Patent ID: 8492160

Claim:
A method of processing one or more materials using a probe device, the method comprising: providing a substrate member baying a buttered fluid overlying the substrate member, the buffered fluid having one or more species mixed within the buffered fluid, the buffered fluid comprising a first pH range that makes the one or more species unreactive with each other and the substrate, the one or more species selected to be reactive to each other and the substrate or with only the substrate in a second pH range; suspending a probe device coupled to a tip region, the tip region having a determined spatial size; moving the probe device including the tip region toward a surface of the substrate member while maintaining the tip region immersed in the buffered fluid; applying an electrical bias on the probe device relative to a reference potential to cause the tip region to change in electrical characteristic so that the change in electrical characteristic is applied to a localized volume of the fluid of less than about 100 nm in diameter from the tip region of the probe device, creating a pH gradient within the localized volume, the pH gradient being within the second pH range, while the fluid outside the localized volume remains at about the first pH; and wherein a portion of the one or more species located within the localized volume reacts with each other and the substrate or with only the substrate to pattern the substrate and a portion of the one or more species located outside the localized volume does not react with each other and the substrate or with only the substrate.