We have measured W 4f7/2 core-level photoemission spectra from W(110) in the presence of Ni overlayers, from ∼0.2 to ∼3 monolayers. Interfacial core-level shifts associated with first-layer Ni phases have been identified: −230± 15 meV for the 1×1 pseudomorphic phase and −70± 7 meV for the 7×1 close-packed commensurate phase. At higher Ni coverages the interfacial core-level shift is −100 ± 10 m...

Pseudomorphic Ga12xInxN/GaN single heterostructures in the composition range 0,x,0.2 have been investigated by photoreflectance and photoluminescence spectroscopy. Strong Franz–Keldysh oscillations near the band gap of the ternary film are observed and attributed to a large constant piezoelectric field of up to 0.63 MV/cm. This allows an accurate determination of the electric field. A significa...

The local reactivity of thin pseudomorphic Pd overlayers on Au(111) and (100) single crystal surfaces has been studied by periodic density functional theory calculations within the generalized gradient approximation. We have determined the adsorption energies of atomic hydrogen and of CO as a microscopic probe of the reactivity. We demonstrate that both surface strain effects and substrate inte...

In spite of their outstanding transport characteristics, InP high-electron mobility transistors (HEMT’s) deliver lower output power than GaAs pseudomorphic HEMT’s (PHEMT’s) throughout most of the millimeter-wave regime. However, the superior power-added efficiency of InP HEMT’s when compared with GaAs PHEMT’s makes this technology attractive for many applications. The reason for the relatively ...

This paper presents the design and simulation of a 2.4 GHz ISM band front end single stage Low Noise Amplifier (LNA) for wireless transceiver system. This amplifier uses AVAGO ATF-54143 transistor which is a low noise and high dynamic range Pseudomorphic high electron mobility transistor. The proposed method is addressed to optimize noise performance and power efficient while maintaining good i...

High electron mobility transistors (HEMTs) based on III–V semiconductor materials have been investigated as these devices are scaled down to gate lengths of 120, 90, 70, 50 and 30 nm. A standard Monte Carlo (MC) method coupled with the solution of Poisson’s equation is employed to simulate a particle transport. The average particle velocity and the field–momentum relaxation time are studied in ...

<span lang="EN-US">This paper presents the design of a pseudomorphic high electron mobility transistor (pHEMT) self-oscillating mixer (SOM) for millimeter wave wireless communication systems. The 180° out-of-phase technique is chosen to both improve desired lower sideband (LSB) signal and achieve satisfactory rejection unwanted signals (LO, USB IF). This SOM designed on PH15 process UMS f...