Characterization of ion-implanted InxGa1−xAs/GaAs 0.25 μm gate metal semiconductor field-effect transistors with F t≳100 GHz

Abstract

This work presents millimeter wave performance achieved by ion-implanted InGaAs/GaAs metal semiconductor field-effect transistor devices. A current gain cutoff frequency ft of 126 GHz and maximum frequency of oscillation fmax of 232 GHz have been measured for 0.20 μm gate length devices. The ft and low-field Hall mobility data, measured at 300 and 112 K, lead us to conclude that the average electron velocity under the gate is mainly due to the high-field velocity rather than low-field electron mobility.

Structural, Electronic, and Optical Properties of InxGa1-xAs Alloys by Full Potential Linear Augmented Plane Wave Method

“…In recent years, it has been established that In x Ga 1Àx As is very useful for high-frequency and high-speed device applications 1) because of the large energy separation between À and Ł symmetry points. For low indium concentrations (x 0:18), a thick layer of In x Ga 1Àx As on a GaAs substrate improves Schottky gate barrier height, leading to a reduction in leakage current.…”

“…For low indium concentrations (x 0:18), a thick layer of In x Ga 1Àx As on a GaAs substrate improves Schottky gate barrier height, leading to a reduction in leakage current. 1) The In x Ga 1Àx As alloy on a InP substrate for 0:30 x 0:70 is useful for photoconductive switches, 2) long-wave optical modulators. 3) Metallorganic molecular beam epitaxy (MOMBE) 4) is a widely accepted growth technique for successful synthesis of semiconducting alloys.…”

“…A tremendous effort have been made to understand In x Ga 1Àx As structured devices. [1][2][3]5,6) There is a great advantage in controlling the physical properties of the alloys In x Ga 1Àx As by changing In concentration ðxÞ. It is important to note that InAs 7) as well as GaAs 8) are direct band gap semiconductors.…”

“…The optical and electronic properties of InAs and GaAs are well studied. [1][2][3][5][6][7][8] Kim et al 15) have used model calculations to obtain critical points as a continuous function of ðxÞ. We are not aware of any systematic theoretical study of the dielectric function and critical point (CP) energies for In x Ga 1Àx As alloys.…”

“…The generalized gradient approximation (GGA) is used for the exchange and correlation potentials. 10) In the calculations, we choose the following valence states: 4s 2 , 4p 1 for Ga; 4s 2 , 4p 3 for As; and 5s 2 , 5p 1 for In. The R MT 's are kept constant throughout the calculations, i.e., 2.2, 2.2, and 2.3 a.u.…”