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The performance of novel AlInN/GaN HEMTs for high power / high temperature applications is discussed. With 0.25 mum gate length the highest maximum output current density of more than 2 A/mm at room temperature and more than 3 A/mm at 77 K have been obtained even with sapphire substrates. Cut-off frequencies were f<sub>T</sub> = 50 GHz and f<sub>MAX</sub> =(More)
The kink effect in InAlAs/InGaAs/InP composite channel heterojunction field effect transistors (HFETs) was investigated as a function of temperature and optical excitation. Drain source and gate current measurements show that above 325 K the kink effect disappears while the impact ionization process is still present. The kink at low temperatures is(More)
InAlN/GaN is indeed an alternative to the common AlGaN/GaN heterostructure in electronics and sensing. It enables operation at extremely high temperature once problems with contact metallization and passivation have been solved. It is the only heterostructure known presently, which allows overgrowth of high quality diamond films to combine two of the most(More)
In this study we have investigated heterojunctions on sapphire with barrier thicknesses between 13 nm and 5 nm maintaining a high output current. The results indicate that InAlN/GaN HEMT device structures can be reliably designed and fabricated with barrier layer thicknesses approaching the tunnelling thickness and approaching enhancement mode(More)
We discuss the characteristics of high-electron mobility transistors with barrier thicknesses between 33 and 3 nm, which are grown on sapphire substrates by metal-organic chemical vapor deposition. The maximum drain current (at V<sub>G</sub> = 2.0 V) decreased with decreasing barrier thickness due to the gate forward drive limitation and residual(More)
The impact of hole confinement on low frequency noise in SiGe pMOSFETs is investigated. The relative spectral power density of low frequency (l/j) noise in SiGe pMOSFETs is found .to be significantly lower than in Si devices produced with the same technology. This is mainly attributed to the physical separation of the holes confined in the SiGe channel from(More)
Modulation-doped GaAs/In<inf>0.25</inf>Ga<inf>0.75</inf>As/Al<inf>0.3</inf>Ga<inf>0.7</inf> As HEMT structures were grown using different MBE-growth temperatures and In<inf>0.25</inf>Ga<inf>0.75</inf>As channel thicknesses. Drain current DLTS measurements performed on these samples using a Fourier-Transform technique show that the concentrations of both(More)
An original method for the extraction of FET parameters at low drain bias is presented. It is based on a simple linear charge-control model and on a power-law dependence (with an exponent k &#x226B; 0 for GaAs/AIGaAs MODFET's and k &#x226A; 0 for Si-MOSFET's) of the low-field mobility &#x003BC; on the two-dimensional electron gas (2DEG) concentration(More)
In this paper, the properties of 5 nm barrier HEMT devices has been investigated in a temperature ramping experiment as used for AlGaN/GaN devices. The pinch-off voltage remains identical and the Schottky diode leakage only marginally increased. The ohmic contacts, which have been alloyed at 850 degC by RTA show also exceptional stability. The initial(More)
We studied the influence of the growth temperature T<inf>s</inf> and of the InGaAs quantum-well channel thickness d<inf>ch</inf> on the 300 and 77 K Hall electrical properties of pseudomorphic MODFET-type heterostructures grown by molecular-beam epitaxy (MBE). In agreement with Nguyen et al., we find an optimum channel thickness of 90 A for an indium(More)