Strain-balanced super-lattice (SL) has been proved as a really potential structure to tune the bandgap of one junction in a tandem solar cell to achieve the optimized design as well as to pursue high efficiency single junction solar cell. Comparing with normal multi-quantum well solar cell, it takes advantage of a minimized drop in open circuit voltage which is due to the unique and rapid carrier transport mechanism. Additionally, strain balance technique is very significant to implement such a complicated structure with minimum defects related loss. In this report, we focus on how to make a simple and smart design for the thin period structure growth. A strain compensation layer outside active (super-lattice) region has been proposed to allow efficient carrier tunneling through thin barrier layer while maintain the overall strain balance of entire solar cell.