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`Historical Introduction to Capacitor
`Technology
`
`Key words: capacitor, capacitor history, ceramic capacitor, film capacitor, double layer capacitor,
`electrochemical capacitor
`
`Introduction to the Series
`Over the next several years, this magazine will publish a se-
`ries of papers, hopefully one per issue, on the subject of capaci-
`tor technology. The intention is to cover all important areas of
`the technology in some detail, including film, ceramic, electro-
`lytic, and double-layer capacitors. One of the authors (S. B.) will
`edit the series.
`
`Early History
`Invention of the Capacitor
`Capacitors are a good example of the fact that even the sim-
`plest device, in this case nothing more than an insulator between
`2 conductors, can become complex given 250 years of technical
`evolution. The beginning of capacitor technology is generally
`attributed to the invention in October 1745 of the Leyden jar by
`the German Ewald Georg von Kleist. Independently, Pieter van
`Musschenbroek, a Dutch physicist at the University of Leyden,
`discovered the Leyden jar in 1746 [1]. As originally constructed,
`the Leyden jar consisted of a narrow-neck jar partially filled with
`water with an electrical lead brought through a cork in the neck of
`the bottle to the water. In von Kleist’s implementation, his hands
`holding the jar formed the outer electrode. After charging the jar
`with an electrostatic generator connected to the water, von Kleist
`was able to give himself a painful shock by touching the lead to
`the water while still holding the jar, something he apparently
`did only once! The Dutch Leyden jar employed a foil electrode
`over the outside surface of the jar to form a true capacitor. The
`American journalist, statesmen, and inventor Benjamin Franklin
`showed that the water in the jar was not an essential element as
`had been thought by the inventors; as a result, he was able to
`make flat capacitors consisting of a sheet of glass between foil
`electrodes [2]. Faraday made major contributions to capacitor
`technology, including the concept of dielectric constant as well
`as the invention of the first practical fixed and variable capaci-
`tors. His contributions to capacitor technology are recognized in
`the unit for capacitance.
`
`Early Sources of Commercial Demand
`Capacitor technology did not evolve rapidly until the inven-
`
`Janet Ho and T. Richard Jow
`Army Research Laboratory, Adelphi, MD
`
`Steven Boggs
`Institute of Materials Science, University of
`Connecticut
`
`Capacitors are a good example of the
`fact that even the simplest device can
`become complicated given 250 years
`of evolution.
`
`tion of the vacuum tube (De Forest, 1907; Langmuir, 1916),
`which facilitated electronic amplifiers required for long-distance
`telephone (coast-to-coast, 1915) and practical radio technology
`first licensed commercially in 1920; however, the first AC line-
`powered radio was not introduced until 1927 (RCA Radiola 17).
`The rapid evolution of line-operated radio receivers created a
`large consumer product market for capacitors.
`
`Early Capacitors
`A wax-impregnated paper dielectric capacitor with foil elec-
`trodes was invented by Fitzgerald in 1876 [3]. The earliest capac-
`itors used in radio receivers employed foil and wax-impregnated
`paper (Figure 1) for power supply filtering and mica dielectric
`capacitors for RF circuits (Figure 2). As wax-impregnated paper
`and foil capacitors are quite bulky, the power supplies of these
`radios normally employed filter chokes, i.e., inductors, in com-
`bination with the rectifier and capacitors to reduce power supply
`ripple. For example, the first line-powered RCA radio employed
`two 1-µF capacitors and three filter chokes. Higher voltage ca-
`pacitors of the time were based on oil-impregnated paper and
`metal foil.
`
`20
`
`0883-7554/07/$25/©2010IEEE
`
`IEEE Electrical Insulation Magazine
`
`Petitioner Intel Corp., Ex. 1041
`IPR2023-00783
`
`

`

`Figure 1. Examples of early waxed paper and foil capacitors
`taken from antique radios. Such capacitors tend to be unreliable
`and are usually replaced with metalized polymer film capacitors
`when restoring a radio. Photo courtesy of P. I. Nelson, www.
