorporated in the particle-based device simulator and device transfer and output characteristics are calculated without and with the bias dependent polarization charge. We find that percentage change in drain current increases with larger negative bias on the gate, due to the larger vertical electric fields.
KW - Electro-mechanical coupling
KW - GaN HEMTs
KW - Piezoelectric polarization charge
KW - Polarization charges
UR - http://www.scopus.com/inward/record.url?scp=84878926719&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84878926719&partnerID=8YFLogxK
U2 - 10.1016/j.mejo.2013.03.009
DO - 10.1016/j.mejo.2013.03.009
M3 - Article
AN - SCOPUS:84878926719
VL - 44
SP - 592
EP - 597
JO - Microelectronics
JF - Microelectronics
SN - 0026-2692
IS - 7
ER -