The invention belongs to the technical field of power semiconductors, and specifically relates to an SOI LIGBT with a controllable collector trough. Compared with a conventional structure, the LIGBT mainly introduces a controllable collector trough structure to a collector end and introduces a plurality of trough grid structures to the collector. During the forwarding conduction, the bias
voltage of a trough collector relative to the collector is negative, and a side wall of the collector trough forms a high-density P-type reflection layer so as to increase the hole implantation. The segmented trough grid structures serve as the blocking
layers of hole extraction. Therefore, the increase of the hole /
electron concentration in a drift region facilitates the obtaining of a lower forwarding conduction
voltage drop. Meanwhile, because an N+ collector region is located on the upper surface of a P+ collector region and does not make contact with an N-type drift region, a
new device does not has a
voltage turning-back effect. The beneficial effects of the invention are that the LIGBT, compared with a conventional short-circuit
anode-LIGBT structure, is higher in switching-off speed and lower in forwarding conduction
voltage drop, and does not have the voltage turning-back effect.