`antiqueradio.org, and used with permission.
`
`Mica dielectric capacitors (Figure 2) were invented in 1909
`by William Dubilier, with principal application in the area of
`radio transmission. In 1915, Dubilier founded the Dubilier
`Condenser Company in New York, and in 1933, the company
`merged with Cornell Radio to form Cornell-Dubilier Electric.
`From the beginning, mica capacitors, typically silver mica, have
`been highly reliable because mica is an excellent dielectric with
`outstanding discharge resistance.
`Patents on the electrolytic capacitor (Figure 3) technology
`date back to 1897 when Charles Pollak was granted a patent
`for a borax electrolyte aluminum (Al) electrolytic capacitor,
`and the first wet electrolytic capacitors appeared in radios in the
`late 1920s. These had a very limited lifespan, and the company
`that introduced them went bankrupt. In 1936, Cornell-Dubilier
`opened a factory in Plainfield, NJ, and introduced a line of com-
`mer cial Al electrolytic capacitors. This might have been the first
`commercial production of electrolytic capacitors since failure
`of the technology in the late 1920s. Electrolytic capacitors did
`not become highly reliable until World War II when sufficient
`resources were devoted to identify and eliminate the causes of
`early failure [4].
`Ceramics have been used as electrical insulation since the
`earliest studies of electricity. As noted earlier, the first capaci-
`tor, the Leyden jar, was a ceramic capacitor. Prior to World War
`II, mica was the most common ceramic dielectric for capaci-
`tors, although porcelain, steatite, cordierite, and rutile were also
`used. Capacitors based on titanium dioxide (rutile) were avail-
`able commercially around 1926. The 1941 discovery of barium
`titanate [5] with a dielectric constant in the range of 1,000,
`about 10 times greater than any dielectrics known at the time,
`focused attention on the barium titanate family of materials for
`a range of wartime applications, including capacitors (Figure
`4). In the following decades, a great deal of effort was devoted
`
`Figure 2. Selection of early mica capacitors. From the begin-
`ning, mica capacitors were very reliable, as they are today. Their
`expense precludes widespread use today, although they are still
`available. Photo courtesy of William Harris, nbcblue@hotmail.
`com.
`
`to understanding the crystallography, phase transitions, and the
`optimization of this family of materials [6]. The development
`of multilayer ceramic capacitor (MLCC) fabrication using the
`tape casting and ceramic-electrode cofiring processes during
`the 1970s and 1980s expanded the range of ceramic capacitor
`application to larger capacitances and higher voltages depend-
`ing on whether the layers were arranged in series or parallel.
`At present, more than 1012 barium titanate–based MLCC are
`manufactured each year. Ceramic capacitors are not limited to
`barium titanate MLCC. A wide range of ceramic formulations
`has been developed, some with very high dielectric constants but
`usually with large temperature/voltage coefficients, and others
`with lower dielectric constants but lower, and in some cases near
`zero, temperature/voltage coefficients.
`A metalized, self-clearing paper capacitor was patented by
`Mansbridge in 1900 [5], [6] and was based on metalizing with
`a metal particle-filled binder, which resulted in fre quent shorts
`through the paper. Metalized paper capacitors reached maturity
`dur ing World War II, with Bosch manufacturing metalized paper
`capacitors using lacquer-coated paper and vacuum-deposited
`metal [7]. The lacquer reduced electrolytic corrosion of the metal
`and increased insulation resistance. Further attention was given
`to metalized paper capacitors around 1950 when they were in-
`
`January/February — Vol. 26, No. 1
`
`21
`
`Petitioner Intel Corp., Ex. 1041
`IPR2023-00783
`
`

`

`1950s and was produced as 12-µm metalized capacitor film by
`1954 [8]. Semi crys talline polypro pylene was discovered around
`1951 by multiple investigators, which resulted in patent litiga-
`tion that continued into the late 1980s! A 1959 paper [9] dis-
`cusses “Development of Plastic Dielectric Capacitors” made
`from polyethylene, polystyrene, polytetrafluoroethylene, PET,
`and polycarbonate, i.e., the most common capacitor films other
`than polypropylene. By 1970, film-foil capacitors (without pa-
`per) were being manufactured for electric utility applications.
