Group-III Nitrides Hot Electron Effects in Moderate Electric Fields

Abstract

We studied the distribution function and basic characteristics of hot electrons in InN, GaN and AlN under moderate electric fields, and found that in relatively low fields (of the order of kV/cm) the optical phonon emission dominates the electron kinetics. This strongly inelastic process gives rise to a spindle-shaped distribution function and an extended portion of quasi-saturation of the current-voltage characteristics (the streaming-like regime). We prove that this hot electron regime holds for all three nitrides. We suggest that the effects can be detected by the measurement of the I -V characteristics, or the thermopower of hot electrons in the transverse direction.Introduction Recent intensive studies of the electron kinetics in group-III nitride materials are mostly focused on two subjects: the problem of the low-field mobility and the problem of the peak (saturation) velocity in extremely high electric fields (hundreds of V/cm, see Refs. [1][2][3][4][5]). Meanwhile, such basic properties of the nitrides such as relatively low effective masses, high optical phonon energies, strong electron-optical phonon interaction and large energy separations of the upper valleys bring about a number of new hot electron effects in moderate electric fields. These effects can be of interest for both the understanding of fundamentals of the electron kinetics in the nitrides and their applications. This paper addresses the hot electron kinetics in group-III nitrides at moderate electric fields.

Streaming distribution of two-dimensional electrons in III-N heterostructures for electrically pumped terahertz generation

“…This opens prospects for realization of the streaming regime and its applications at or above the nitrogen temperature. Indeed, recent studies 6,7 have shown that in bulk III-N materials, a strongly anisotropic electron distribution can occur, and the pronounced OPTT resonance as well as the THz generation can be achieved at moderate electric fields.…”

Phase-plane analysis and classification of transient regimes for high-field electron transport in nitride semiconductors

“…(15), which depends only on the nonparabolicity parameter c . Mathematically, of special note is the very simple form of Eq.…”

“…[6][7][8][9][10][11][12][13][14][15] Two main approaches were undertaken. [6][7][8][9][10][11][12][13][14][15] Two main approaches were undertaken.…”