Abstract
Low frequency noise in 6H-SiC ion implanted p-n diodes has been investigated. The noise measurements were performed under forward bias over a wide temperature range from 77 to 300 K and frequency range from 10 to 100 kHz. Three diodes with different areas A(1), A(2), and A(3), (A(1)<A(2)<A(3)), have been studied. The effect of the area on the noise properties of these junctions was found to be at room temperature, depending on the origin of the noise. Two relationships between the noise spectral density S-I(f) and the area (A) have been found to describe the noise behavior observed in these junctions at different current density ranges. From the noise experimental data at low temperatures, two different trap states were detected in the diode with the smallest area. This explains the higher noise level observed in this diode in the recombination-generation region. (C) 1999 American Institute of Physics. [S0021-8979(99)00709-4].