TY - JOUR
T1 - 0.15-μm-Gate InAlAs/InGaAs/InP E-HEMTs utilizing Ir/Ti/Pt/Au gate structure
AU - Kim, Seiyon
AU - Adesida, Ilesanmi
N1 - Funding Information:
Manuscript received May 15, 2006; revised August 11, 2006. This work was supported by the Office of Naval Research (ONR) under Grant N00014-02-10018 (Program Manager: Dr. D. Purdy) and by the National Science Foundation (NSF) under Grant ANI 01-21662 ITR. The review of this letter was arranged by Editor T. Mizutani.
PY - 2006/11
Y1 - 2006/11
N2 - High-current 0.15-μ-gate enhancement-mode high-electron mobility transistors utilizing Ir/Ti/Pt/Au gate metallization were fabricated using a new process including a high-temperature gate anneal that is required for Schottky-barrier height enhancement for the Ir-based gate contact. SiNx encapsulation was employed to prevent thermal degradation of device layer during the high-temperature gate anneal. Excellent enhancement-mode operation, with a threshold voltage of 0.1 V and IDSS of 2.1 mA/mm, was realized. Both the annealed and unannealed devices exhibited high gm,max and ID,max 800 mS/mm and 430 mA/mm, respectively. A unity current-gain cutoff frequency fT of 151 GHz and a maximum oscillation frequency fMAX of 172 GHz were achieved. From the dc and RF characteristics, it can be deduced that there was no degradation of the gate contact and the heterostructure due to gate annealing. Furthermore, it was found that the gate diffusion during gate annealing was negligible since no increase in gm,max was observed.
AB - High-current 0.15-μ-gate enhancement-mode high-electron mobility transistors utilizing Ir/Ti/Pt/Au gate metallization were fabricated using a new process including a high-temperature gate anneal that is required for Schottky-barrier height enhancement for the Ir-based gate contact. SiNx encapsulation was employed to prevent thermal degradation of device layer during the high-temperature gate anneal. Excellent enhancement-mode operation, with a threshold voltage of 0.1 V and IDSS of 2.1 mA/mm, was realized. Both the annealed and unannealed devices exhibited high gm,max and ID,max 800 mS/mm and 430 mA/mm, respectively. A unity current-gain cutoff frequency fT of 151 GHz and a maximum oscillation frequency fMAX of 172 GHz were achieved. From the dc and RF characteristics, it can be deduced that there was no degradation of the gate contact and the heterostructure due to gate annealing. Furthermore, it was found that the gate diffusion during gate annealing was negligible since no increase in gm,max was observed.
KW - Enhancement-mode high-electron mobility transistor (E-HEMT)
KW - InP E-HEMT
KW - Iridium gate
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U2 - 10.1109/LED.2006.883563
DO - 10.1109/LED.2006.883563
M3 - Article
AN - SCOPUS:33750510501
SN - 0741-3106
VL - 27
SP - 873
EP - 876
JO - IEEE Electron Device Letters
JF - IEEE Electron Device Letters
IS - 11
ER -