Laser-Induced Backside Annealing Using Fluid Absorber

A method of applying a thin film to a substrate, comprising:

• employing a laser that provides a laser beam at a predetermined wavelength that is substantially transmissive through said substrate;
• selecting a coating material that is substantially transmissive at said predetermined wavelength and applying said coating material to said substrate to define a coated surface;
• associating a containment vessel with the coated surface to define a fluid containment chamber that includes within its interior at least a portion of the coated surface;
• selecting a fluid absorber material that is substantially absorptive at said predetermined wavelength and introducing said fluid absorber material into said containment chamber so that the fluid absorber material contacts said portion of the coated surface;
• transmitting said laser beam through the substrate and also through the coating material to strike the fluid absorber material in a region substantially adjacent an interface between the fluid absorber material and coating material and thereby supply optical energy to the fluid absorber material causing the fluid absorber material to gain heat in the region where struck by the beam;
• and
• allowing heat from said fluid absorber material to propagate to a localized region of coating material adjacent said interface in a quantity sufficient to anneal the coating material in the localized region.