In　this　study,　fracture　tests　of　chip/underfill/chip　sandwiched　system　were　carried　out,　with　non-contact　and　non-destructive　digital　image　correlation　(DIC)　technique,　under　various　loading　angles　from　20°　to　90°　for　different　temperature　levels　of　25,　75　and　125°C　or　after　moisture　ageing　at　85°C/85%RH,　to　study　the　effects　of　loading　angle,　temperature　and　moisture　on　the　interface　fracture　toughness.　With　the　results,　the　mode　I　and　mode　II　critical　fracture　toughness　based　failure　assessment　diagrams　(FADs)　were　established　for　reliability　design　and　failure　assessment　of　underfill/chip　interface　at　different　thermal　cycling　loading　and　moisture　conditions.　©　2006　IEEE.