Particle Assembling on a Plate using Mechano‐Chemical Reaction

Particle assembling on a basal plate such as a silicon wafer or metal plate is an important technique for electronics, micro‐devices and the sensor industry. A new method of particle assembling using mechano‐chemical reaction is proposed. In this method, a plate surface is treated to hydrophilic condition as the first step, then a diamond needle scratches the plate (fixed on a computer controller X‐Y stage) in higher alcohol solution as the second step. During this time, the scratched surface is changed from a hydrophilic condition to hydrophobic by mechano‐chemical reaction. In the third step, particles with a hydrophobic surface are sprinlked on the plate, then it is washed with clean water. In this procedure, the hydrophobic particles are removed from the hydrophilic surface and only remain on the hydrophobic scratched surface by hydrophobic attraction. Using this new particle assembling method, we can arrange spherical silica particles in a linear scratch on silicon wafers or metal plates. The remarkable feature of this method is that expensive equipment such as electron or ion beam lithography is not necessary, and particle assemblies can be performed on a conductivity plate such as metal plate.