`Capacitors based on electric double-layer charge storage
`were first patented by General Electric in 1957 but were never
`commercialized. Subsequent double-layer capacitor designs
`patented by Standard Oil of Ohio did lead to commercial prod-
`uct introduction in 1978 by Nippon Electric Corporation. Their
`Supercapacitor trademarked product was rated at 5.5 V and had
`capacitance values up to 1 F. These 5-cm3-size or smaller capaci-
`tors were used as battery substitutes to provide backup power
`for volatile CMOS computer memory. Products available today
`from about 2 dozen manufacturers around the world range in
`sizes up to 9 kF (9,000 F) at 2.7 V, with this largest-size device
`being easily held in one hand.
`Figure 5 presents a time line for the development of capacitor
`technology along with a corresponding cultural (musical) time
`line that may help relate technological and cultural/historical de-
`velopment.
`
`Present Challenges and Limitations
`At present, the important capacitor technologies are impreg-
`nated foil-polymer film (for high voltage, high current), met-
`alized film, ceramic, electrolytic, and electric double layer, al-
`though metalized paper is still used occasionally in “soggy foil”
`designs, i.e., self-clearing, fluid-impregnated, high-voltage ca-
`pacitors. Each of these major technolo gies faces challenges as
`they compete with each other for market share.
`Ceramic capacitor dielectrics exhibit high dielectric constant
`but low breakdown field. As a result ceramic capacitors provide
`very high capacitance but typically exhibit a low breakdown
`field as a result of porosity in the ceramic structure, which arises
`from incomplete consolidation of the ceramic particles during
`the manufacturing process. In addition, a higher dielectric con-
`stant material tends to have a lower breakdown field than a lower
`dielectric constant material simply because, at a given electric
`field, it stores more energy, which can precipitate breakdown.
`Thus, a major challenge in ceramic capacitor technology is to
`improve density and break down strength through techniques
`such as the use of nanoceramic powders, various forms of im-
`pregnation to reduce porosity, etc. The relatively low breakdown
`strength combined with very high dielectric constant of ceramic
`capacitors makes them well suited to low-voltage applications
`because the thickness can be matched well to the voltage. They
`are less well suited to high-voltage applications as a result of the
`low breakdown strength, although doorknob ceramic capacitors
`are manufactured to at least 50 kV, which is achieved by incor-
`porating a large safety margin at the expense of a low capaci-
`tance on the order of 1 nF.
`The failure mode of ceramic capacitors also presents a chal-
`lenge. Unlike polymer capacitors, which fail gracefully by oxi-
`
`Figure 3. Examples of early electrolytic capacitors taken from
`antique radios. These capacitors are also unreliable and are
`replaced when restoring such a radio. Photo courtesy of P. I.
`Nelson, www.antiqueradio.org, and used with permission.
`
`troduced into the tele phone system. Metalized paper capacitors
`were very reliable as long as they were dried care fully and sealed
`into a dry environment. Around 1954, Bell Labs took this system
`a step further by separating the lacquer from the paper and mak-
`ing capacitors based on 2.5-µm-thick metalized lacquer film that
`were substantially smaller than metalized paper capacitors [8].
`This could be the first metalized polymer film capacitor.
