With the rapid development of the DC grid, the DC circuit breaker, especially the hybrid type, plays an essential role in the operation of the whole system. The 6-in IGCT with 12.5kA current cut-off capability is promising for the hybrid DC breaker. However, the further improvement of current cut-off capability is restricted by the comprehension of the failure mechanisms. Based on this, a new method for current distribution study in the 6-in IGCT is proposed with a special package. Inductance simulation with finite element method reveals that the stray inductance of the new structure is extremely similar to the traditional one. Finally the current distribution is obtained with this new structure. The results can not only reveal the commutating process clearly, but show that the pressure distribution in the 6-in IGCT tends to be uneven, leading to current crowding in high-pressure area due to low contact resistance.