This title appears in the Scientific Report :
2006
Please use the identifier:
http://dx.doi.org/10.1109/TED.2006.885681 in citations.
Current collapse and high-electric-field reliability of unpassivated GaN/AlGaN/GaN HEMTs
Current collapse and high-electric-field reliability of unpassivated GaN/AlGaN/GaN HEMTs
Long-term ON-state and OFF-state high-electric-field stress results are presented for unpassivated GaN/AlGaN/GaN high-electron-mobility transistors on SiC substrates. Because of the thin GaN cap. layer, devices show minimal current-collapse effects prior to high-electric-field stress, despite the fa...
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Personal Name(s): | Meneghesso, G. |
---|---|
Rampazzo, F. / Kordos, P. / Verzellesi, G. / Zanoni, E. | |
Contributing Institute: |
Institut für Halbleiterschichten und Bauelemente; ISG-1 |
Published in: | IEEE Transactions on Electron Devices, 53 (2006) S. 2932 - 2941 |
Imprint: |
2006
|
Physical Description: |
2932 - 2941 |
DOI: |
10.1109/TED.2006.885681 |
Document Type: |
Journal Article |
Research Program: |
Grundlagen für zukünftige Informationstechnologien |
Series Title: |
IEEE Transactions on Electron Devices
53 |
Subject (ZB): | |
Publikationsportal JuSER |
Long-term ON-state and OFF-state high-electric-field stress results are presented for unpassivated GaN/AlGaN/GaN high-electron-mobility transistors on SiC substrates. Because of the thin GaN cap. layer, devices show minimal current-collapse effects prior to high-electric-field stress, despite the fact that they are not passivated. Thin comes at the price of a relatively high gate-leakage current. Under the assumption that donor-like electron traps are present within the GaN cap, two-dimensional numerical device simulations provide an explanation for the influence of the GaN cap layer on current collapse and for the correlation between the latter and the gate-leakage current. Both ON-state and OFF-state stresses produce simultaneous current-collapse increase and gate-leakage-current decrease, which can be interpreted to be the result of gate-drain surface degradation and reduced gate electron injection. This study shows that although the thin GaN cap layer is effective in suppressing surface-related dispersion effects in virgin devices, it does not, per se, protect the device from high-electric-field degradation, and it should, to this aim, be adopted in conjunction with other technological solutions like surface passivation, prepassivation surface treatments, and/or field-plate gate. |