`Polyethylene terephthalate (PET) was patented by Whinfield
`and Dickson in 1941. A very strong PET, trademarked Mylar
`by Dupont (1952), evolved from work on Dacron in the early
`
`Figure 4. Examples of early ceramic capacitors taken from an-
`tique radios. Early ceramic capacitors looked very much like
`modern examples, although somewhat larger for a given ca-
`pacitance. Then, as now, ceramic capacitors were very reliable.
`Photo courtesy of P. I. Nelson, www.antiqueradio.org, and used
`with permission.
`
`22
`
`IEEE Electrical Insulation Magazine
`
`Petitioner Intel Corp., Ex. 1041
`IPR2023-00783
`
`

`

`Figure 5. Capacitor time line with corresponding cultural time line for reference.
`
`dizing/vaporizing the dielectric and aluminum electrode, ceramic
`dielectrics tend to crack during breakdown, rendering the entire
`device useless. In addition, the internal electrode, typically 0.5
`to 1 µm in thickness, cannot be vaporized readily to isolate the
`breakdown region electrically. The catastrophic failure mode of
`ceramic capacitors is an obstacle to their acceptance for critical
`applications in which a disruption of operation is not acceptable
`or in which the energy stored is so large as to render the capaci-
`tor dangerous upon shorting. Efforts have been made to address
`this issue, such as integrating fuses at MLCC terminations and
`parylene coating on monolithic ceramic capacitors, but success
`has been very limited.
`The abundance of ceramic compounds and the diverse prop-
`erties thereof has resulted in a wide range of materials suited
`to specific applications, a good example of which is the recent
`development of a class of antiferroelectric ceramics with a field-
`dependent phase transition to ferroelectric, as a result of which
`they achieve an energy density greater than 10 J/cc. Some such
`materials have a meta-stable antiferroelectric to ferroelectric
`transition that results in a large dielectric constant under DC
`bias, which makes them an excellent candidate for DC link ca-
`pacitors. Recently, glass-based dielectrics have become a popu-
`lar candidate for high breakdown strength materials. Porosity-
`free ferroelectric glass-ceramics in which ferroelectric particles
`are precipitated from an engineered glass have achieved a break-
`down strength near 100 V/µm, an order of magnitude greater
`than conventional ceramics. As a result of their inorganic nature,
`ceramic capacitors can be formulated to operate at much higher
`temperatures than organic polymer-based dielectrics, which is
`important for applications such as filter capacitors in power elec-
`tronics based on wide band gap semiconductors.
`Polymer films can have Weibull characteristic breakdown
`fields >700 V/µm for test areas of a few square centimeters
`with a Weibull slope parameter in the range of 15, which is
`very good. However, they have low dielectric constants, in the
`range of 2.2 for near-perfect dielectrics such as polypropylene
`and polystyrene and up to 12 for ferroelectric polymers such as
`polyvinylidene fluoride (PVDF), which are far from perfect with
`tan(δ) in the range of 1%. Thus, the emphasis in this technology
`is greater dielectric constant and, if possible, greater dielectric
`
`strength. Promising developments have been reported based on
`copolymers of PVDF that are ferroelectric relaxors. Of polymer
`films, only PET is well suited to low-voltage capacitors because
`it can be made to less than 0.5 µm in thickness. Polypropyl-
`ene, which along with PET dominates film capacitors, cannot be
`made thinner than about 3 µm, which, given its breakdown field
`in the range of 700 V/µm, means it is not well matched to low-
`voltage applications. The other major advantage of metalized
`polymer film capacitors is graceful failure that results from self-
`clearing. This allows operation at increased field because break-
`down of the polymer film results in only a minute reduction in
`capacitance rather than catastrophic failure of the capacitor as is
`the case with foil-based or ceramic-based designs. Self-clearing
`comes at the cost of a number of complications, including a wire
`arc metal spray end connection that has limited current-carrying
`capability, the improvement of which is an area of active inves-
`tigation.
