Boron-doped amorphous diamondlike carbon as a new p-type window material in amorphous silicon p-i-n solar cells

Chang Hyun Lee, Koeng Su Lim
1998 Applied Physics Letters  
A boron-doped hydrogenated amorphous diamondlike carbon (a-DLC:H͒ was prepared using a mercury-sensitized photochemical vapor deposition ͑photo-CVD͒ method. The source gases were B 2 H 6 and C 2 H 4 . By increasing the boron doping ratio (B 2 H 6 /C 2 H 4 ) from 0 to 12 000 ppm, the dark conductivity increased from ϳ10 Ϫ9 to ϳ10 Ϫ7 S/cm. A boron-doped a-DLC:H with an energy band gap of 3.8 eV and a dark conductivity of 1.3ϫ10 Ϫ8 S/cm was obtained at a doping ratio of 3600 ppm. By using this
more » ... . By using this film, amorphous silicon (a-Si͒ solar cells with a novel p-a-DLC:H/p-a-SiC double p-layer structure were fabricated using the photo-CVD method and the cell photovoltaic characteristics were investigated as a function of a-DLC:H layer thickness. The open circuit voltage increased from 0.766 V for the conventional cell with a 40-Å-thick p-a-SiC to 0.865 V for the cell with a p-a-DLC:H ͑15 Å͒/p-a-SiC ͑40 Å͒ double p-layer structure. The thin ͑Ͻ15 Å͒ p-a-DLC:H layer proved to be an excellent hole emitter as a wide band gap window layer.
doi:10.1063/1.120659 fatcat:a2holtmbvnesvhlvstulsmf3aa