Enhancement Effect of Patterning Resolution Induced by an Aluminum Thermal Conduction Layer with AgInSbTe as a Laser Thermal Lithography Film

We employ an aluminum (Al) film as a thermal conduction layer under the laser thermal lithography AgInSbTe phase-change film to improve the patterning resolution in laser thermal lithography. The patterns were fabricated by laser writing and wet-etching. The laser writing was conducted by a setup where the laser wavelength and the numerical aperture of the converging lens were 405 nm and 0.90, respectively. The wet-etching was carried out in a 17wt% ammonium sulfide solution. Experimental results indicate that the patterning resolution enhancement induced by an Al thermal conduction layer is more than 20% compared with that of the samples without an Al thermal conduction layer. The analysis reveals that the resolution-enhancing effect may be due to the changes of heat diffusion directions induced by the Al thermal conduction layer.