Fully scalable, analytical HF noise parameter equations for bipolar transistors are presented and experimentally tested on high-speed Si and SiGe technologies. A technique for extracting the complete set of transistor noise parameters from Y parameter measurements only is developed and verified. Finally, the noise equations are coupled with scalable variants of the HICUM and SPICE-Gummel-Poon models and are employed in the design of tuned low noise amplifiers (LNA's) in the 1.9-, 2.4-,and 5.8-GHz bands.

/pdf/a-scalable-high-frequency-noise-model-for-bipolar-1p8alxdsqv.pdf

A scalable high-frequency noise model for bipolar transistors with application to optimal transistor sizing for low-noise amplifier design

Fully scalable, analytical HF noise parameter equations for bipolar transistors are presented and experimentally tested on high speed Si and SiGe technologies. A technique for extracting the complete set of transistor noise parameters from Y parameter measurements only is developed and verified. Finally, the usefulness of the noise model is demonstrated in the design of tuned LNAs in the 1.9 GHz, 2.4 GHz, and 5.8 GHz bands.

/pdf/a-scalable-high-frequency-noise-model-for-bipolar-xx6a863box.pdf

A scalable high frequency noise model for bipolar transistors with application to optimal transistor sizing for low-noise amplifier design

A parameter-extraction approach for the heterojunction bipolar transistor (HBT), which combines the analytical approach and empirical optimization procedure, is developed. The extraction techniques for extrinsic base-collector capacitance and pad parasitics are also included in this approach. The cutoff operation of the HBT's is utilized to extract the values of the pad capacitances. An excellent fit between measured and simulated S-parameters in the frequency range of 50 MHz-36 GHz is obtained over a wide range of bias points.

A semianalytical parameter-extraction procedure for HBT equivalent circuit

Direct extraction is the most accurate method for the determination of equivalent-circuits of heterojunction bipolar transistors (HBTs). The method is based on first determining the parasitic elements and then the intrinsic elements analytically. The accuracy and robustness of the whole algorithm therefore is determined by the quality of the extraction of the extrinsic elements. This paper focuses on a new extraction method for the extrinsic capacitances which have proven to be the main source of uncertainty compared to the other extrinsic parameters. Concerning the intrinsic parameters, all the elements are extracted using exact closed-form equations, including exact expressions for the base-collector capacitances, which model the distributed nature of the base. The expressions for the base-collector capacitances are valid for both the hybrid-/spl pi/ and the physics-based T-topology equivalent circuits. Extraction results for InP HBT devices on measured S-parameters up to 100 GHz demonstrate good modeling accuracy.

A peeling algorithm for extraction of the HBT small-signal equivalent circuit

An improved HBT small-signal parameter extraction procedure is presented in which all the equivalent circuit elements are extracted analytically without reference to numerical optimization. Approximations required for simplified formulae used in the extraction routine are revised, and it is shown that the present method has a wide range of applicability, which makes it appropriate for GaAs and InP-based single and double HBTs. Additionally, a new method is developed to extract the total delay time of HBTs at low frequencies, without the need to measure h/sub 21/ at very high frequencies and/or extrapolate it with -20 dB/dec roll-off. The existing methods of finding the forward transit time are also modified to improve the accuracy of this parameter and its components. The present technique of parameter extraction and delay time analysis is applied to an InGaP/GaAs DHBT and it is shown that: (1) variations of all the extracted parameters are physically justifiable; (2) the agreement between the measured and simulated S- and Z-parameters in the entire range of frequency is excellent; and (3) an optimization step following the analytical extraction procedure is not necessary. Therefore, we believe that the present technique can be used as a standard extraction routine applicable to various types of HBTs.

/pdf/stepping-toward-standard-methods-of-small-signal-parameter-3nnebepk2y.pdf

Stepping toward standard methods of small-signal parameter extraction for HBTs

An extraction technique for determining the small-signal equivalent circuit model of an InP/GaInAs heterojunction bipolar transistor is presented. The equivalent circuit includes the extrinsic base collector capacitance and extrinsic base resistance. It is clearly indicated which elements are uniquely determined, and which elements are estimated. >

S.J. Spiegel

Papers

Extraction of the InP/GaInAs heterojunction bipolar transistor small-signal equivalent circuit