InA1N/GaN high-electron mobility transistors （HEMTs） with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/A1/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF...InA1N/GaN high-electron mobility transistors （HEMTs） with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/A1/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF characteristics of the devices were measured. The fabricated devices show a maximum drain current density of 2.18 A/mm at VGs = 2 V, a low on-resistance （Ron） of 1.49 x2.mm and low gate leakage current. An excellent frequency response was also obtained. The current cut-off frequency （fT） is 81 GHz and the maximum oscillation frequency is 138 GHz, respectively.展开更多
We report the DC and RF performance of InAlN/GaN high-electron mobility transistors with AlGaN back barrier grown on SiC substrates. These presented results confirm the high performance that is reachable by InAlN-base...We report the DC and RF performance of InAlN/GaN high-electron mobility transistors with AlGaN back barrier grown on SiC substrates. These presented results confirm the high performance that is reachable by InAlN-based technology. The InAlN/GaN HEMT sample showed a high 2DEG mobility of 1550 cmE/（V-s） at a 2DEG density of 1.7 × 1013 cm-2. DC and RF measurements were performed on the unpassivated device with 0.2 μm ＂T＂ gate. The maximum drain current density at Vcs = 2 V is close to 1.05 A/mm in a reproducible way. The reduction in gate leakage current helps to increase the frequency performance of AlGaN back barrier devices. The power gain cut-off frequency of a transistor with an A1GaN back barrier is 105 GHz, which is much higher than that of the device without an A1GaN back barrier at the same gate length. These results indicate InAlN/GaN HEMT is a promising candidate for millimeter-wave application.展开更多
InA1N has been studied by means of temperature-dependent time-integrated photoluminescence and time-resolved photoluminescence. The variation of PL peak energy did not follow the behavior predicted by Varshni formula,...InA1N has been studied by means of temperature-dependent time-integrated photoluminescence and time-resolved photoluminescence. The variation of PL peak energy did not follow the behavior predicted by Varshni formula, and a faster redshift with increasing temperature was observed. We used a model that took account of the thermal activation and thermal transfer of localized excitons to describe and explain the observed behavior. A good fitting to the experiment result is obtained. We believe the anomalous temperature dependence of PL peak energy shift can be attributed to the temperature-dependent redistribution of localized excitons induced by thermal activation and thermal transfer in the strongly localized states. V-shaped defects are thought to be a major factor causing the strong localized states in our ln0.153Al0.847N sample.展开更多
lnA1N/GaN high-electron-mobility transistors （HEMTs） on SiC substrate were fabricated and character- ized. Several techniques, consisting of high electron density, 70 nm T-shaped gate, low ohmic contacts and a short...lnA1N/GaN high-electron-mobility transistors （HEMTs） on SiC substrate were fabricated and character- ized. Several techniques, consisting of high electron density, 70 nm T-shaped gate, low ohmic contacts and a short drain-source distance, are integrated to gain high device performance. The fabricated InA1N/GaN HEMTs exhibit a maximum drain saturation current density of 1.65 A/ram at Vgs = 1 V and a maximum peak transconductance of 382 mS/rnm. In addition, a unity current gain cut-off frequency （fT） of 162 GHz and a maximum oscillation frequency （fmax） of 176 GHz are achieved on the devices with the 70 nm gate length.展开更多
We report high performance InA1N/GaN HEMTs grown on sapphire substrates. The lattice-matched InA1N/GaN HEMT sample showed a high 2DEG mobility of 1210 cmZ/（V.s） under a sheet density of 2.6 × 10^13 cm^-2. Large...We report high performance InA1N/GaN HEMTs grown on sapphire substrates. The lattice-matched InA1N/GaN HEMT sample showed a high 2DEG mobility of 1210 cmZ/（V.s） under a sheet density of 2.6 × 10^13 cm^-2. Large signal load-pull measurements for a （2 × 100 μm） x 0.25 μm device have been conducted with a drain voltage of 24 V at 10 GHz. The presented results confirm the high performances reachable by InAIN- based technology with an output power density of 4.69 W/ram, a linear gain of 11.8 dB and a peak power-added efficiency of 48%. This is the first report of high performance InA1N/GaN HEMTs in China's Mainland.展开更多
We report an enhancement-mode InA1N/GaN HEMT using a fluorine plasma treatment. The threshold voltage was measured to be ＋0.86 V by linear extrapolation from the transfer characteristics. The transconductance is 0 mS...We report an enhancement-mode InA1N/GaN HEMT using a fluorine plasma treatment. The threshold voltage was measured to be ＋0.86 V by linear extrapolation from the transfer characteristics. The transconductance is 0 mS/mm at Vc, s = 0 V and VDS = 5 V, which shows a truly normal-offstate. The gate leakage current density of the enhancement-mode device shows two orders of magnitude lower than that of the depletion-mode device. The transfer characteristics of the E-mode InA1N/GaN HEMT at room temperature and high temperature are reported. The current gain cut-off frequency （fT） and the maximum oscillation frequency （fmax） of the enhancement-mode device with a gate length of 0.3 #m were 29.4 GHz and 37.6 GHz respectively, which is comparable with the depletion-mode device. A classical 16 elements small-signal model was deduced to describe the parasitic and the intrinsic parameters of the device.展开更多
基金supported by the National Natural Science Foundation of China(No.61306113)
文摘InA1N/GaN high-electron mobility transistors （HEMTs） with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/A1/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF characteristics of the devices were measured. The fabricated devices show a maximum drain current density of 2.18 A/mm at VGs = 2 V, a low on-resistance （Ron） of 1.49 x2.mm and low gate leakage current. An excellent frequency response was also obtained. The current cut-off frequency （fT） is 81 GHz and the maximum oscillation frequency is 138 GHz, respectively.
