Abstract
Organic solar cells have been research in recent years. In order to raise short circuit current (Jsc) and Power consumption efficiency (PCE), One of the improve method is to add the active layer thickness. That will result in more photons absorption and product more excitons. Then the exciton diffusion length and lifetime have become important. These are major discussions in the thesis. It is famous to dope metal complexes in conjugate polymer. Heavy metal effect cause excitons have spin-orbit coupling. Singlet excitons can be cross to the triplet state by intersystem crossing. Excitons lifetime will increase obviously. After we doped PtOEP in conjugate polymer and device, it find the decreasing exciton lifetime. In bilayer devices, it can find the exciton diffusion length increase. The bilayer devices fabrication was post anneal 30mins and in 180 degrees. The photocurrent and PCE also increase in evidence. Otherwise, we try other materials, like Ir(mppy)3 and Natural Ru(II) which was compound in Chi Yun laboratory of National Tsing Hua University, to compare with PtOEP .