Photoabsorption in carbon and silicon layer of phosphorous doped camphoric carbon/p-silicon (n-CC/p-Si) solar cell

Photoresponse characteristics of heterostructure solar cells, fabricated by depositing a phosphorous (P) doped carbon (n-C) layer on a p-type silicon (Si) substrate (n-C/p-Si cell), have been studied. The camphoric carbon (CC) targets containing varying amounts of P ranging from 1% to 7% by mass were used in a pulsed laser deposition chamber for the deposition of the carbon layers of the cells under analysis. The quantum efficiency of these cells was measured in the ultraviolet-visible-infrared region (300-1200 nm), which is found to vary with the P content in the carbon layer. The individual contributions of the carbon and silicon regions to the overall photoresponse are extracted by deconvoluting the overall photoresponse spectra. The relative contribution of the carbon region is found to increase with the P content up to 5 wt.% P in the carbon layer of the cell and decreases thereafter. This trend is similar to that of the optoelectronic properties of the P-doped CC films.