Embedding of chips in flex and rigid substrates: Impact on thermal and mechanical performance

This paper summarises the thermal and mechanical characterisation embedded chips in flex and rigid substrates. Besides the technical integration issues, both technologies are also coping with thermal and mechanical issues. From thermal point of view, it is important to have a good thermal conductive path to conduct the heat towards the environment. From mechanical point of view, the thermo-mechanically induced stresses can become very high. In case of flex, also bending can add additional stresses. Therefore, simulation is very useful as a first virtual prototyping tool to analyse and finally optimise the structural design in order to have a low thermal resistance and sufficiently high reliability. The thermal simulation results are validated by experimental results.