Backside sample preparation is required by many post silicon validation techniques like FIB (Focused Ion Beam) circuit editing and optical probing using Photon Emission or Laser Stimulus methods . In spite of many conventional methods of silicon thinning and polishing, some challenges remain as new packages are introduced. With large die packages the issue of cracking during backside thinning is arising due to package curvature stress. 3D profile methods will be shown in conjunction with thermal relaxation to alleviate silicon center to edge variance allowing sample prep of large areas with thicknesses below 10μm. Thinning and polishing methods will be shown to be interactive with the device heated; demonstrating both thermal stress reduction coupled with curvature reduction.