? ???????????????? InxGa1–xAs/GaAs ? ????????? ????????? ????? (??) ?????? ????????????? x ????? ?????????? ??????????? ???????????? ??????????. ??? ????-??????? ????????? ?? ???????? h\? = 1,2 ?? ????????? ??????? ???????????? ???????? ?????????? ?? ?????????? ??????????, ? ????? ????? ?????????? ??????????? ????? ????????? ?????????????? ??????????????. ?????? ????? ?? ?????????????????? (???...

Effects of d-doping on barriers effective heights and series resistance of highly doped n-type GaAs/AIAs/GaAs/AlAs/GaAs heterostructures, grown by molecular beam epitaxy (MBE) at 400?°C, have been studied. As it was expected, inclusion of an n+ d-doped layer at each hetero-interface has reduced the barriers heights and series resistance of the structure significantly, while p+ d-doped layers ha...

This work has as main objective the integration of planar Gunn diodes and high electron mobility transistors (HEMTs) on the same chip for the realisation of high-power oscillators in the millimeter-wave regime. By integrating the two devices, we can reinforce the high frequency oscillations generated by the diode using a transistor-based amplifier. The integration of the planar Gunn diode and t...

abstract the structural and electrostatic properties of the single-walled two representative (8, 0) zigzag and (4, 4) armchair models of pristine and gaas-doped on boron phosphide nanotubes (bpnts) was investigated by calculating the nuclear magnetic resonance tensors and with performing the density function theory. the geometrical structures of all representative pristine and gaas-doped models...

The need for both linear and efficient pseudomorphic high electron-mobility transistors (pHEMTs) for modern wireless handsets necessitates a thorough understanding of the origins of intermodulation distortion at the device level. For the first time, the dynamic large-signal internal physical behavior of a pHEMT is examined using a quasi-two-dimensional physical device model. The model accounts ...

In this paper we present coplanar MMICs based on both, metamorphic (MHEMT) and pseudomorphic (PHEMT) high electron mobility transistor technologies. Starting with a modulator-driver MMIC for optical transmission systems, we describe state of the art MMICs like a 94 GHz low-noise amplifier, a 35 GHz and a 60 GHz medium power amplifier and finally we demonstrate the feasibility of a monolithicall...

The properties of HBTs, HEMTs, PHEMTs and MESFETs are reviewed and discussed in the context of their suitability for various applications. Noise, power and high frequency performance is reviewed and the physical mechanisms dictating their values are discussed. The reliability characteristics of the devices are discussed and system applications are reported.

In this paper, the design of efficient transmitting architectures is addressed. Taking advantage of the modeling and characterization of novel active devices as GaN HEMT and E-pHEMT, several topologies have been approached. An outphasing transmitter at 770 MHz have been implemented from two class-E RFPA designed over package GaN HEMTs. In addition, for multiband applications, a dual band outpha...