Particle arrays with patterned pores by nanomachining with colloidal masks.

In summary, we have developed a new strategy for the fabrication of arrayed colloidal particles well-ordered nanometric holes of three or four fold symmetry by anisotropic reactive ion (plasma) etching of self-organized layers of colloidal spheres. We demonstrated that a mesoporous silica matrix with regular open windows could be used as a lithographic mask and the resulting arrangement of pores on a particle was dependent on the orientation of the colloidal particle stacking. A variety of organic and inorganic materials such as metals for metal-polymer composites, DNA and proteins, semiconducting and ceramic materials, and other polymers and small chemicals can be incorporated via chemical and physical attachment. Particles with patterned pores and composite particles by our nanomachining process can be used as novel functional materials in the field of electronics, photonics, and biotech areas.