`For very high-voltage applications, metalized film capacitors
`can be made with multiple sections in series across the film. This
`facilitates fairly compact, high-voltage capacitors; however, a
`great deal of volume is wasted as a result of the margins required
`between the sections so that high energy density in such designs
`is unlikely. For fast pulse discharge applications, the end con-
`nections of such designs often limit the peak current output.
`Foil-film designs dominate capacitors used for reactive com-
`pensation in utility power systems, although designs based on
`metalized film capacitors are available. Foil-film capacitors can
`achieve very high power density, i.e., very large current discharge
`over very short times, because they can be designed with low
`equivalent series inductance, very low equivalent series resis-
`tance (ESR), and unlimited end-connection current density. The
`energy density is limited by the need for conservative operating
`fields because the system is not self-clearing. Foil-film technol-
`ogy can be used to make extremely compact, high-voltage ca-
`pacitors through the use of multiple sections in series within the
`winding. Unlike the case of metalized film capacitors, this can
`be done with very little wasted volume because the margin be-
`tween sections runs across the film in the longitudinal direction
`(film width) rather than in the winding direction (film length) as
`for metalized film capacitors. In such a multiple-sections foil de-
`
`January/February — Vol. 26, No. 1
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`23
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`Petitioner Intel Corp., Ex. 1041
`IPR2023-00783
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`

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`sign, the winding connections must be made at the center (to the
`first foil) and at the outer radius (to the last foil), which means
`that the current spirals between the 2 connections, which cre-
`ates substantial inductance. Thus, the self-resonant frequency of
`such capacitors can be very low (100s of kHz) relative to other
`designs.
`Aluminum electrolytic capacitor technology tends to be fairly
`mature, although the size of electrolytic capacitors has dropped
`substantially over the years, especially for the lower voltages.
`The maximum voltage rating of Al electrolytic capacitors has
`also increased slightly. Aluminum electrolytic capacitors have
`several limitations other than the obvious one of being unipolar
`unless operated in series. They have substantial leakage current,
`as a result of which they are rarely used in series to achieve
`higher voltage. The maximum operating voltage is limited to be-
`low 1 kV by the inability to grow the aluminum oxide coating
`sufficiently thick.
`Solid tantalum electrolytic capacitor technology is less ma-
`ture, which has resulted in greater changes, including reduced
`ESR and the use of conducting polymer electrolyte in some de-
`signs. Nevertheless, solid tantalum capacitors tend to have high
`ESR as a result of the solid electrolyte that makes contact with
`the tantalum oxide dielectric and replaces the liquid in the alu-
`minum electrolytic capacitor. Solid electrolytes generally have
`lower conductivity than liquids.
`In the past, double-layer or electrochemical capacitors tended
`to live in a world of their own because their electrical proper-
`ties differ greatly from traditional capacitors. Electrochemical
`capacitors are based on the electric double-layer capacitance
`formed between ionic and electronic conductors, which results
`in capacitance per unit volume or weight that is unmatched by
`any other technology; yet, they are unsuitable for ac filtering be-
`cause they cannot charge and discharge at 60 Hz. However, they
`can charge and discharge more rapidly than batteries. As a result,
`double-layer capacitors are often used to complement batteries
`in applications that have rapidly varying loads such as those en-
`countered in electric and hybrid electric vehicles. Double-layer
`capacitors can also be used as a battery replacement in some
`applications. Compared with conventional capacitors, double-
`layer capacitors have limited life at elevated temperature, which
`is often as low as 1,000 hours at 70 or 85°C. Nevertheless, their
`life at elevated temperature exceeds that offered by alternative
`technologies having comparable or greater energy density, such
`as secondary batteries. Thus, double-layer capacitors have their
`own spectrum of optimal applications that component engineers
`are only beginning to exploit.
