Application Note for Leica EM RES102 - In most cases, multi-layer structures or material combinations with large differences in hardness cannot be processed with conventional polishing techniques, or can only be very poorly processed. Due to the large differences in hardness, blurring or edge-rounding occurs, which distorts the original structure. In the application example shown, we are dealing with a solder ball structure. The goal was to determine the solder structure. The use of conventional grinding and polishing techniques was not possible due to the large differences in hardness between the solder ball and other materials in the sample.