The present disclosure teaches a method and apparatus to gel a dopant material, which may be a low viscosity liquid, and apply it towards beneficially coating dopant liquid in the manufacture of a three-dimensional thin-film solar cell substrate. As an alternate to using high viscosity dopants, a dopant coating liquid, which is typically distributed in low viscosity alcohol based liquid forms, may instead be utilized as a dopant material in a gelatinous state towards the manufacture of a three-dimensional thin-film solar cell substrate. The methods and devices disclosed herein provide for enhancing the high viscosity characteristics of a dopant material. The present disclosure teaches the use of the dopant material in its gelatinous state towards an exemplary cavity filling method. The more cotable dopant material is applied in an exemplary coating layout and an exemplary integrated coating system to achieve improvements in coating coverage with regards to uniformity, which may be, but is not limited to, homogeneity, color uniformity, opacity, and density of the dopant material.