Crystalline solar cells based on n-type silicon promise higher energy conversion efficiencies. In order to allow for cost effective production, the present dissertation introduces the concept of co-diffusion, which greatly simplifies production and reduces cost. The co-diffusion approach is based on a doped layer deposited by atmospheric pressure chemical vapor deposition and an atmosphere containing POCl3 and allows to fabricate co-diffused bifacial n-type solar cells (CoBiN) with peak efficiencies of 19.9 percent.