1850 IEEE TRANSACTIONS ON COMPONENTS, PACKAGING AND ... · 1852 IEEE TRANSACTIONS ON COMPONENTS, PACKAGING AND MANUFACTURING TECHNOLOGY, VOL. 5, NO. 12, DECEMBER 2015 Fig. 3. Field

1850 IEEE TRANSACTIONS ON COMPONENTS, PACKAGING AND MANUFACTURING TECHNOLOGY, VOL. 5, NO. 12, DECEMBER 2015

RF Characterization of Magnetodielectric MaterialUsing Cavity Perturbation Technique

Kyu Han, Madhavan Swaminathan, Fellow, IEEE, Raj Pulugurtha, Himani Sharma,Rao Tummala, Fellow, IEEE, Brandon M. Rawlings, and Vijay Nair, Fellow, IEEE

Abstract— Magnetodielectric (MD) materials find applicationin many areas of microwave engineering, and therefore,measurement of their dielectric and magnetic properties is veryimportant. This paper presents a novel MD material character-ization method using the cavity perturbation technique (CPT)with substrate-integrated waveguide (SIW) cavity resonators.Frequency dependent complex permittivity and permeability ofMD material can be extracted with a single SIW cavity structureby inserting the sample material into different locations. Thefundamental theory of CPT is explained and its analysis forSIW cavity is discussed. Cobalt nanoparticles are synthesizedwith a fluoropolymer matrix to realize the MD materials and theirproperties are measured in the frequency range 1–4 GHz. Theeffect of volume fraction and density of the synthesized MD mate-rials on the dielectric and magnetic properties has been studied.

Index Terms— Characterization, complex permeability,complex permittivity, extraction, magnetodielectric (MD)material, miniaturization.

I. INTRODUCTION

TODAY’S global trends in mobile industry is smaller,lighter, and thinner devices. Many RF engineers are

working on part miniaturization to satisfy these increasingdemands. Antenna size is an important factor for reduc-ing the overall size of the mobile device. Some mobiledevices have multiple antennas in one device in order totranslate signals in a different frequency range such asGlobal System for Mobile Communications 850/900 MHz orLong-Term Evolution 1700/2100 MHz at once, and there-fore, a small antenna with good performance is necessary.Decreasing the antenna size is very challenging becausethe antenna size is determined by its electrical length andthe antenna performance is also bounded by fundamen-tal limits depending on the size. One method for reduc-ing the antenna size is by changing the geometry of theantenna. By bending or meandering the current path of

Manuscript received December 5, 2014; revised June 29, 2015; acceptedJuly 12, 2015. Date of publication November 19, 2015; date of current versionDecember 11, 2015. Recommended for publication by Associate Editor S. Royupon evaluation of reviewers’ comments.

K. Han is with ViaSat, Duluth, GA 30096 USA (e-mail: [email protected]).

M. Swaminathan, R. Pulugurtha, H. Sharma, and R. Tummala are withthe Georgia Institute of Technology, Atlanta, GA 30332 USA (e-mail:[email protected]; [email protected];[email protected]; [email protected]).

B. M. Rawlings and V. Nair are with Intel Corporation, Chandler, AZ 85226USA (e-mail:[email protected]; [email protected]).

Color versions of one or more of the figures in this paper are availableonline at http://ieeexplore.ieee.org.

Digital Object Identifier 10.1109/TCPMT.2015.2465383

antenna, total area or volume can be decreased. Anothercommon method for antenna miniaturization is to increasethe relative permittivity εr = ε′

r − jε′′r of the substrate

since the antenna size is inversely proportional to (εrμr )1/2,

where μr = μ′r − jμ′′

r is the relative permeability [1].However, increasing εr of the substrate results in increase instored electric energy inside the substrate, which leads to anarrow bandwidth and low efficiency [2]. On the contrary,magnetodielectric (MD) materials that have εr and μr greaterthan 1 can be used to miniaturize antenna size withoutdeteriorating antenna performance too much [3]. Furthermore,by increasing μr/εr ratio, the antenna performance can beimproved more with the same size of antenna [4]. This is justone application of MD materials discussed in this paper.

