Patent ID: 7102363
Filing Date: 2006-09-05
Classification: G01R,H01L

Abstract:
1. A method for non-contact measurement of microwave capacitance of miniature structures of interest of integrated circuits under study, comprising the steps of: building at least one test key on a wafer of interest, said at least one test key including first pads and a test key portion coupled to said first pads, said test key portion replicating the miniature structure of interest of the integrated circuit, the dimensions of said test key portion falling in a predetermined range of dimensions corresponding to the dimensions of said miniature structure of interest; positioning a near-field microwave probe at a predetermined distance from said first pads of said at least one test key; measuring a resonant frequency F building at least one “short” calibration key on the wafer of interest, said “short” calibration key including second pads coupled each to the other by a conducting portion; positioning said near-field microwave probe said predetermined distance from said second pads of said at least one “short” calibration key; measuring a resonant frequency F building at least one “open” calibration key on the wafer of interest, said “open” calibration key including third pads isolated one from another; positioning said near-field microwave probe said predetermined distance from said third pads of said at least one “open” calibration key; measuring a resonant frequency F calculating the microwave capacitance C wherein F op is the resonant frequency of said near-field microwave probe for the “open” calibration key, F sh is the resonant frequency of said near field microwave probe for the “short” calibration key, F tot is the resonance frequency of said near-field microwave probe for the test key, Z 0 is the characteristic impedance of said near-field microwave probe, L is the resonator length, ε 0 is the absolute electric permittivity of a vacuum, μ 0 is the absolute permeability of a vacuum, and ε eff is the effective dielectric constant of the transmission line that forms said near-field microwave probe.