Combinatorial masked deposition: Simple method to control deposition flux and its spatial distribution

Deposition flux is an important factor that determines the structures of vapor-deposited materials. However, controlling this flux over a wide range is difficult using only a single apparatus. In this work, we developed a simple method, called combinatorial masked deposition (CMD), that enables a series of deposition fluxes and their respective distribution to be realized on a single sample by just setting a mask with holes of different sizes above a substrate. The degree of reduction in deposition flux can be controlled by the hole size and distance between the given point and the hole. The characteristics and applicability of CMD were evaluated by two experiments. In the first experiment, Cu nanoparticles were formed by sputter-deposition on a-SiO ₂ at different Cu deposition fluxes. The nanoparticles had a higher number density and smaller size when deposited at 0.80 nm/s for 2.5 s than when deposited at 0.014 nm/s for 140 s. In the second experiment, metal-induced crystallization of amorphous Si (a-Si) was done with spatially distributed Ni additives. The CMD method can realize a series of Ni flux distributions and was successfully used to form 100 different profiles of Ni concentration on a single sample, thus enabling efficient screening of concentration profiles to enhance grain size.