Julio Costa

Extracting small-signal model parameters of silicon MOSFET transistors

A novel approach to the extraction of small signal model parameters for silicon MOSFETs is described. This technique was developed to extract a high frequency model based only on S-parameter measurements to obtain both the intrinsic and parasitic resistance model parameter values of a small signal model.<<ETX>>

Silicon MOSFETs, the microwave device technology for the 1990s

Silicon MOSFET technology using 1.5- mu m gate lengths has demonstrated excellent performance for 900-MHz applications. Circuit results for low-noise amplifiers, power amplifiers, mixers, and oscillators using this technology are discussed in comparison to other device technologies. Device results for 0.6- mu m-gate-length devices showing the microwave performance of silicon MOS transistors are discussed. These results, together with scaling predictions, indicate that microwave silicon MOSFETs will play a major role in the 1990s. The performance of devices with 0.6- mu m gate lengths indicates that silicon MOS will be the FET technology of choice for applications below 3 GHz. Advantages such as high voltage characteristics, low thermal conductivity of silicon, and the high operating junction temperature make silicon MOS a technology with immense potential for high-voltage X-band power applications.<<ETX>>

Bonding pad models for silicon VLSI technologies and their effects on the noise figure of RF NPNs

VLSI technologies such as BiCMOS and high speed ECL Bipolar are candidates for mixed mode applications which include RF receiver functions. In order for these silicon technologies to achieve low noise characteristics one needs to optimize both the active device and the signal path to the IC interface. Studies in the bonding pad parasitics indicate that these path losses can be Very significant. This paper models the bonding pads and presents measured vs. modeled noise figure data for several bonding pad configurations.<<ETX>>

Silicon MOSFET technology for RF ICs

Application of silicon MOSFET technologies to high frequency RF transceiver functions will be presented. Starting with a description of the high frequency characteristics of silicon MOSFETs designed specifically for RF applications. These applications include several RF functions where silicon MOSFETs have not traditionally been used such as low noise amplifiers, balanced mixers, RF switches and integrated power amplifiers. Finally a description of the performance trade-offs associated with silicon BJT (Bipolar Junction Transistor) technology are given along with an evaluation of how BiCMOS (Bipolar-CMOS) technologies can sometimes serve as the best solution to RF IC designs. Another silicon MOSFET device well suited to RF applications is the Thin Film Silicon on Insulator (TFSOI) device [2] shown in Figure 2. This transistor is constructed in the same manner as the device in Figure 1 except that a layer of insulating dielectric is now present between the epi and the substrate. The buried oxide insulator dramatically reduces the source-substrate and drain-substrate capacitance that is inherent to classic MOSFET device architecture and i prohibits the use of a low impedance source ground contacts. 1 I \

Extracting 1/f noise coefficients for BJT's

We present a method for extracting the BJT SPICE noise model parameters AF and KF based on a general analysis of the small-signal equivalent circuit and the role of the internal BJT noise sources. The analysis is valid even for transistors with poor current gain and large base-collector conductance, for which the output noise characteristics may not be dominated by base flicker and shot noise. The method consists of interpreting the measured 1/f corner frequency versus DC current data in terms of the BJTs internal noisy small signal equivalent circuit. Measured data is presented for an implanted-emitter and two polysilicon-emitter bipolar technologies. >

Fast, accurate, on-wafer extraction of parasitic resistances and inductances in GaAs MESFETs and HEMTs

A novel method of extracting the parasitic resistance and inductance values for MESFETs, and high electron mobility transistors (HEMTs) is presented. The technique requires the use of only RF two-port measurement data, is extremely accurate, straightforward to implement and works equally well for both MESFETs and HEMTs. The technique makes use of cold-chip measurements in conjunction with a unique analysis that has proved to be both fast and robust. The method does not require that channel resistance or diode resistance be evaluated or that excessive values of gate current be used in the measurements.<<ETX>>

A silicon MOS process for integrated RF power amplifiers

A silicon-based technology is presented which integrates passive components with a silicon power MOSFET for use in integrated power amplifiers at UHF, VHF, and RF frequencies. This low-cost process incorporates capacitors, inductors, resistors, ground vias, transmission lines, and an ESD protection diode. A design library containing models and layouts for the active and passive components was compiled.

Modeling a new generation of RF devices: MOSFETs for L-band applications

Results on large-signal modeling efforts for a novel MOSFET technology for L-band RF applications are presented. A parameter extraction procedure which yields accurate RF MOS large-signal models using DC and S-parameter data is presented along with a comparison of measured and modeled class-B amplifier, mixer, and S-parameter data.<<ETX>>

RF silicon MOS integrated power amplifier for analog cellular applications

We report the RF performance of the first integrated power amplifier using silicon MOS field effect transistors, shunt and series capacitors, transmission lines, spiral inductors, ground vias and ESD protection devices. The amplifier provided an output power of 1.5 W and 56% efficiency at a supply voltage of 5.8 V (850 MHz) with 25 dB of small signal gain and more than 10 dB input return loss.

Modeling and measurement of 1/f noise characteristics of silicon BJTs

We present a method for measuring and extracting the BJT SPICE noise model parameters AF and KF based on an analysis of the general small signal equivalent circuit and the role of the BJT noise sources. Modeled and measured low-frequency noise data is presented for three high-frequency Motorola bipolar technologies.<<ETX>>