Multi-finger power SiGe HBTs with non-uniform Spacing

Based on a three-dimensional thermal-electrical model, non-uniform finger spacing power SiGe HBT was designed and fabricated. Experiment result shows that the peak temperature of non-uniform spacing SiGe HBT is Iowed by 22 K compared with that of uniform space HBT. For the same nonuniform spacing HBT, temperature non-uniformity among the fingers is improved obviously at different biases. The higher power dissipation P_DC is, the better temperature improvement of non-uniform spacing HBT is. Because of the reducing of peak temperature, power SiGe HBTs with non-uniform Spacing can work at higher bias and has higher power handling capability.