MD materials have to be realized through material synthesiswhere magnetic metal particles are combined with dielectricmaterials, since they are not available readily in nature.As new composites are synthesized and antenna response isdetermined by the frequency dependent properties (ε′

r , ε′′r ,

μ′r , and μ′′

r ) of the material, an accurate measurement methodis required to extract them. Separating the dielectric propertiesfrom the magnetic properties during measurement can bechallenging and this has been achieved by using two separatestructures in [5] and [6]. One of them is mostly sensitiveto the change in dielectric properties while the other issensitive to the change in magnetic properties. The methoddiscussed in this paper is an extension of [7], where a cavityperturbation technique (CPT) method has been applied fordielectric material characterization using substrate-integratedwaveguide (SIW) cavity. Han et al. [8], [9] introduced theCPT that can be used to extract both electric and magneticproperties with a single SIW structure. Simulations andmeasurements were performed to demonstrate this technique.This paper is a significant extension of [8] and [9] wherenew data are provided for the measured samples along witherror bars. The effects of both metal loading and materialdensity have also been discussed in this paper, which were notprovided in [8] and [9]. In addition, analysis of the anisotropicproperty of composite material along with details of samplesize has been presented in this paper. Furthermore, details ondesigning and exciting the cavity are provided in this paper.

This paper is organized as follows. Section II presentsCPT formulas for permittivity and permeability characteri-zation using SIW cavity. This is followed with design andsimulation of SIW cavities, which is presented in Section III.In Section IV, the details of SIW cavity fabrication and

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HAN et al.: RF CHARACTERIZATION OF MD MATERIAL USING CPT 1851

Fig. 1. Small material perturbation. (a) Original cavity. (b) Perturbed cavity.

measurements of standard samples are presented. Section Vintroduces material synthesis and MD composite samplecharacterization and analysis. Anisotropic material behaviorand measurement are considered in Section VI. Section VIshows the effect of air gap in the SIW cavity duringmeasurements. Finally, Section VII concludes this paper.

II. CPT FOR MAGNETODIELECTRIC

MATERIAL CHARACTERIZATION

CPT material characterization method has been widely usedfor extracting electromagnetic (EM) properties of variousmaterials. It works well for the measurement of low-lossand medium-loss materials; however, this method is lessuseful for extremely low-loss samples [10]. Since synthesizedMD materials usually show moderate loss and the lossincreases as the frequency increases, this method is valid forcharacterizing the MD materials. In the resonant perturbationmethod, the sample is inserted into a resonator, and theproperties of the samples are calculated from changes inthe resonant frequency and quality factor of the resonatorcaused by the sample. The fundamental expression of CPTis [10], [11]

f2 − f1

f1= −

∫Vs

(�εE2 · E∗

1 + �μH2 · H ∗1

)dV

∫Vc

(ε1 E2 · E∗

1 + μ1 H2 · H ∗1

)dV

(1)

with

�ε = ε2 − ε1 (2)

�μ = μ2 − μ1 (3)

where f1 and f2 are the resonant frequencies before andafter the introduction of the sample, as shown in Fig. 1.In (2) and (3), ε1 and ε2 are the complex permittivities ofthe original medium in the cavity and sample, respectively,and μ1 and μ2 are the complex permeabilities of the originalmedium in the cavity and sample, respectively. Likewise,E1 and E2 are the electric fields in the cavity before andafter perturbation, and H1 and H2 are the magnetic fields inthe cavity before and after perturbation, respectively. In (1),Vc and Vs are the volumes of the cavity and sample,respectively.

For complex permittivity measurement, the sample isintroduced where the electric field is maximum in the cavity.From [7], (1) can be rewritten as modified CPT formulas as

ε′s = Aε′

r Vc

Vs

(fo − fs

fs

)

+ ε′r (4)

ε′′s = BVc

Vs

(ε′2

r + ε′′2r

ε′r

) (Qo − Qs

Qs Qo

)

+ ε′sε

′′r

ε′r

(5)

Fig. 2. Details of SIW cavity resonator. (a) Perspective view. (b) Top view.(c) Corner-to-corner probing.

where ε′s and ε′′

s correspond to real and imaginary permittiv-ities of the sample, respectively, and ε′

r and ε′′r are the real

and imaginary parts of the relative permittivity of the cavitymedium. Qo and Qs are the quality factors of the empty cavityand the cavity with loaded sample, respectively. fo and fs

are the resonant frequencies before and after the sampleperturbation, respectively. In (4) and (5), constants A and Bare obtained through calibration using a standard samplewith known permittivity. Similarly, for complex permeabilitymeasurement, the sample is inserted where the magnetic fieldis maximum in the cavity and (6) and (7) can be used forcalculating the complex permeability [10]

μ′s = CVc

Vs

(fo − fs

fs

)

+ 1 (6)

μ′′s = DVc

Vs

(Qo − Qs

Qs Qo

)

(7)

where μ′s and μ′′

s are real and imaginary parts of permeabilityof the inserted sample. Constants C and D in (6) and (7) arealso obtained from the measurement of standard sample ofstandard permeability.

