Development and irradiation performance of stencil masks for heavy-ion patterned implantation

Heavy-ion implantation is a powerful tool to conduct atomic injection and to create buried nanoparticles with good depth-controllability in dielectric material. Metal nanoparticle composites, especially, the metal ion implanted insulators (e.g. SiO2) with patterned nanoparticles are promising for plasmonic applications, possessing an enhanced surface plasmon resonance and nonlinear optical property as compared with randomly implanted specimens [1]. Contact masked implantation is one practical method for patterned implantation, which has advantage of reliable 2D nanoparticle spatial controllability without any abreactions. In this experiment, the Si stencil mask was made from top Si layer of SOI wafer by using e-beam lithography and plasma deep etching. The mask can be fabricated with required aspect ratio (from 3 up to 100), fine pore shape, surface flatness, and mechanical hardness. 60 keV Cu ion irradiation damage test shows that, below the fluence of 1 × 1017 ions/cm2, Si stencil mask can keep dimensional stability.

Research Highlights
► Patterned metal ion implanted insulators are promising for plasmonic applications.
► Contact masked implantation has advantage of reliable 2D nanoparticle spatial controllability without any abreactions.
► We developed the Si stencil mask from top Si layer of SOI wafer by using e-beam lithography and plasma deep etching.
► The Si stencil mask can keep dimensional stability after heavy ion irradiation with fluence of 1× 1017 ions/cm2.