Dopant enhanced solar cell and method of manufacturing thereof

A method for manufacturing a solar cell based on a silicon substrate, comprising:

• providing the silicon substrate;
• creating on said surface a layer stack comprising:
• creating a thin oxide layer on a surface of the silicon substrate,
• and creating a doped polysilicon layer on the thin oxide layer, the doped polysilicon layer containing a dopant species of a first conductivity type,
• such that the layer stack comprises the thin oxide layer arranged as a tunnel oxide layer in-between said surface of the silicon substrate and the doped polysilicon layer;
• the method further comprising:
• creating in a surface of the silicon substrate a dopant profile of a dopant species of the first conductivity type,
• wherein the creation of the dopant profile in the silicon substrate is done either in a first process preceding the creation of the doped polysilicon layer or in a second process simultaneously during the creation of the doped polysilicon layer, and wherein the dopant profile in the silicon substrate is created under such conditions that the dopant profile of the dopant species of the first conductivity type in the silicon substrate has a maximal dopant level between about 1×10+18 and about 3×10+19 atoms/cm3 and at a depth of at least 200 nm within the silicon substrate has a dopant atom level of about 1×10+17 atoms/cm3,
• wherein the method comprises
• creating on the layer stack metal contacts that locally penetrate into at least the polysilicon layer, wherein the metal contacts are created from a pattern of fire-through metal paste on the layer stack by a fire-through annealing step, such that the metal contacts are fire-through metal contacts that locally fully penetrate the polysilicon as well as the thin oxide, resulting in local contacts between the metal and the silicon substrate, and the metal contacts are locally in direct contact with the silicon substrate.