III. SIW CAVITY DESIGN AND SIMULATION

In this paper, SIW technology was used to fabricate thecavity for CPT measurements. SIW has been realized usinga planar substrate and it has been used to measure complexpermittivity of liquid and dielectric materials in [7] and [12]with the advantage of obtaining high accuracy from highquality factor, low profile, and minimum radiation effect.In this paper, we extend this method for measuringMD materials. As shown in Fig. 2, the resonant frequencyof TEm0k mode in an SIW cavity is given by [7]

fr = c

2√

ε′rμ

′r

√(m

Weff

)2

+(

k

Leff

)2

(8)

where c is the speed of light in free space, ε′r and μ′

r arethe relative permittivity and permeability of SIW substratemedium, respectively, and m and k are the operation


Fig. 3. Field distribution of TE103 SIW cavity resonator and sample insertionlocation. (a) E-field. (b) H -field.

Fig. 4. Field distribution of TE102 SIW cavity resonator and sample insertionlocation. (a) E-field. (b) H -field.

mode numbers. Weff and Leff represent the effective widthand the effective length of the cavity, respectively. Vias, withradius r , are used as the via fence with a spacing d . Theeffective width and length Weff and Leff are given by [7]

Weff = W − 4r2

0.95d(9)

Leff = L − 4r2

0.95d. (10)

The resonators are excited at one of the maximum positionsof the electric field in the cavity. A corner-to-cornerprobing method is applied for the excitation. As shownin Fig. 2(b) and (c), a square patch with length a is patternedon the top plane with a gap and the signal tip of ground-signal-ground (GSG) probe is placed on the corner of thesquare patch with ground tips of the GSG probe on eitherside of the top plane. The corner-to-corner probing enablesthe excitation of TEm0k mode in the cavity. The size of thegap is determined by the pitch of GSG probe and the length ais optimized to maximize matching the resonance for theindividual resonators. The SIW cavities can be designed witheither TE102 or TE103 resonant mode where TE102 mode canbe used to measure material properties in the low frequencyrange since it can reduce the cavity dimensions as shownin Figs. 3 and 4. Figs. 3 and 4 show the electric and magnetic

field distributions of the SIW cavity at 2 GHz with TE103resonant mode and 2.5 GHz with TE102 resonant mode,respectively. Light (red) and dark (blue) regions representthe highest and lowest amplitudes of field, respectively. Forcomplex permittivity measurement, the sample is insertedat one of the maximum positions of the electric field, asshown in Figs. 3(a) and 4(a), and for complex permeabilitymeasurement, the sample is inserted at one of the maximumpositions of the magnetic field, as shown in Figs. 3(b) and 4(b).

In the CPT, introducing the sample at either theE- or H -field maximum position changes the resonantfrequency and quality factor of the SIW cavity based on thesample’s complex permittivity or permeability, respectively.During measurements, it is required that dielectric propertiesof the sample does not affect complex permeabilitymeasurement while magnetic properties of the sample doesnot affect complex permittivity measurement. To see the effectof dielectric and magnetic properties on complex permittivityand/or permeability measurement, 3-D EM simulation withCST microwave studio [13] has been used. An SIW cavityresonator using Rogers 3003 material [14] with ε′

r = 3and tanδ = 0.0013 is modeled at 2 GHz with TE103resonant mode to analyze the CPT using SIW. Thicknessof the substrate is 1.52 mm. Cuboid sample with dimensionof 6 mm × 6 mm × 1.52 mm is inserted and its originalmaterial properties are ε′

r = 7 and μ′r = 2 with electric

loss tangent (tanδe = ε′′r /ε′

r ) and magnetic loss tangent(tanδm = μ′′

r /μ′r ) of 0.01 and 0.01, respectively. The

ε′r and μ′

r of the sample have varied between 6–8 and 1–3,respectively, to see their effect on resonance. Similarly tanδe

