Title :
Fracture mechanics analysis of the effect of geometry on delaminations in rectangular IC packages
Author :
Tay, A.A.O. ; Zhu, H.
Author_Institution :
Center for IC Failure Anal. & Reliabilty, Nat. Univ. of Singapore, Singapore
Abstract :
This paper describes a numerical study the effect of package geometry on delaminations in plastic IC packages. A comprehensive set of linear elastic, finite element fracture analyses were carried out on a TSSOP (Thin Shrink Small Outline Package) with outer dimensions 9.7 mm×4.4 mm×1 mm and die pad dimensions 5.5 mm×3 mm -0.125 mm. The virtual crack closure method was used to calculate the strain energy release rate (ERR) at the tip of a small crack at the edge of the pad-encapsulant interface. A parametric analysis was carried out. Among other things, it was found that the size of the border between the die and the die pad had the greatest influence on the ERR. If this border was greater than 0.8 mm the ERR became more or less independent of the length of the die. This finding should be very useful for packaging design
Keywords :
crack-edge stress field analysis; delamination; finite element analysis; fracture mechanics; integrated circuit packaging; plastic packaging; 0.125 mm; 1 mm; 3 mm; 4.4 mm; 5.5 mm; 9.7 mm; CTE mismatch; delaminations; finite element analysis; fracture mechanics analysis; geometry effect; linear elastic analysis; packaging design; pad-encapsulant interface; parametric analysis; plastic IC packages; rectangular IC packages; small crack tip; strain energy release rate; thin shrink small outline package; virtual crack closure method; Delamination; Finite element methods; Geometry; Integrated circuit packaging; Lead; Moisture; Plastic integrated circuit packaging; Temperature; Thermal expansion; Thermal stresses;
Conference_Titel :
Electronic Components and Technology Conference, 2001. Proceedings., 51st
Conference_Location :
Orlando, FL
Print_ISBN :
0-7803-7038-4
DOI :
10.1109/ECTC.2001.927793
