摘要 |
A method and application for detecting and measuring the presence of a binding target material (64) employs a semiconductor device (50) having a receptor-covered surface (90) topgate (60), separated by a dielectric layer (58) from a substrate (56). Receptors (66) attached to this surface exhibit a chemical selectivity function. Binding occurs in a test solution (52), with charge associated with the target material (64) modulating at least one device characteristic. According to the present invention, measurement may occur under dry conditions, at a time and location different from when binding occurred, thus substantially eliminating problems associated with ionic shielding and reference electrodes, so prevalent with prior art wet measurement techniques. Preferably the device (50) includes backgate (62) to which a bias may be applied to restore the device's pre-binding characteristics. Measurement of the restorative backgate bias provides a signal indicating binding of the desired target material. |