and tanδm have also varied between 0.01–0.03 and 0.05–0.3 tosee their effect on Q-factor. Q-factor is determined by 3-dBbandwidth of return loss. Changes in resonance and Q-factorbased on the variations are listed in Table I. When thesample is inserted in the electric field maximum, variations ofmagnetic properties do not affect the resonance and Q-factorof the cavity. Similarly, when the sample is located in themagnetic field maximum, dielectric properties of the sampleare not sensitive to changing the resonance and Q-factor ofthe cavity, as shown in Table I. Therefore, it can be concludedthat the CPT using SIW cavities can be used to characterizenot only dielectric materials but also MD materials with asingle structure using different sample locations.

IV. SIW CAVITY FABRICATION AND MEASUREMENTS

In order to measure frequency dependent complexpermittivity and permeability of the MD material,seven SIW cavity resonators were designed and fabricatedwith Rogers 3003 material, which was used for simulationin the previous section, to characterize the sample in thefrequency range 1–4 GHz. Fig. 5 shows the fabricatedSIW cavity resonators, and Table II shows their operatingmode, resonant frequency, dimension, and sample distancefrom the center of SIW cavity. A 6 mm × 6 mm square holewas drilled for sample insertion, as shown in Fig. 5. TheSIW cavity resonator in Fig. 6(a) has a hole at the E-fieldmaximum position for permittivity measurement and anotherresonator in Fig. 6(b) has a hole at the H -field maximum


TABLE I

SIW CAVITY RESPONSE AS VARYING PERMITTIVITY/PERMEABILITY WITH DIFFERENT SAMPLE LOCATIONS

Fig. 5. SIW cavity resonators.

TABLE II

SIW CAVITY RESONATOR SPECIFICATION FOR FIGS. 2–4 (mm)

position for permeability measurement. The position of bothE- and H -field maximum position for sample insertion isdetermined from simulation of E- and H -field distributioninside the cavities and summarized in Table II. Fig. 7shows a picture of the corner-to-corner probe for cavityexcitation.

Rogers dielectric material RO4360G2 [14] was chosenas the standard sample to obtain the constants A and Bin (4) and (5) for each frequency while Cuming MicrowaveFLX-16 [15] magnetic absorber material was used toobtain the constants C and D in (6) and (7). All sampleswere prepared in a cuboid form with dimension of6 mm × 6 mm × 1.52 mm, which is the same dimensionthat was used in the EM simulation. The cavity resonatorswere tested with a vector network analyzer using short,open, load, and thrus calibration. Fig. 6 shows the

Fig. 6. 3.5-GHz SIW cavity resonators with different hole locations for(a) permittivity and (b) permeability measurements.

Fig. 7. Corner-to-corner probe excitation.

corner-to-corner probing method for excitation andmeasurement. Samples were inserted in the hole andcopper tape was used to cover the top and bottom of thesample. GSG 500 probe from Cascade Microtech was usedfor the measurement.

The steps of the material property extraction process can besummarized as follows.

1) For permittivity measurement, insert RO3003 sample(the same material as the SIW substrate) into SIW whichhas a hole at the E-field maximum and cover it with acopper tape.


TABLE III

EXTRACTED PERMITTIVITY AND PERMEABILITY OF SAMPLE MATERIALS USING MEASUREMENTS OF 2-GHz CAVITY

Fig. 8. SIW cavity resonator measurements with various samples. (a) E-fieldmaximum position. (b) H -field maximum position.

2) Measure the return loss (S11) of the perturbedSIW cavity to obtain f0 and Q0 in (4) and (5).

3) Replace RO3003 sample with a standard dielectricsample (RO4360G2 for this paper) and measure thereturn loss to obtain fs and Qs in (4) and (5).

4) Substitute measured f0, fs , Q0, and Qs intoCPT equations, and find the constants A and Bin (4) and (5) by matching calculated ε′

r and tanδe withthe properties of the standard sample.

5) Repeat the return loss measurements for other sampleswhose properties are well known for validation.

6) Use the measured data to calculate the material proper-ties and obtain a percentage error of the measurementby comparing the result with theoretical values providedby material suppliers.

7) Repeat steps 1–6 with SIW cavity which has the holeat the H -field maximum for permeability measurement.Find the constants C and D in (6) and (7) with standardMD sample (FLX-16 for this paper).

