High Temperature Electrical Conductivity of Aluminum Nitride.

摘要

The electrical conductivity of high purity (99.8 pct) AlN has been determined using both a-c and d-c techniques. Measurements were made at temperatures between 700 and 1000 C and in a nitrogen pressure range of 1 to .001 atm. The electrical conductivity is independent of nitrogen pressure. Galvanic cell results indicate that ionic conduction is negligible. Over the experimental temperature range, the electrical conductivity of AlN follows the equation sigma (1/(ohm cm) = 6890 exp (-E/kT) where the activation energy (E) is 1.82 + or - 0.06 eV. It is concluded that the conduction process is extrinsic due to carbon impurities (about 350 ppm) present in the AlN. (Author)