Role of residual stress on crack penetration and deflection at a bimaterial interface in a 4-point bend test
The four-point bend (4PB) test has emerged as a method of choice in the semiconductor industry for obtaining bimaterial interface adhesion data. When measuring the interface adhesion using 4PB test, it is essential to obtain a crack through the interface of interest. In our previous work the effect of finite flaw size, boundary conditions and film thickness on the crack deflection or penetration at a bimaterial interface was studied, and it was determined that prior work on semi-infinite media cannot be directly used in the case of 4PB test. In this paper, we briefly discuss the origins and development of residual stress, and will expand our previous work to include the role these residual stresses play on the competition between deflection and penetration energy release rates of a bimaterial interface and the extent of which the previous assumption of two semi-infinite media can be accepted.
residual stress interface adhesion low k films crack propagation thin films mode mixity ic devices