TY - JOUR
T1 - Effects of gate sidewall recess on Al0.2Ga0.8 As/In0.15Ga0.85As PHEMTs by citric-based selective etchant
AU - Yarn, K. F.
AU - Liao, C. I.
AU - Wang, Y. H.
AU - Houng, M. P.
N1 - Funding Information:
The authors would like to thank K. K. Wu, M. C. Chure, S. H. Chang and Far East College for their kindly assistance and the support of film growth during this work.
PY - 2005/8
Y1 - 2005/8
N2 - In this report, an effective and simple method of selective gate sidewall recess is proposed to expose the low barrier channel at mesa sidewalls during device isolation for Al0.2Ga0.8 As/In0.15Ga0.85As PHEMTs (pseudomorphic high electron mobility transistors) by using a newly developed citric-acid-based etchant with high selectivity (>250) for GaAs/ Al0.2Ga0.8As or In0.15Ga0.85 As/Al0.2G0.8As interfaces. After sidewall recess, a revealed cavity will exist between the In0.15 Ga0.85As layers and gate metals. Devices with 1 × 100 μm2 exhibit a very low gate leakage current of 2.4 μA/mm even at VGD = -10 V and high gate breakdown voltage over 25 V. As compared to that of no sidewall recess, nearly two orders of reduction in magnitude of gate leakage current and 100% improvement in gate breakdown voltage can be achieved.
AB - In this report, an effective and simple method of selective gate sidewall recess is proposed to expose the low barrier channel at mesa sidewalls during device isolation for Al0.2Ga0.8 As/In0.15Ga0.85As PHEMTs (pseudomorphic high electron mobility transistors) by using a newly developed citric-acid-based etchant with high selectivity (>250) for GaAs/ Al0.2Ga0.8As or In0.15Ga0.85 As/Al0.2G0.8As interfaces. After sidewall recess, a revealed cavity will exist between the In0.15 Ga0.85As layers and gate metals. Devices with 1 × 100 μm2 exhibit a very low gate leakage current of 2.4 μA/mm even at VGD = -10 V and high gate breakdown voltage over 25 V. As compared to that of no sidewall recess, nearly two orders of reduction in magnitude of gate leakage current and 100% improvement in gate breakdown voltage can be achieved.
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U2 - 10.1007/s10854-005-2728-z
DO - 10.1007/s10854-005-2728-z
M3 - Article
AN - SCOPUS:24944472944
SN - 0957-4522
VL - 16
SP - 529
EP - 532
JO - Journal of Materials Science: Materials in Electronics
JF - Journal of Materials Science: Materials in Electronics
IS - 8
ER -