Various stress relief structures are provided for effectively reducing thermal stress on a semiconductor chip in a chip package. Trenches on a metal substrate are created in groups in two-dimension, where each trench is opened from top or bottom surface of the metal substrate and in various shapes. The metal substrate is partitioned into many smaller substrates depending on the number of trench groups and partitions, and is attached to a semiconductor chip for stress relief. In an alternative embodiment, a plurality of cylindrical metal structures are used together with a metal substrate in a chip package for the purpose of heat removal and thermal stress relief on a semiconductor chip. In another alternative embodiment, a metal foam is used together with a semiconductor chip to create a chip package. In another alternative embodiment, a semiconductor chip is sandwiched between a heat sink and a circuit board by solder bumps directly with underfill on the circuit board.