scispace - formally typeset
Search or ask a question
Author

Gary A. Patrizi

Bio: Gary A. Patrizi is an academic researcher from Sandia National Laboratories. The author has contributed to research in topics: Photonics & CMOS. The author has an hindex of 9, co-authored 23 publications receiving 385 citations.

Papers
More filters
Journal ArticleDOI
TL;DR: In this paper, the performance of nanoelectromechanical (NEMS) switches is evaluated with one of the switches having a measured switching time of 400 ns and an operating voltage of 5 V.
Abstract: We designed, fabricated and measured the performance of nanoelectromechanical (NEMS) switches. Initial data are reported with one of the switch designs having a measured switching time of 400 ns and an operating voltage of 5 V. The switches operated laterally with unmeasurable leakage current in the 'off' state. Surface micromachining techniques were used to fabricate the switches. All processing was CMOS compatible. A single metal layer, defined by a single mask step, was used as the mechanical switch layer. The details of the modeling, fabrication and testing of the NEMS switches are reported.

82 citations

Journal ArticleDOI
TL;DR: In this paper, lifetime limitations and failure analysis of many packaged RF MEMS ohmic contacting switches with Au-Au, Au-Ir, and Au-Pt contact materials operating with 100 μN of contact force per contact in hermetically sealed glass wall packages.
Abstract: We present lifetime limitations and failure analysis of many packaged RF MEMS ohmic contacting switches with Au–Au, Au–Ir, and Au–Pt contact materials operating with 100 μN of contact force per contact in hermetically sealed glass wall packages. All metals were tested using the same switch design in a controlled environment to provide a comparison between the performance of the different materials and their corresponding failure mechanisms. The switch lifetimes of the different contact materials varied from several hundred cycles to 200 million cycles with different mechanisms causing failures for different contact materials. Switches with Au–Au contacts failed due to adhesion when thoroughly cleaned while switches with dissimilar metal contacts (Au–Ir and Au–Pt) operated without adhesion failures but failed due to carbon accumulation on the contacts even in a clean, packaged environment as a result of the catalytic behavior of the contact materials. Switch lifetimes correlated inversely with catalytic behavior of the contact metals. The data suggests the path to increase switch lifetime is to use favorable catalytic materials as contacts, design switches with higher contact forces to break through any residual contamination, and use cleaner, probably smaller, packages. (Some figures may appear in colour only in the online journal)

72 citations

Journal ArticleDOI
TL;DR: In this paper, the authors measured the contact resistance of radio frequency microelectromechanical system switches operating in an ultrahigh vacuum system equipped with in situ oxygen plasma cleaning capabilities, and the time dependence of the resistance was fit to power law extrapolations to infer contact creep properties and resistance values at t = ∞.
Abstract: Contact resistance measurements are reported for radio frequency microelectromechanical system switches operating in an ultrahigh vacuum system equipped with in situ oxygen plasma cleaning capabilities. Ru-based contacts were prepared by means of standard sputtering techniques, sputtering followed by postdeposition oxidation, (surface RuO2) or reactive sputtering in the presence of oxygen (bulk RuO2). In situ oxygen plasma cleaning lowered the resistance of Ru contacts by two or more orders of magnitude but not lower than Au contacts, irrespective of whether the Au contacts were cleaned. The time dependence of the resistance was fit to power law extrapolations to infer contact creep properties and resistance values at t=∞. Time-dependent creep properties of mixed Au-Ru contacts were observed to be similar to those of Au-Au contacts, while the absolute value of the resistance of such contacts was more comparable to Ru-Ru contacts. Prior to, and for short oxygen plasma exposure times, bulk RuO2 resistance v...