`
`Outlook
`Electrostatic capacitor technology has evolved substan-
`tially in terms of materials and quality of those materials. The
`widespread commercialization of self-clearing, metalized film
`capacitors was a major advance, although as discussed earlier,
`the concept of self-clearing goes back to around 1900. The en-
`ergy density of millisecond time scale pulse discharge capaci-
`tors based on metalized film is over 2 J/cm3 for capacitors that
`can sustain very large numbers of discharges, and somewhat
`more for capacitors with limited time at charge and numbers
`
`of discharges. The importance of self-clearing and the result-
`ing graceful failure is sometimes not appreciated fully. Graceful
`failure is essential for any capacitor that stores large amounts of
`energy because the alternative is explosive failure, which is haz-
`ardous. In addition to the improve ments brought by metalized
`film, high-temperature film dielectrics have been developed that
`facilitate wave soldering of circuit boards, down-hole applica-
`tions in the oil industry, etc.
`Ceramic capacitors have come a long way from their begin-
`ning, with a wide range of formulations varying from very high
`dielectric constant, but typically with large field and temperature
`dependence, to formulations for precision capacitors with a very
`low temperature coefficient. At present, barium titanate–based
`MLCC are the mainstay in microelectronics, while specialty
`ceramic capacitors with high temperature stability, high volt-
`age, and/or ultra-high capacitance are being used throughout the
`electronics industry. Innovations in materials technology contin-
`ue to move the ceramic capacitor technology forward. Ceramic
`compositions and processing that yield improved breakdown
`strength, energy density, and operating temperature range will
`be the focus for the foreseeable future. Research to incorporate
`graceful failure into ceramic capacitor technology is also under-
`way.
`Electrolytic capacitors have become the mainstay of power
`supply filtering; however, their limited operating temperature
`range poses a problem for future high power density electronics
`based on wide band gap semiconductors. As a result, research is
`ongoing to develop alternatives for such applications.
`Double-layer capacitors were originally a solution looking
`for a problem because they do not filter and, thus, are un-capac-
`itor-like and because they store little energy and, thus, are un-
`battery-like. With increasing electrification of technology, for
`example in transportation, double-layer capacitors have become
`a widely used capacitor component. Energy storage has become
`increasingly important, and double-layer capacitor technology
`has seen an ever-expanding role in applications involving en-
`ergy conservation, electric power load leveling, and high-power
`millisecond-to-second-long pulse delivery, engine starting being
`but one important example.
`The need for improved capacitor technology is imperative
`as our world becomes increasingly electrified. For example,
`transportation, which has long been the domain of petroleum-
`based internal combustion, is rapidly moving to hybrid electric
`and toward all electric. Advanced low-voltage capacitors are
`needed to facilitate more power-efficient and compact portable
`electronic devices for communications, medical applications,
`and high-power electronics. Applications include implantable
`defibrillators and power electronics for power conversion and
`distribution in hybrid electric propulsion systems. Advanced
`high-voltage capacitors are needed for reactive compensation of
`electric power systems, energy storage and distribution related
`to the interfacing of renewable energy sources to the power grid,
`and for energy storage for pulsed power applications such as
`electromagnetic-based pulse power systems. To meet the pres-
`ent and future demand, substantial advances beyond the present
`state-of-the-art in dielectric materials and capacitor technology
`are required. Higher energy density dielectric materials that en-
`
`24
`
`IEEE Electrical Insulation Magazine
`
`Petitioner Intel Corp., Ex. 1041
`IPR2023-00783
`
`

`

`able the fabrication of capacitors that can operate at tempera-
`tures above 150°C and can handle high-voltage and high-ripple
`current at frequencies over 20 kHz for power electronics are not
`presently available. Technology for fabricating compact, high-
`voltage, high-current, high-repetition-rate capacitors that deliver
`energy in sub-microseconds is also needed.
`In the remainder of this series we will have detailed intro-
`ductions to the various capacitor technologies followed by pa-
`pers that get into various aspects of the technical details of those
`technologies. Looking forward, we hope this series will serve as
`a baseline and foundation for future development.
