**6. References**

Barybin A.A., Mikhailov A.I., Parametric interaction of space-charge waves in asymmetric thin-film n-GaAs structures, Tech. Phys.,vol. 48, no. 6, pp. 761 – 767, 2003.

	- Beck A.H.W, Space-charge waves and slow electromagnetic waves, Pergamon, New York, 1958.

**Chapter 11** 

© 2012 Hirano et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2012 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

**Accuracy Investigation of De-Embedding** 

**Simulation for On-Wafer RF Measurements** 

Takuichi Hirano, Kenichi Okada, Jiro Hirokawa and Makoto Ando

Millimeter-wave CMOS RF circuits have received substantial attention in recent years, motivated by advances in CMOS processing. Figure 1 shows on-wafer measurement using probes, which is commonly used in research and development of RF front-end circuits. Deembedding is necessary to remove the effect of pads in on-wafer measurements of RF circuits. Thru-Reflect-Line (TRL) calibration technique [1][2][3] and the de-embedding technique using open and short patterns [4] have been used conventionally. The authors applied the Thru-Line (TL) de-embedding technique [5] to remove the effect of pads from the measured S-parameters of RF circuits on a Si CMOS substrate. The TL de-embedding technique requires two patterns (Thru and Line) while the TRL de-embedding requires three patterns (Thru, Reflect and Line). The TL de-embedding technique can characterize left and right pads under the assumption that left and right pads have the same characteristics while TRL de-embedding cannot characterize pads, without knowing characteristic impedance of the line used for example. Other de-embedding methods, such as double delay [6], throughonly [7], and multi line (or L-2L) de-embedding [8][9], have been proposed. However, these all use approximation of pads, or parasitic component, by an equivalent circuit model while the TL de-embedding method treats pads rigorously with S-parameters. The effectiveness of

It is very difficult to keep repeatability of measurement in such high frequencies over millimeter-wave band. Hence, the electromagnetic (EM) simulation technology becomes important. This paper explains EM simulation modeling for on-wafer measurement using a GSG probe. By utilizing the result of EM simulation, the accuracy of de-embedding

and reproduction in any medium, provided the original work is properly cited.

Additional information is available at the end of the chapter

TL de-embedding has been investigated in [10].

techniques (open-short, TRL, and TL) are compared and discussed.

http://dx.doi.org/10.5772/48431

**1. Introduction** 

**Techniques Based on Electromagnetic** 


Takuichi Hirano, Kenichi Okada, Jiro Hirokawa and Makoto Ando

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/48431
