An effective solution to optimize the saddle-shape warpage in 3D IC applications by patterning laser treatment

Abstract The asymmetric saddle-shape warpage is one of the hardest limitations on the development of three-dimensional integrated circuits (3D ICs) as the vertical integration increases. To improve the product yield, an effective method for saddle-shape warpage reduction in 3D IC production by backside patterning laser annealing treatment with a multilayer structure is investigated in this work. The reduction of saddle-shaped warpage by patterning laser treatment is the first time in 3D NAND array wafer application and through simulations and experiments, the laser annealing pattern is determined. In addition, the materials of the multilayer structure are selected as amorphous Al 2 O 3 and TiN according to experiments and theoretical analysis. As a result, a conformal 47.8 µ m optimization of the saddle-shape warpage is successfully reached in a control wafer test by patterning laser annealing treatment.