3D IC and stacked die configurations are often difficult to image with an acoustic microscope because the multiple internal surfaces send back so many echoes and re-echoes from the ultrasound pulsed into the stack. Stacked die makers wanting to check nondestructively for delaminations between layers have often been frustrated by this limitation.

Sonoscan (www.sonoscan.com) has now 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. The imaging parameters are then easily transferred to the Gen6 Sonolytics™ software and used to image the physical 3D IC or die stack.

In a short time the best gate positions and other parameters for imaging the physical 3D IC or die stack can be obtained, even by less experienced operators.