49 citations

Journal ArticleDOI
TL;DR: In this article, the authors presented improvements in RF microelectromechanical switch design and fabrication that demonstrated improved lifetimes in cycled switches, including the use of RuO2-Au contact metallurgy.
Abstract: We present improvements in RF microelectromechanical switch design and fabrication that demonstrated improved lifetimes in cycled switches. First, implementation of RuO2-Au contact metallurgy into an existing design showed improved switch lifetime over switches with Pt-Au, Ir-Au, and Au-Au contacts. Second, the switch design was changed to reduce impact upon switch closure, and the fabrication process was changed to avoid the use of polymer sacrificial materials while including the RuO2-Au contact metallurgy. Switches with the new design were cycled to 10 billion cycles with a resistance less than 4 Ω, an insertion loss of 0.4 dB, and an isolation of 28.0 dB at 10 GHz. We propose that the catalytic behavior of the RuO2 film prevents or delays the failure of the switches due to accumulation of carbon at the contacts. Additionally, the reduced impact upon closure prevented significant contact evolution during cycling.

43 citations

Journal ArticleDOI
TL;DR: In this paper, thin-film deposition techniques and resistor processing techniques to fabricate fine-line geometry resistors for InP-based electronics are reported, and the dependence of electrical properties, including resistivity, Seebeck ratio and temperature coefficient of resistivities, are reported for a wide range of nitrogen flow.

29 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: A review of the basic experimental structures of VCSELs is given in this paper, with emphasis on recent developments in distributed Bragg reflectors, gain media, as well as current and optical confinement techniques.
Abstract: This paper discusses the issues involving the design and fabrication of vertical-cavity surface-emitting lasers (VCSELs). A review of the basic experimental structures is given, with emphasis on recent developments in distributed Bragg reflectors, gain media, as well as current and optical confinement techniques. The paper describes present VCSEL performance, in particular, those involving selective oxidation and visible wavelength operation.

213 citations

Journal ArticleDOI
TL;DR: In this article, an overview of recent advances that have been achieved in understanding the basic physics of friction and energy dissipation in molecularly thin adsorbed films and the associated impact on friction at microscopic and macroscopic length scales.
Abstract: This review provides an overview of recent advances that have been achieved in understanding the basic physics of friction and energy dissipation in molecularly thin adsorbed films and the associated impact on friction at microscopic and macroscopic length scales. Topics covered include a historical overview of the fundamental understanding of macroscopic friction, theoretical treatments of phononic and electronic energy dissipation mechanisms in thin films, and current experimental methods capable of probing such phenomena. Measurements performed on adsorbates sliding in unconfined geometries with the quartz crystal microbalance technique receive particular attention. The final sections review the experimental literature of how measurements of sliding friction in thin films reveal energy dissipation mechanisms and how the results can be linked to film-spreading behavior, lubrication, film phase transitions, superconductivity-dependent friction, and microelectromechanical systems applications. Materials s...

190 citations

Journal ArticleDOI
TL;DR: In this paper, the state-of-the-art of the development of aluminum nitride (AlN) thin-film microelectromechanical systems (MEMS) with particular emphasis on acoustic devices for radio frequency (RF) signal processing.
Abstract: This article reports on the state-of-the-art of the development of aluminum nitride (AlN) thin-film microelectromechanical systems (MEMS) with particular emphasis on acoustic devices for radio frequency (RF) signal processing. Examples of resonant devices are reviewed to highlight the capabilities of AlN as an integrated circuit compatible material for the implementation of RF filters and oscillators. The commercial success of thin-film bulk acoustic resonators is presented to show how AlN has de facto become an industrial standard for the synthesis of high performance duplexers. The article also reports on the development of a new class of AlN acoustic resonators that are directly integrated with circuits and enable a new generation of reconfigurable narrowband filters and oscillators. Research efforts related to the deposition of doped AlN films and the scaling of sputtered AlN films into the nano realm are also provided as examples of possible future material developments that could expand the range of applicability of AlN MEMS.

172 citations

Journal ArticleDOI
TL;DR: In this paper, the authors provide a survey of conventional and unconventional lithography techniques used to fabricate complex micro-and nano-structured surfaces, including printing, molding, and embossing.

149 citations

Journal ArticleDOI
TL;DR: In this article, the authors evaluate tantalum nitride thin films fabricated using reactive sputtering with adjusted deposition parameters and determine the value of temperature coefficient of resistance (TCR) determined for the Ta2N resistor was - 103 ppm/°C.

148 citations