Planar type micromachined probe with low uncertainty at low frequencies

In this paper, we proposed a planar type micromachined probe with low uncertainty and showed its feasibility in practical biomedical applications through the in vivo measurements of cancerous tissue xenografted on nude mice. We have succeeded in increasing the fringe capacitance at low frequencies by locating an aperture on the top side of probe. Furthermore, we showed experimental proof of low uncertainty at low frequencies through measurements of known liquid samples below 1 GHz. Measured results using the proposed probe showed superior agreement with the reference values of the Cole-Cole equation in comparison to measurements made using an open-ended coaxial probe. Muscle and tumor tissue samples of mice, as well as 0.9% saline as a liquid sample, were measured using the proposed probe from 1 GHz to 20 GHz, thus demonstrating the feasibility of this method as a practical biomedical application.