Precise Downsizing of a <100 µm Thin Die Out of a Package Prior to Delayering

The delayering process is important in preparing thin dice that have been removed from their packages. These thin dice are frequently used for fault isolation and failure analysis. The size of the sample must be decreased for a precise delayering. This downsizing before the polishing process will reduce edge rounding and increase control of the planar polishing. It is also crucial to center the area of interest before polishing since this the success rate is higher for targets at the center of the sample compared with targets on the edge. Small samples with surface areas below 10mm2 and thicknesses under 100 μm need to be handled carefully. There is a risk of chipping and losing the area of interest.

LatticeAx Indent and Cleaving System

As a case study, a fabless semiconductor company contacted LatticeGear about improving the efficiency and speed of their sawing and hand cleaving process. Their method of choice is now the LatticeAx indent and cleaving system (Figure 1). The position of the diamond wedge indenter can be precisely controlled, allowing the user to exactly choose the location of the cleave. The indenter is then lowered onto the sample and creates a defect on the surface that will cause a cleave to propagate (Figures 2 and 3). This method will result in a high-quality sample and does not damage the edges (Figure 4).

Figure 1. LatticeAx indent and cleaving system.

Figure 2. Diamond wedge indenter close to the sample surface.

Figure 3. Left. Sketch of wedge indenter separating the sample Right. Sample downsized using the LatticeAx.

Figure 4. Top. Thin sample after downsizing using sawing. Bottom. Thin sample after cleaving with the LatticeAx

This information has been sourced, reviewed and adapted from materials provided by LatticeGear.

For more information on this source, please visit LatticeGear.