Strength evaluation for the wire is very important to avoid crack generation at the selection of materials and the structural design of semiconductor packages.
This paper describes the strength evaluation for a wire with the copper-cored semiconduct...
Strength evaluation for the wire is very important to avoid crack generation at the selection of materials and the structural design of semiconductor packages.
This paper describes the strength evaluation for a wire with the copper-cored semiconductor package.
A simplified FEM(Finite Element Method) model targeting issues at the package structural design was developed and its validity was checked against a more elaborated FEM model.
From the FEM analysis of thermal stress induced by the difference of thermal expansion coefficients of the composite materials and the detection of crack generation during the thermal cyclic test, it has been proved that the point location where the maximum thermal stress appears coincides with the one where the crack occurs.
Through a series of FEM analysis, it has been proved that the cause of a crack is strongly related to the gap between the lid and the copper core and the suitable length of the gap to prevent crack has been obtained.
A new semiconductor package based on the proposed strength evaluation method is working well without cracking.
Thus, the capability and validity of the proposed evaluation method has been proved.