A novel E-mode AlGaN/GaN HEMT with double-doped p-gate (DDP) is proposed to improve output current and verified by TCAD simulation. The heavily p-doped region of the AlGaN gate layer ensures enhancement-mode (E-mode) operation and the lightly p-doped region of the AlGaN gate layer reduces the channel resistance. The simulated results have demonstrated that DDP HEMT delivers a much larger maximum drain current (IMAX = 334 mA/mm) than the conventional p-gate (CP) HEMT (IMAX = 144 mA/mm) while maintaining a high threshold voltage (VTH ~1.5 V). The simulated results also indicate that the DDP gate structure could decrease the peak electric field (EC) and thus improve the reliability of the device under off-state high-drain-bias (HDBT).
The influence of the moving on the radiation characteristics is an important research direction on the field of the
microwave remote sense. This paper has investigated the influence of the aerodynamic heating effect caused by high-speed
moving on the radiation property of the typical plane. Firstly, the temperature distributions on the plane skin under different
flight speeds have been calculated through Fluent simulation. Secondly, the emissivity of the skin under different
observation angles has been calculated by the method of equivalent transmission lines. Finally, the radiation brightness
temperatures of the stealth plane and the background have been calculated based on the blackbody radiation law and the
atmospheric radiation transfer model. The results show that the high-speed moving has a significant influence on the
radiation characteristic of the stealth target.
A new planar MISHEMT structure is proposed with the drain surrounded (D-S) by the gate channel. The gate channel serves as the stop-ring of the drain voltage, eliminating the damages from the high voltage on the mesa edge and isolation area. As a result, the leakage of the D-S MISHEMT is found to be reduced by almost 3 orders comparing with the source surrounded (S-S) MISHEMT. A saturated output current density of 740 mA/mm and an ON-resistance of 13.09 Ω-mm are obtained for device with LG/LGS/LGD/WC = 1.5/5/20/250 μm. Meanwhile, the degradation of dynamic ON-resistance and off-state breakdown performance are investigated in both D-S and S-S MISHEMT, which indicates excellent reliability of the D-S MISHEMT.
Zhang W, Zhang J, Shen M, Xiao N, Luo G. Mapping Large-Scale DNNs on Asymmetric FPGAs, in Proceedings of the 2018 ACM/SIGDA International Symposium on Field-Programmable Gate Arrays - FPGA '18. New York, New York, USA: ACM Press; 2018:291–291. 访问链接
The coating surface temperature of the stealth aircraft increases due to the motion and heating effect, which causes the inhomogeneous temperature distributions between the coating and the metal substrate. In this paper, the millimeter-wave radiation characteristics of the stealth aircraft under motion state are discussed. Firstly, one dimensional heat conduction equation of the stealth aircraft under motion state is established, and we obtain the temperature distributions along the vertical directions. Then, according to the layered coating and th e non-uniformity of diel ectric property caused by temperature variation, the total brightness temperature is calculated by using radiation transfer theory. The calculated results indicate that the temperature distributions of the motional aircraft coating varies with the t ime, and th e millimeter-wave radiation characteristics also have time-varying.