Minority electron mobility in a p-n GaN photodetector
Photoconductive transients and responsivity in a GaN p-n UV photodetector under different applied voltages are investigated at room temperature. The electron mobility of minority carriers in the p-GaN epilayer has been measured by a diffusion time-of-flight technique, and was found to be about 0.12 cm2 V-1 s-1 with the bias between 1 V and 12 V. The difference of the electron mobilities between the minority carriers in p-GaN and the majority carriers in n-GaN is explained by different scattering mechanisms. The neutral impurity and phonon scattering mechanisms dominate the minority electron mobility in p-GaN. The photoconductive responsivity increases nearly linearly at low voltage and saturates at about 10 V, corresponding to a saturation field of approximately 3.7×104 V cm-1. The implication of these results for applications of GaN UV detectors is also discussed.
Physics, Astronomy, and Materials Science
Guan, Z. P., J. Z. Li, G. Y. Zhang, S. X. Jin, and X. M. Ding. "Minority electron mobility in a pn GaN photodetector." Semiconductor science and technology 15, no. 1 (2000): 51.
Semiconductor Science and Technology