Influence of Packaging Structure on Switch Performance of GaN HEMT Half-Bridge Circuits

Due to the high electron mobility, ultra-high switching speed and low on-state resistance, Gallium nitride based high electron mobility transistor (GaN HEMT) shows excellent high frequency switching performance. However, under the influence of packaging parasitic parameters, the GaN-based half-bridge circuit exists some problems, such as voltage overshoot, ringing, oscillatory false triggering, and severe switching loss and so on. In this paper, packaging structures, packaging parasitic parameters and high frequency switching performances of normally-off 600V/650V GaN E-HEMTs with TO-247, PQFN 8x8 and Embedded packaging structures are comparatively investigated. These results show that parasitic $L_{S} + L{DH-DP}$ is as low as 0.3nH and the switching loss is $56.5 \mu \mathrm{J}$ in embedded packaging at 400V/15A, which are reduced by 98.6% and 55% respectively compared with TO-247 sample due to the small package size. The turn on di/dt and turn off dv/dt of Embedded packaging are maximum of 2 A/ns and 52.6 V/ns. The results demonstrate that embedded packaging is advantageous in high frequency power converters.