LOW-FREQUENCY NOISE IN 4H-SILICON CARBIDE JUNCTION FIELD-EFFECT TRANSISTORS

Low frequency noise in 4H-silicon carbide junction field effect transi stors (JFETs) has been investigated. JFETs with a buried p(+)n junctio n gate were manufactured by CREE Research Inc. Very low noise level ha s been observed in the JFETs. At 300 K the value of Hooge constant alp ha is as small as alpha similar to 10(-5) and the alpha value can be d ecreased by an appropriate annealing to alpha similar to 2 X 10(-6). I t has been shown that even these extremely low noise values are determ ined not by the volume noise sources but by the noise at the SiC-SiO2 interface. (C) 1996 American Institute of Physics.