3D IC and stacked die configurations are often difficult to image with an acoustic microscope as the multiple internal surfaces send back so many echoes from the ultrasound pulsed into the stack. Stacked die makers wanting to nondestructively check for de-laminations between layers have often been frustrated by this limitation.
Sonoscan has taken a major step toward resolving this problem with the introduction of its SonoSimulator software, which is now a standard feature on the Gen6 C-SAM acoustic microscope.
The SonoSimulator determines optimal gate positions and other parameters with far less effort than is possible with the physical stacked parts alone. It also results in higher quality acoustic images.
This powerful new software allows the operator to create a virtual die stack that matches the characteristics of the physical 3D IC or die stack to be inspected, including defects at specified layers. The virtual defects help determine the optimum placement of gates to image specific levels in the stack.