LESECQ , Marie

Despite the fact that a lower growth temperature is generally considered as a drawback for achieving high crystal quality, the necessity to reduce the nucleation temperature of AlN on Silicon has permitted Molecular Beam Epitaxy (MBE) to demonstrate high performance for GaN transistors operating at high frequency. Compared to Metal-Organic...

Despite a lower growth temperature is generally considered as a drawback for achieving high crystal quality, the necessity to reduce the nucleation temperature of AlN on Silicon has permitted Molecular Beam Epitaxy (MBE) to demonstrate high performance for GaN transistors operating at high frequency. Compared to Metal-Organic Vapor Phase...

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The onset and pinch-off voltages shift of lateral GaN field-effect rectifier diodes (L-FER) and normally-off HEMTs are studied. It is shown that a short duration of low power SF6 plasma followed by a low temperature annealing permits to get an effective and stabilized fluorine ion implantation in the AlGaN barrier, contributing to reduce the...

This paper reports on the fabrication and characterization of AlGaN/GaN HEMTs transfered onto two different adhesive flexible tapes. Technological improvements were made during the study concerning thermal conductivity of the tapes as well as the transfer process. In this paper, it is shown that the device transferred onto the tape with higher...

In this work, the electrical properties of ScAlN/GaN high electron mobility transistor (HEMT) heterostructures grown by ammonia source molecular beam epitaxy are studied. The effect of growth temperature and ScAlN barrier thickness on 2DEG carrier density is investigated with capacitance-voltage measurements. Alloyed ohmic contacts have been...

Transfer technology is now becoming very attractive not only for new technologies such as flexible technology but also for solid state technologies when performances are limited by technological barriers that have to be overcome. In this last context, the transfer of high electron mobility transistors (HEMTs) on diamond substrates represents an...

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In this letter, a record performance at 40 GHz obtained on AlGaN/GaN high electron mobility transistor (HEMT) grown on Hydride Vapor Phase Epitaxy (HVPE) Free-Standing GaN substrate is reported. An output power density of 2 W.mm-1 associated with 20.5 % power added efficiency and a linear power gain (Gp) of 4.2 dB is demonstrated for 70 nm gate...

Schottky contacts on fluorine implanted AlGaN/GaN heterostructures with the ideality factor close to unity and low on-voltage threshold are presented in this paper. An SF 6 plasma anode pretreatment followed by a specific low-temperature annealing is also compared to a nonannealed sample. In addition, physical-model parameters are extracted by...

Blue (Ga,In)N-based light-emitting diodes (LEDs) grown on a Si(111) substrate by metal-organic vapor phase epitaxy are transferred on a flexible tape after the Si substrate removal. Their optical and thermal behaviors are measured and compared to those of regular LEDs on Si. The light output power of the flexible LEDs is increased due to a...

This letter reports on the first demonstration of microwave power performance at 10 GHz on flexible AlGaN/GaN high-electron-mobility transistor (HEMT). A maximum dc current density of 620 mA/mm at V-GS = 0 V and a peak extrinsic transconductance of 293 mS/mm are obtained for a 2 x 50 x 0.1 mu m(2) flexible device. At V-DS = 5 V, a...

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This paper reports on the kink effect observed in InAlN/GaN high electron mobility transistors. Electrical characterizations were carried out to point out the influence of this phenomenon on transistor behaviour. It is demonstrated that the kink effect is directly correlated to shallow traps located under the conduction band. A model is...

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The role that the mother substrate plays to influence the performance of InGaN/GaN-based light-emitting diodes (LEDs) onto the adhesive flexible tapes is addressed in this letter. For this purpose, the electroluminescent (EL) spectra and current density-voltage (J-V) characteristics of flexi-LEDs are studied under different convex bending...

AlN nucleation layer is the key issue for the performance of GaN high frequency telecommunication and power switching systems fabricated after heteroepitaxy on Silicon or Silicon Carbide. In this work, we demonstrate and explain both the low level and the origin of propagation losses in GaN/3C–SiC/Si High Electron Mobility Transistors (HEMTs)...

This letter reports on the demonstration of microwave power performance at 40 GHz on AlGaN/GaN high-electron mobility transistor grown on silicon (111) substrate by molecular beam epitaxy. A maximum dc current density of 1.1 A.mm(-1) and a peak extrinsic transconductance of 374 mS.mm(-1) are obtained for 75-nm gate length device. At V-DS = 25...

In this work, an AlGaN/GaN HEMT structure is grown on a 0.8 μm thick 3C-SiC layer on high resistivity Silicon substrate. The RF propagation losses are investigated and compared with the ones of epi-layers grown directly on Silicon and on 6H-SiC substrates. Short gate length transistors are fabricated using e-beam lithography. In spite of ohmic...

Herein, the interest of cubic silicon carbide as a template for the growth of AlGaN/ GaN high electron mobility transistor (HEMT) heterostructures on silicon substrates for high-frequency operation is shown. On the one hand, 0.6-0.8 μm-thick 3C-SiC grown by chemical vapor deposition on intrinsic silicon substrate having initial resistivity...

International audience

Herein, the interest of cubic silicon carbide as a template for the growth of AlGaN/ GaN high electron mobility transistor (HEMT) heterostructures on silicon substrates for high-frequency operation is shown. On the one hand, 0.6-0.8 μm-thick 3C-SiC grown by chemical vapor deposition on intrinsic silicon substrate having initial resistivity...

This work aims to understand the origin of propagation losses in GaN-on-Si devices at microwave frequencies thanks to original AFM's electrical modes such as scanning capacitance microscopy (SCM) and scanning spreading resistance microscopy (SSRM). AlN films on Si substrate were grown using Metalorganic Vapor Phase Epitaxy (MOVPE) technique....