DISLOCATION SCATTERING-LIMITED ELECTRON MOBILITY IN WURTZITE n-TYPE GALLIUM NITRIDE

The dislocation scattering-limited electron mobility (mu(dis)) for wurtzite GaN was analytically calculated as a function of both temperature and carrier concentration. The calculated results indicated that mu(dis) increases slightly by increasing the temperature in the range from 100-400 K. Moreover, as the dislocation density per unit area increases, mu(dis) is lowered particularly at low temperatures. Calculation of the mobility as a function of carrier concentration at constant temperature showed that the dislocation limited mobility grows up when the carrier concentration increases. A large change of mu(dis) was noticed by varying the fraction of the filled traps. The electron drift mobility was calculated considering many scattering centers, including the dislocation scattering mechanism. The results were compared with experimental data and it was found an agreement between the calculated electron mobility including dislocations with the experimental results particularly at low temperatures.