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School of ECE, Georgia Tech, Atlanta, GA 30332, [email protected] ** Dept. of ECE, University of Minnesota, Minneapolis, MN 55455 Cite this article as: MRS Internet J. Nitride Semicond. Res. 4S1, G6.59 (1999) ABSTRACT Ensemble Monte Carlo calculations of electron transport at high applied electric field strengths in bulk, wurtzite phase InN are presented. The calculations are performed using a full band Monte Carlo simulation that includes a pseudopotential band structure, all of the relevant phonon scattering agents, and numerically derived impact ionization transition rates. The full details of the first five conduction bands, which extend in energy to about 8 eV above the conduction band minimum, are included in the simulation. The electron initiated impact ionization coefficients and quantum yield are calculated using the full band Monte Carlo model. Comparison is made to previous calculations for bulk GaN and ZnS. It is found that owing to the narrower band gap in InN, a lower breakdown field exists than in either GaN or ZnS. INTRODUCTION Wide band-gap semiconductors are becoming of increasing importance in many emerging optoelectronic and electronic device applications. Among these applications are ultraviolet (UV) photodetectors, blue and UV light emitters, and high frequency, high power electronic devices. Of the emerging wide band-gap semiconductors, the most promising candidates for power field effect transistors, FETs, are SiC and the Ill-nitrides. It is well known that SiC or GaN based transistors offer significantly higher maximum output power than comparable structures made from GaAs or Si [ 1,2]. Owing to their relatively wide and direct energy band-gap, the III-nitride semiconductors are in addition particularly useful for UV and blue-light photonic detectors and emitters. The Ill-nitrides offer an additional advantage since heterostructures can be made from these materials. Along with GaN, the InN ternary alloy, InGaN, has found application in a variety of heterostructure based opto-electronic devices. In spite of its potential application, little information is available about the transport properties of InGaN or its constituent binary materials, InN and GaN. Some progress has been made on GaN [3-10], but only a single limited study of electron transport in InN [I I ] has yet been performed. It is the purpose of this paper to present the first theoretical study of the high field electronic transport properties of bulk InN. The calculations are performed using a full band, ensemble Monte Carlo simulation that includes a numerical formulation of the interband impact ionization transition rate [12]. The electron initiated impact ionization coefficients are calculated as a function of applied electric field strength.

G 6.59 Mat. Res. Soc. Symp. Proc. Vol. 537 © 1999 Materials Research Society

MODEL DESCRIPTION The band structure of InN used within the Monte Carlo simulation is calculated using the empirical pseudopotential method. Though ab initio methods have been applied to the study of InN