A flexible thin film impedance sensor has been developed. Device manufacturing process and preparation of test wafers are described. Sensors with ring shaped Au electrodes have been fabricated on a polyimide substrate using Si wafer as a temporary substrate. The sensors have been characterized by means of Agilent 4294A analyzer and tested in measurements of impedance of human skin, Si wafers and other materials. Results of indirect measurements of samples covered with dielectric layer (SU-8, glass) confirm advantages of the sensors.
In this paper we describe the method for monitoring the progress of electrochemical deposition process. The procedure allows to control the deposition of metals as well as conductive polymers on metallic seed layer. The method is particularly useful to very thin layers (1-10 nm) of deposited medium which mechanical or optical methods are troublesome for. In this method deposit is grown on the target and on the test silicon micro-cantilever with a metal pad. Galvanic deposition on the cantilever causes the change of its mass and consequently the change of its resonance frequency. Changes of the frequency is measured with laser vibro-meter then the layer thicknesses can be estimated basing on the cantilever calibration curve. Applying this method for controlling of gold deposition on platinum seed layer, for improving the properties of the biochemical sensors, is described in this paper.
In this paper authors present design, technology and application of soft silicon dioxide AFM cantilevers. Novel technology allows for manufacturing ultra-soft cantilevers equipped with silicon tip. Mechanical properties of developed probes were tested and finally applied in AFM measurements of fragile samples.
In the paper, the testing method of DTMF circuits applied for dialing signal generation in telecommunication systems is described. The method enables determining: frequency, amplitude, and harmonic distortions of DTMF signals generated by tested integrated circuit. It was developed by the authors. Application of digital IIR filters and Fourier transform provides good accuracy and constant metrological parameters of the test system in connection with short test time. As a result of the developed method, the automatic telephone test system TAT- 92 controlled by a personal computer is designed. This paper describes the problem, the solution, and the comparison of new method and classical method, based on analog filters.