The concept of an organic p-i-n junction in which i-layer is a vacuum co-deposited layer of two different organic semiconductors was proposed and demonstrated, Co-deposited layers have a vast number of hetero-molecular (donor-acceptor) contacts acting as efficient photocarrier generation sites. A crystalline-amorphous nano-composite with spatially separated pathways for electrons and holes, which was formed by controlling the substrate temperature during co-evaporation, was revelaed to be suitable for co-deposited i-layer. p-i-n junction organic solar cells incorporating codeposited interlayer between fullerene and metal-free phthalocyanine showed the photo-electric conversion efficiency of 2.5% under the illumination of simulated solar light.