Transport and Mobility Properties of Bulk Indium Nitride (InN) and a Two-Dimensional Electron Gas in an InGaN/GaN Quantum Well Z. YARAR, 1,3 B. OZDEMIR, 2 and M. OZDEMIR 2 1.—Department of Physics, Faculty of Arts and Sciences, Mersin University, C ¸ iftlikko ¨y 33343 Mersin Turkey. 2.—Department of Physics, Cukurova University, Adana 01330 , Turkey. 3.—e-mail: zyarar@mersin.edu.tr We studied the transport and low-field mobility properties of bulk InN and a two-dimensional electron gas confined in an InGaN/GaN quantum well with regard to various parameters such as well width and interface roughness as a function of temperature. Since new material parameters for InN have been suggested by recent studies, the traditionally accepted and recently published parameter values for InN are used in our simulations and the results are compared. Mobility values in two and three dimensions are found from the steady-state drift velocities of carriers calculated using an ensemble Monte Carlo technique. Electron transport properties of bulk GaN and AlN are also presented and compared with bulk InN and InGaN/GaN quantum wells. The mobility of carriers in two dimensions is about 10,000 cm 2 /V s for low tem- peratures and in bulk InN increases significantly to a value of about 6,450 cm 2 /V s at room temperature when recently established material parameters are used. Key words: Scattering, Monte Carlo, InGaN/GaN, InN, GaN, AlN, quantum well, Schro ¨dinger–Poisson, drift velocity, mobility INTRODUCTION The III-nitride-based systems in general and InN in particular have attracted a great deal of attention in recent years. These materials had been known to have wide band-gap energies (3.42 eV for GaN, 6.2 eV for AlN, and 1.89 eV for InN) so that they can be used for the fabrication of devices working in the blue and ultraviolet regions of the spectrum. How- ever, there is controversy over the material parameters of InN and, according to recent studies, its band gap value is between 0.7 eV and 0.8 eV 1–6 with band-gap bowing of 1.43 eV. 4 In addition to the intriguing controversy about the fundamental band gap of InN, another undetermined important parameter is the effective mass m*. Effective mass plays a dominant role for transport and mobility characteristics and device design but various values have been reported for InN. The commonly used, traditional value for the effective mass is 0.11m 0 7 but for the band gap of 0.7–0.8 eV, the effective mass is presented as 0.07m 0 8 and in other studies as 0.042m 0 , 9–11 where m 0 is the free electron mass. A more-recent study even questions the validity of a band-gap value of about 0.7 eV. 12 Previously com- monly used parameter values for the band-gap en- ergy, band-gap bowing, and effective mass for InN were 1.89 eV, 13 3.8 eV, 14 and 0.11m 0 , 7 respectively. To our knowledge, there is no updated data for the material parameters for the case of InGaN alloys at present. The electron transport characteristics of InN have been studied 15–17 and during the past few years electron low-field mobilities in InN above 2000 cm 2 / V s have been measured. 18–21 The best reported mobility of InN at room temperature was about 3500 cm 2 /V s. 19 Recent theoretical estimates for low-field mobility with undoped InN have reached (Received December 2, 2006; accepted July 23, 2007; published online September 11, 2007) Journal of ELECTRONIC MATERIALS, Vol. 36, No. 10, 2007 Regular Issue Paper DOI: 10.1007/s11664-007-0210-9 Ó 2007 TMS 1303