1.Scientific and Social Benefits of DNA Barcoding Along with the accelerated global trade and climate change,the needs for sustainable development and for understanding biodiversity are increasing.Rapid and accurate s...1.Scientific and Social Benefits of DNA Barcoding Along with the accelerated global trade and climate change,the needs for sustainable development and for understanding biodiversity are increasing.Rapid and accurate species identification and sustainable utility of biodiversity resources have become a great need for the world.展开更多
We studied the performance of AlGaN/GaN double heterojunction high electron mobility transistors (DH-HEMTs) with an AlGaN buffer layer, which leads to a higher potential barrier at the backside of the two- dimension...We studied the performance of AlGaN/GaN double heterojunction high electron mobility transistors (DH-HEMTs) with an AlGaN buffer layer, which leads to a higher potential barrier at the backside of the two- dimensional electron gas channel and better carrier confinement. This, remarkably, reduces the drain leakage current and improves the device breakdown voltage. The breakdown voltage of AlGaN/GaN double heterojunction HEMTs (-100 V) was significantly improved compared to that of conventional AlGaN/GaN HEMTs (-50 V) for the device with gate dimensions of 0.5 - 100μm and a gate-drain distance of 1μm. The DH-HEMTs also demonstrated a maximum output power of 7.78 W/mm, a maximum power-added efficiency of 62.3% and a linear gain of 23 dB at the drain supply voltage of 35 V at 4 GHz.展开更多
文摘1.Scientific and Social Benefits of DNA Barcoding Along with the accelerated global trade and climate change,the needs for sustainable development and for understanding biodiversity are increasing.Rapid and accurate species identification and sustainable utility of biodiversity resources have become a great need for the world.
基金Project Supported by the National science and Technology Major Project of thc Ministry of Science and Technology of China(No. 2008ZX01002-002)the Major Program and the Key Program of the National Natural science Foundation of China(Nos.60890191, 60736033)
文摘We studied the performance of AlGaN/GaN double heterojunction high electron mobility transistors (DH-HEMTs) with an AlGaN buffer layer, which leads to a higher potential barrier at the backside of the two- dimensional electron gas channel and better carrier confinement. This, remarkably, reduces the drain leakage current and improves the device breakdown voltage. The breakdown voltage of AlGaN/GaN double heterojunction HEMTs (-100 V) was significantly improved compared to that of conventional AlGaN/GaN HEMTs (-50 V) for the device with gate dimensions of 0.5 - 100μm and a gate-drain distance of 1μm. The DH-HEMTs also demonstrated a maximum output power of 7.78 W/mm, a maximum power-added efficiency of 62.3% and a linear gain of 23 dB at the drain supply voltage of 35 V at 4 GHz.