基金Project supported by the National Natural Science Foundation of China(Nos.60890192,60876009)
文摘We report the DC and RF performance of InAlN/GaN high-electron mobility transistors with AlGaN back barrier grown on SiC substrates. These presented results confirm the high performance that is reachable by InAlN-based technology. The InAlN/GaN HEMT sample showed a high 2DEG mobility of 1550 cmE/（V-s） at a 2DEG density of 1.7 × 1013 cm-2. DC and RF measurements were performed on the unpassivated device with 0.2 μm ＂T＂ gate. The maximum drain current density at Vcs = 2 V is close to 1.05 A/mm in a reproducible way. The reduction in gate leakage current helps to increase the frequency performance of AlGaN back barrier devices. The power gain cut-off frequency of a transistor with an A1GaN back barrier is 105 GHz, which is much higher than that of the device without an A1GaN back barrier at the same gate length. These results indicate InAlN/GaN HEMT is a promising candidate for millimeter-wave application.
基金Project supported by the National Basic Research Program of China(No.2012CB619306)
文摘InA1N has been studied by means of temperature-dependent time-integrated photoluminescence and time-resolved photoluminescence. The variation of PL peak energy did not follow the behavior predicted by Varshni formula, and a faster redshift with increasing temperature was observed. We used a model that took account of the thermal activation and thermal transfer of localized excitons to describe and explain the observed behavior. A good fitting to the experiment result is obtained. We believe the anomalous temperature dependence of PL peak energy shift can be attributed to the temperature-dependent redistribution of localized excitons induced by thermal activation and thermal transfer in the strongly localized states. V-shaped defects are thought to be a major factor causing the strong localized states in our ln0.153Al0.847N sample.
基金supported by the National Natural Science Foundation of China(No.61306113)
文摘lnA1N/GaN high-electron-mobility transistors （HEMTs） on SiC substrate were fabricated and character- ized. Several techniques, consisting of high electron density, 70 nm T-shaped gate, low ohmic contacts and a short drain-source distance, are integrated to gain high device performance. The fabricated InA1N/GaN HEMTs exhibit a maximum drain saturation current density of 1.65 A/ram at Vgs = 1 V and a maximum peak transconductance of 382 mS/rnm. In addition, a unity current gain cut-off frequency （fT） of 162 GHz and a maximum oscillation frequency （fmax） of 176 GHz are achieved on the devices with the 70 nm gate length.
基金Project supported by the National Natural Science Foundation of China(Nos.60890192,60876009).
文摘We report high performance InA1N/GaN HEMTs grown on sapphire substrates. The lattice-matched InA1N/GaN HEMT sample showed a high 2DEG mobility of 1210 cmZ/（V.s） under a sheet density of 2.6 × 10^13 cm^-2. Large signal load-pull measurements for a （2 × 100 μm） x 0.25 μm device have been conducted with a drain voltage of 24 V at 10 GHz. The presented results confirm the high performances reachable by InAIN- based technology with an output power density of 4.69 W/ram, a linear gain of 11.8 dB and a peak power-added efficiency of 48%. This is the first report of high performance InA1N/GaN HEMTs in China's Mainland.
文摘We report an enhancement-mode InA1N/GaN HEMT using a fluorine plasma treatment. The threshold voltage was measured to be ＋0.86 V by linear extrapolation from the transfer characteristics. The transconductance is 0 mS/mm at Vc, s = 0 V and VDS = 5 V, which shows a truly normal-offstate. The gate leakage current density of the enhancement-mode device shows two orders of magnitude lower than that of the depletion-mode device. The transfer characteristics of the E-mode InA1N/GaN HEMT at room temperature and high temperature are reported. The current gain cut-off frequency （fT） and the maximum oscillation frequency （fmax） of the enhancement-mode device with a gate length of 0.3 #m were 29.4 GHz and 37.6 GHz respectively, which is comparable with the depletion-mode device. A classical 16 elements small-signal model was deduced to describe the parasitic and the intrinsic parameters of the device.
