High Current (1225A) Optical Triggering of 18-kV 4H-SiC Thyristor in Purely Inductive Load Circuit

Optical switch-on of a very high voltage (18-kV class) 4H-SiC thyristor with an amplification step (pilot thyristor) to the current Imax = 1225A has been demonstrated using a purely inductive load. The results obtained show that a further switch-on current increase can only be achieved by introducing additional amplification steps in the pilot thyristor structure.

Optical Triggering of High Current (1300 A), High-Voltage (12 kV) 4H-SiC Thyristor

A 12 kV class 4H-SiC thyristor with a pilot thyristor (an amplification step) has been triggered to a current Imax = 1310 A in a mixed resistive-inductive load circuit. In order to further increase the Imax, the homogeneity of the initially turned-on region should be improved and/or additional amplification steps introduced

Optical Triggering of 12 kV 1 cm2 4H-SiC Thyristors

We report on switch-on of 12 kV, 1cm2 optically triggered 4H-SiC thyristor fabricated by CREE Inc., to Imax=270 А with current rise time of ~ 3 s. Temperature dependence of holding current Ih in this thyristor has been experimentally studied in the temperature range from 300 to 425 K. It is shown that measurements of Ih temperature dependence under condition of optical switch-on at small anode bias and large load resistance reveal the existence of a ”weak point” within the optical window. This point is characterized by a much smaller critical charge than that within the remaining part of the window.