RF Measurements of Die and Packages by Scott A. Wartenberg Packages are becoming as small as die, and even printed circuit boards (PCBs) are being patterned for ground-signal-ground (GSG) coplanar waveguide (CPW) probes. Plastic packaged integrated circuits (ICs) are available up to 10 GHz, and even they depend on CPW transitions. CPW probing and modern ICs go hand in hand, and this book provides an excellent overview and reference to both. It is hard to find a modern IC above 10 GHz that is not designed for CPW probing. I can remember when Cascade Microtech launched the first probe station and how rapid a success it became. These days, the field has broadened, and competitors like Picoprobe can deliver custom probes in a matter of days, complete with calibration substrates and error coefficients. Dr. Wartenberg’s book, RF Measurements of Die and Packages, is a timely and useful book. While this book covers a lot of ground, it mainly focuses on CPW probing of die and packages. The book is clearly written, with excellent figures and generally a good set of references. In nine chapters the book takes a tour through radio frequency (RF) test systems, calibration, test fixturing, die measurements, package measurements, test systems, and future trends. Chapter 1 is an introduction that sets up the equipment and methods for RF testing. A great deal of RF measurement has to do with getting signal and bias to the device without deteriorating either, or at least knowing how to correct the deterioration. Appropriately, the second

Rf measurements of die and packages

Excimer-Lampen basierend auf Dielektrisch Behinderten Entladungen (DBD) sind effiziente Quellen ultravioletter Strahlung. Diese Arbeit verbindet theoretische Betrachtungen mit der praktischen Verifikation neu entwickelter Topologien und Betriebsmodi, um DBEs effizient mit kurzen Hochspannungspulsen zu betreiben. Durch transformatorlose Topologien und Nutzung von SiC Leistungshalbleitern konnten Effizienzen von bis zu 92 % und Pulsfrequenzen von bis zu 3.1 MHz erreicht werden. Dielectric barrier discharge (DBD) excimer lamps emit vacuum-UV optical radiation. This work presents novel methods for efficiently operating DBDs with short, high-voltage pulses. Transformer-less systems utilising SiC power semiconductor switches are presented. Pulse frequencies of up to 3.1 MHz and peak inverter efficiencies of 92 % were achieved. The work encloses both mathematical backgrounds of pulsed resonant circuits and practical implementation of low-inductive power stages. Umfang: 212 S. Preis: €54.00 | £50.00 | $95.00

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Resonant Behaviour of Pulse Generators for the Efficient Drive of Optical Radiation Sources Based on Dielectric Barrier Discharges

This paper demonstrates the integration of giant magnetoresistance (GMR) spin torque oscillators (STO) with dedicated high frequency CMOS circuits. The wire-bonding-based integration approach is employed in this work, since it allows easy implementation, measurement and replacement. A GMR STO is wire-bonded to the dedicated CMOS integrated circuit (IC) mounted on a PCB, forming a (GMR STO + CMOS IC) pair. The GMR STO has a lateral size of 70 nm and more than an octave of tunability in the microwave frequency range. The proposed CMOS IC provides the necessary bias-tee for the GMR STO, as well as electrostatic discharge (ESD) protection and wideband amplification targeting high frequency GMR STO-based applications. It is implemented in a 65 nm CMOS process, offers a measured gain of 12 dB, while consuming only 14.3 mW and taking a total silicon area of 0.329 mm2. The measurement results show that the (GMR STO + CMOS IC) pair has a wide tunability range from 8 GHz to 16.5 GHz and improves the output power of the GMR STO by about 10 dB. This GMR STO–CMOS integration eliminates wave reflections during the signal transmission and therefore exhibits good potential for developing high frequency GMR STO-based applications, which combine the features of CMOS and STO technologies.