`
`Acknowledgments
`The authors are pleased to acknowledge the contributions
`of Mr. William Harris of Colorado Springs, CO, retired from
`IBM and an expert on early radios and the components therein,
`nbcblue@hotmail.com. Figure 2 was contributed by Mr. Har-
`ris. Mr. Philip I. Nelson kindly allowed use of photographs of
`old capacitors (Figures 1, 3, 4) from his antique radio Web site,
`www.antiqueradio.org. Mr. John Miller of JME, Inc. provided
`valuable input to the text on double-layer capacitors, as did Dr.
`Ming-Jen Pan of the Naval Research Laboratory in the area of
`ceramic capacitors.
`
`[2]
`
`References
`[1] G. W. A. Dummer, Electronic Inventions and Discoveries, 4th ed. Bristol,
`UK: Institute of Physics Publishing, 1997, p. 74.
`I. B. Cohen, Dictionary of Scientific Biography, vol. 5, C.C. Gillispie, Ed.
`New York: Charles Scribner’s Sons, 1972, p. 129.
`[3] D. G. Fitzgerald, “Improvements in electrical condensers or accumula-
`tors,” British Patent No. 3466/1876, Sept. 2, 1876.
`[4] S. Niwa and Y. Taketani, “Development of new series of aluminium solid
`capacitors with organic semiconductive electrolyte (OS-CON),” J. Power
`Sources, vol. 60, 1996, pp. 165–171.
`[5] G. F. Mansbridge, British Patent No. 19,451, 1900.
`[6] G. F. Mansbridge, “The manufacture of electrical condensers,” J. IEE,
`vol. 41, Oct., 1908, p. 535.
`[7] D. A. McLean, “Metalized paper for capacitors,” Proc. IRE, vol. 38, no.
`9, 1950, pp. 1010–1014.
`[8] D. A. McLean and H.G. Wehe, “Miniature lacquer film capacitors,” Proc.
`IRE, vol. 42, no. 12, 1954, pp. 1799–1805.
`
`[9]
`
`J. H. Cozens. “Development of plastic dielectric capacitors,” IRE Trans.
`Compon. Parts, vol. CP-6, no. 2, 1959, pp. 114–118.
`
`Janet Ho was graduated with a BS in chemical engineering
`from the University of California, Berkeley, in 1995. She spent
`5 years working in the field of polymeric ophthalmic lenses. In
`2000, she joined the Polymer Science Program at the University
`of Connecticut in pursuit of a doctorate, which she completed
`in 2006. She is currently a research engineer with the Army Re-
`search Laboratory in Adelphi, MD, working in the area of capac-
`itor technology and can be reached at janet.ho@arl.army.mil.
`
`T. Richard Jow is a team leader on energy storage at the
`Army Research Laboratory developing high power density bat-
`teries and high energy density capacitors. His main focuses
`include electrolytes, electrode materials, dielectric materials
`development, and technologies for energy storage devices devel-
`opment. Dr. Jow has over 30 years of experience in these areas
`and has authored and coauthored more than 110 publications
`and 19 patents. He received his PhD in materials science and
`engineering from Northwestern University.
`
`Steven Boggs (F’92) was graduated with a BA from Reed
`College in 1968 and received his PhD and MBA degrees from
`the University of Toronto in 1972 and 1987, respectively. He
`spent 12 years with the Research Division of Ontario Hydro.
`In 1992, he was elected an IEEE Fellow for his contributions to
`understanding of SF6-insulated systems. From 1987 to 1993, he
`was director of research and engineering at Underground Sys-
`tems, Inc. He is currently director of the Electrical Insulation
`Research Center and research professor of materials science,
`electrical engineering, and physics at the University of Connect-
`icut, as well as an adjunct professor of electrical and computer
`engineering at the University of Toronto.
`
`January/February — Vol. 26, No. 1
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`25
`
`Petitioner Intel Corp., Ex. 1041
`IPR2023-00783
`
`