Carrier mobility distribution in annealed undoped LEC InP material

N-type liquid encapsulated Czochralski (LEC) undoped InP wafers are anneale d between 700 and 900 degrees C for different durations. From a large quant ity of Hall measurement results, it is found that there is a Hall mobility distribution dependent on the carrier concentration of the annealed materia l. The lowest mobility is observed in the samples with concentration around similar to 10(10) cm(-3). In these samples carrier mobility increases with increasing temperature which is caused by nonuniformity. Combined with res ults of defect investigation in the annealed material, formation of defects and their nonuniform distribution are found to correlate with this mobilit y distribution. The formation of defect complexes is interpreted as a reaso n for the high mobility observed in annealed InP. (C) 2000 Elsevier Science B.V. All rights reserved.