Integration of GMR-based spin torque oscillators and CMOS circuitry

In this thesis, the results of intensive electrical characterization, modeling
and the design of hardware with thin film tunable capacitors, i.e., dielectric
varactors, has been presented and discussed. Especially the quality factor
Q and the tuning ratio of the tunable capacitors have been studied, since
these are crucial parameters for reconfigurable RF front-end applications
for mobile phones.
In Chapter 2, a literature survey was summarized describing the state of the
art Q and for different tunable capacitor technologies based on varactor
diodes, dielectric varactors, semiconductor-switched capacitors, and micromachined
electro mechanical systems. The Q() relations were described
separately by using basic physical models. However, the relations could be
described with a single Q() formula. The study concludes that RF microelectro-
mechanical switches have the highest tuning potential with a high
Q, but are relatively large in size. For continuous, moderate tuning ranges
highly doped GaAs varactor diodes could offer the best performance. Dielectric
varactors will be most attractive for small physical size and low cost
devices.
In Chapter 4, it was discussed how RF tunable capacitors based on thin film
barium strontium titanate (BST) were designed, fabricated, and measured.
In addition, a dedicated analysis technique was developed to separate the
electrical dissipation in the resistive electrodes from the dissipation in the
dielectric oxide films.
In Chapter 5 it was shown how voltage-dependent impedance measurement
errors, using a commercial wide-band bias-tee, could be prevented in RF C(Vdc) measurements by an additional open calibration or by employing a
custom-made wide-band bias-tee.
In Chapter 6, the Q and were studied as a function of barium to strontium
composition and doping in the BST films. A higher Q and a lower was
measured for a lower barium content in the BST films. Cation doping in the
BST films can have a similar effect. The electrical characterization results
were utilized as an input to further improve the capacitors RF performance.
In Chapter 7, a ferroelectric capacitor model has been implemented as a
new component in the design environment ADS. The model can describe a
C(Vdc) measurement by incorporating only 4 fit parameters.
In Chapter 8, a 2nd order bandpass transmit filter and a low-pass impedance
matching network was designed and simulated in ADS, to obtain the Q()
requirements for ferroelectric capacitors. A very high Q was required in the
filter for the inductor and capacitor components to fulfill the customer specifications.
Furthermore, an adaptive antenna impedance matching network
was designed and simulated for a user, which covers the antenna with his
hand resulting in a de-tuned antenna. Two cascaded low-pass L-sections
improved the antenna impedance matching. The simulation results, using
practical feasible values for the components, for the latter networks pointed
out that tunable ferroelectric capacitors are promising components.
Summarizing this thesis, the simulations and device characterization provided
the link between the applications and the performance requirements
of tunable capacitors. This could be the basis to optimize the ferroelectric
materials and devices for RF applications.

/pdf/thin-film-barium-strontium-titanate-capacitors-for-tunable-3poelm694w.pdf

Thin film barium strontium titanate capacitors for tunable RF front-end applications

Wide bandgap semiconductors as Silicon Carbide (SiC) lead to devices with smaller body capacitances and thereby support the continuous rise of operating frequency and switching speed of switch mode power supplies. However, parasitic elements coming from the real world setup gain more and more impact on system performance. In order to identify parasitic circuit components and corresponding resonances, this work is about small-signal impedance spectra measurements of power electronic circuits. Knowing the involved parasitics, destructive resonance phenomena can be avoided and electromagnetic radiation can be reduced. In order to include voltage drift effects of capacitive circuit elements, also impedance measurements with high voltage DC-bias were performed. For that, a broadband DC-blocker with 1 kV bias voltage rating was developed. Exemplary, two applications were investigated closer: a power semiconductor dynamic test circuit and an RF half-bridge inverter for the pulsed operation of dielectric barrier discharge (DBD) light sources. (6 pages)

https://www.lti.kit.edu/rd_download/licht2006/120330_PEMD2012_Meisser-pubwebpage.pdf

Impedance characterization of high frequency power electronic circuits

During the AC impedance characterization of devices, from the kHz-range up to the GHz-range, accuracy can be lost when a DC voltage is applied. Commercial high-voltage broadband bias-tees are often voltage-dependent, which can cause inaccuracies at low frequencies. A calibration technique with applied bias significantly improves the measurement accuracy. Additionally, a bias-tee has been developed with a voltage-independent capacitor, suitable for DC voltages up to 500 V showing excellent performance up to several gigahertz. PIN diode limiters protect the measurement equipment from damage in case of a device breakdown.

/pdf/reducing-ac-impedance-measurement-errors-caused-by-the-dc-1ay0rnmd6d.pdf

K. Reimann

Papers

Reducing AC impedance measurement errors caused by the DC voltage dependence of broadband high-voltage bias-tees