1/f noise in forward biased high voltage 4H-SiC Schottky diodes

•The 1/f noise in high-quality 4H-SiC Schottky diodes has been studied firstly.•At 300K, diodes demonstrate a “nearly ideal” behavior with ideality factor 1.03.•At 77K, I-V and noise characteristics manifest barrier height distribution.•At 77K, the 1/f noise is generated in the parts of low barrier height. The 1/f noise has been investigated for the first time at 300 and 77K in high-quality 4H-SiC Schottky diodes. It is shown that, at 77K, the dependence of the spectral noise density on current, SI(I), differs fundamentally between the cases of the current flowing through the main part of the diode with a comparatively high barrier and the current flowing through the nano-sized patches with a comparatively low barrier.