In this letter, we present a compact, tunable delay line based on left-handed nonlinear transmission line (LH NLTL). The widely tunable range of the large group delay is achieved by controlling a reverse bias voltage of series varactors in the LH NLTL. The proposed tunable delay line can be made in a very compact form since its size is dominated by the cascaded varactors. Our experiment shows that the fabricated prototype exhibits tunable group delay between 1.2 ns and 2.2 ns at afrequency of 1.42 GHz with good return loss. The circuit size is merely 1.6 em in length.

In this paper, we present a compact, tunable delay line based on left-handed nonlinear transmission line (LH NLTL). The widely tunable range of the large group delay is achieved by controlling a reverse bias voltage of series varactors in the LH NLTL. The proposed tunable delay line can be made in a very compact form because its size is dominated by the cascaded varactors. Our experiment shows that the fabricated prototype exhibits tunable group delay between 1.2 and 2.2 ns at a frequency of 1.42 GHz and good return loss. The circuit size is merely 1.6 cm in length.

A very compact and frequency tunable Wilkinson power divider is suggested and demonstrated for the first time. By replacing k/ 4 section lines in a conventional Wilkinson power divider with varactor tunable, lumped-element synthetic transmission lines, dramatical size reduction and frequency tunability has been achieved. The prototype circuit fabricated shows excellent performance. For tunable frequencies from 0.71 to 0.99 GHz, the insertion loss is less than 3.52 dB, whereas the return loss and isolation are greater than 20 dB. Yet, the size of this voltage controllable Wilkinson power divider is only 4 mm by 8 mm, which occupies less than 3% area of original Wilkinson power divider structure.

Selection of optimized electron beam parameters for in-line monitoring is necessary to eliminate false signals. Application of electron beam to detect electrical defects, particularly leakages, for static random access memory (SRAM) cells poses a great challenge as it requires current measurement tool with nanometer resolution to complement it. By correlating the brightness intensity or the gray-level value to the measured current values, we have shown that conductive atomic force microscopy (C-AFM) can overcome this obstacle and can be used to verify the validity of the voltage contrast (VC) captured by HMI eScan3xx Ebeam inspection tool.

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