A new high resolution dispersive spectrometer has been developed to measure high pressure shock profiles every 10 ns using long Fiber Bragg Gratings. The performances are compared with a dynamic AWG-based spectrometer. Two small diameter fibers allow inserting in parallel two 50-mm long gratings into the target. The use of slightly chirped gratings provides the localization of the shock-wave along them. Placed along the target axis, a gratings reflected spectrum is "blue shifted". The FBG's central wavelength are 1605 nm to cover a pressure range of 0-8 GPa. The new spectrometer is based on a femtosecond laser source, a long dispersive fiber and a fast acquisition system with an electrical bandwidth above 30 GHz. The experimental setup was a symmetric impact with 6061T6 aluminum, performed with a 110-mm in diameter single-stage gas gun. An impact velocity of 314 m/s is obtained and generated a sustained level of 2.1 GPa during few microseconds. A resulted Bragg shift of (16 ± 1) nm is measured. The dispersive spectrometer offers much greater resolution than the AWG one which is favorable to retrieve more easily a pressure profile.

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In this paper, the electrical performance of double gate DG-MOSFET transistors in 4H-SiC and 6H-SiC technologies have been studied by BSIM3v3 model. In which the I–V and gm–V characteristics and subthreshold operation of the DGMOSFET have been investigated for two models (series and parallel) based on equivalent electronic circuits and the results so obtained are compared with the single gate SG-MOSFET, using 130 nm technology and OrCAD PSpice software. The electrical characterization of DG-MOSFETs transistors have shown that they operate under a low voltage less than 1.2 V and low power for both models like the SG-MOSFET transistor, especially the series DG-MOSFET transistor is characterized by an ultra low power. The different transistors are characterized by an ultra low OFF leakage current of pA order, very high ON/OFF ratio of and high subthreshold slope of order 0.1 V/dec for the transistors in 6H-SiC and 4H-SiC respectively. These transistors also proved higher transconductance efficiency, especially the parallel DG-MOSFET transistor.

Silicon carbide is a very interesting semiconductor for applications in high temperature, high frequency and high power. In this article, we have studied and compared MOS transistors with 130nm silicon carbide (3C-SiC, 4H-SiC and 6H-SiC) technologies using BSIM3v3 model. To perform this work we have used PSpice to study the characteristics I(V) and the transconductance gm as a function of temperature in the range -200° C to 750° C with a supply voltage VDS = 1.2V. We have also calculated the transition frequencies fT of the three types of transistors. Our results show that the (3C, 4H and 6H)-SiC transistors operate under a low voltage, low power, high temperature and high frequency in submicron dimension.