Patent ID: 6998230

Claim:
A method A method of fabricating at least one addressable array of biopolymers with multiple features on a substrate using a drop deposition apparatus having a drop dispenser unit and a sensing element, comprising: (a) for each of multiple addresses, dispensing droplets carrying the biopolymers or biopolymer precursors from a drop dispenser unit onto the sensing element, and onto the substrate so as to fabricate the array; (b) detecting electrical signals resulting from dispensed droplets striking the sensing element; (c) evaluating a performance characteristic of the deposition apparatus based on the detected signals wherein the sensing element optionally comprises the substrate; additionally comprising: when after the dispensing of some droplets onto the substrate an error is detected in which an evaluated performance characteristic is outside a predetermined tolerance, then the source of the error is corrected prior to dispensing of other of the droplets onto that same substrate or the deposition apparatus is operated so as to compensate for the error during dispensing of other of the droplets onto that same substrate.