High mobility monolithic p-i-n diodes

A method of forming a high-current density vertical p-i-n diode on a substrate in a substrate processing region in a substrate processing chamber, the method comprising:

• transferring the substrate into the substrate processing region;
• flowing a group-IV-element-containing precursor having a group-IV flow rate while also flowing hydrogen with a hydrogen flow rate into the substrate processing region to form a polycrystalline semiconducting film on the substrate;
• forming an RF plasma in the substrate processing region;
• doping the semiconducting film during formation to form a vertical p-i-n film stack by sequentially
• (1) supplying a first dopant-containing precursor at a first dopant flow rate during formation of a first doped layer,
• (2) supplying essentially no flow rate of dopant-containing precursor during formation of an intrinsic layer,
• (3) supplying a second dopant-containing precursor at a second dopant flow rate during formation of a second doped layer,
• wherein formation of the first doped layer, the intrinsic layer and the second doped layer occur without exposing the substrate to atmosphere between formation of adjacent layers whereby oxygen incorporation near the interface is reduced and electronic mobility is improved, and wherein one of the first doped layer and the second doped layer is an n-type layer and the other is a p-type layer;
• and
• removing the substrate from the substrate processing region.