TY - JOUR
T1 - DC, RF, and microwave noise performances of AlGaN/GaN HEMTs on sapphire substrates
AU - Lu, W.
AU - Kumar, V.
AU - Schwindt, R.
AU - Piner, E.
AU - Adesida, I.
N1 - Funding Information:
Manuscript received February 16, 2001. This work was supported by the Defense Advanced Research Projects Agency under Contract DAAD19-99-1-0011, by the Office of Naval Research under Grant N00014-01-1-1000 and Grant N00014-01-1-1072 (monitor: Dr. J. Zolper).
PY - 2002/11
Y1 - 2002/11
N2 - High-performance AlGaN/GaN high electron-mobility transistors with 0.18-μm gate length have been fabricated on a sapphire substrate. The devices exhibited an extrinsic transconductance of 212 mS/mm, a unity current gain cutoff frequency (f T) of 101 GHz, and a maximum oscillation frequency (f MAX) of 140 GHz. At V ds = 4 V and I ds = 39.4 mA/mm, the devices exhibited a minimum noise figure (NF min) of 0.48 dB and an associated gain (G a) of 11.16 dB at 12 GHz. Also, at a fixed drain bias of 4 V with the drain current swept, the lowest NF min of 0.48 dB at 12 GHz was obtained at I ds = 40 mA/mm, and a peak G a of 11.71 dB at 12 GHz was obtained at I ds = 60 mA/mm. With the drain current held at 40 mA/mm and drain bias swept, the NF min increased almost linearly with the increase of drain bias. Meanwhile, the G a values decreased linearly with the increase of drain bias. At a fixed bias condition (V ds = 4 V and I ds = 40 mA/mm), the NF min values at 12 GHz increased from 0.32 dB at -55°C to 2.78 dB at 200°C. To our knowledge, these data represent the highest f T and f MAX, and the best microwave noise performance of any GaN-based FETs on sapphire substrates ever reported.
AB - High-performance AlGaN/GaN high electron-mobility transistors with 0.18-μm gate length have been fabricated on a sapphire substrate. The devices exhibited an extrinsic transconductance of 212 mS/mm, a unity current gain cutoff frequency (f T) of 101 GHz, and a maximum oscillation frequency (f MAX) of 140 GHz. At V ds = 4 V and I ds = 39.4 mA/mm, the devices exhibited a minimum noise figure (NF min) of 0.48 dB and an associated gain (G a) of 11.16 dB at 12 GHz. Also, at a fixed drain bias of 4 V with the drain current swept, the lowest NF min of 0.48 dB at 12 GHz was obtained at I ds = 40 mA/mm, and a peak G a of 11.71 dB at 12 GHz was obtained at I ds = 60 mA/mm. With the drain current held at 40 mA/mm and drain bias swept, the NF min increased almost linearly with the increase of drain bias. Meanwhile, the G a values decreased linearly with the increase of drain bias. At a fixed bias condition (V ds = 4 V and I ds = 40 mA/mm), the NF min values at 12 GHz increased from 0.32 dB at -55°C to 2.78 dB at 200°C. To our knowledge, these data represent the highest f T and f MAX, and the best microwave noise performance of any GaN-based FETs on sapphire substrates ever reported.
KW - AlGaN
KW - GaN
KW - HEMT
KW - Microwave noise
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U2 - 10.1109/TMTT.2002.804619
DO - 10.1109/TMTT.2002.804619
M3 - Article
AN - SCOPUS:0036853017
VL - 50
SP - 2499
EP - 2504
JO - IEEE Transactions on Microwave Theory and Techniques
JF - IEEE Transactions on Microwave Theory and Techniques
SN - 0018-9480
IS - 11 SPEC
ER -