Fig. 8 shows return loss measurement of SIW cavity(unloaded resonance at 2.5 GHz), with various samples ofdifferent permittivity and permeability properties inserted inthe hole. As shown in Fig. 8(a), the sample with higherpermittivity shows lower resonant frequency of SIW cavity.It can also be observed that the sample with higherloss shows wider 3-dB bandwidth which corresponds to alower Q-factor. The resonant frequency and Q-factor ofSIW cavity were changed negligibly when dielectric materialsamples were inserted in the H -field maximum position asshown in Fig. 8(b). The magnetic absorber material FLX-16,

Fig. 9. (a) Picture of synthesized MD samples. (b) TEM image of cobalt influoropolymer matrix [20].

which has a permeability greater than 1 produces significantchanges in the resonant frequency as well as the Q-factor ofSIW cavity. Table III shows the measured material propertiesusing the proposed the CPT using SIW cavity (unloadedresonance at 2 GHz). Both permittivity and permeability havebeen extracted and the results show that the measurementsare very close to the theoretical values provided by materialsuppliers. The permittivity values of standard samples frommaterial provider are very limited. Therefore, it is assumed thatthe permittivity of the standard sample is constant as providedby the supplier over the frequency range up to 4 GHz forthis paper. Error percentage of this method is obtained fromthese measurements by comparing the results with the valuesprovided by the supplier for each frequency.

V. MAGNETODIELECTRIC COMPOSITE SYNTHESIS

AND PROPERTIES EXTRACTION

In this paper, metal–polymer (cobalt–fluoropolymer)nanocomposite materials were synthesized to realize theMD material [18], as shown in Fig. 9(a). SynthesizingMD material having high permeability and low loss at highfrequency is challenging and it can be achieved by reducingthe particle size and separation between adjacent metalparticles down to the nanoscale [19]. The metal particles weremilled with a dispersant in propylene glycol methyl etheracetate as the solvent medium and it was followed by anothermilling process with the polymer solution. After this millingprocess, the metal particle size was reduced to 20–30 nmand a metal–monomer slurry was produced. Transmission


Fig. 10. Extracted properties of MD samples A–C. (a) ε′r . (b) tanδe. (c) μr . (d) tanδm .

TABLE IV

MEASURED RESONANCE AND Q-FACTOR BEFORE AND AFTER

SAMPLE INSERTION (2-GHz SIW)

Electron Microscopy image of cobalt nanoparticles in thefinal nanocomposite is shown in Fig. 9(b) [20]. The metal–monomer slurry was dried in a nitrogen oven to make apowder and excess solvent was evaporated. Dried powderwas inserted in a die with size 6 mm × 6 mm and pressedwith a uniaxial pressure to make the cuboid sample. Theheight of the MD sample was also controlled to have a heightof 1.52 mm.

In this paper, three MD material samples with differentmetal loading percentages 30%, 50%, and 70% weresynthesized in order to study the relationship betweenmetal loading percentage in the composite material andthe resulting material properties. Samples A–C represent30%, 50%, and 70% metal loading sample, respectively.

Table IV shows the measured resonance frequencies andQ-factors of the SIW cavity (unloaded resonance at 2 GHz)before and after the samples insertion. Fig. 10 shows theextracted material properties of three MD composites usingthe seven SIW cavity resonators. All three samples show fairlyconstant ε′

r in the frequency range 1–4 GHz but μ′r decreases

as the frequency increases. Sample C shows the highestε′

r and μ′r among the three samples. Sample A shows the

lowest ε′r and μ′

r among the three samples. Sample A showsε′

r of 9.5 and μ′r decreased from 2.18 to 1.7 in the frequency

range 1–4 GHz. Sample B has an ε′r of 11.8 and a μ′

r of 2.18at 1 GHz and 1.8 at 4 GHz. Sample C shows an ε′

r of 13.2and a μ′

r of 2.7 at 1 GHz and 2.1 at 4 GHz. As shownin Fig. 10, higher metal loading composite material showshigher loss for both tanδe and tanδm than lower metal loadingcomposite material. Changes in tanδe were small but tanδm

significantly increased as the frequency increased. For tanδe,samples A–C have values of 0.004 ± 0.0005, 0.004 ± 0.001,and 0.005 ± 0.0005, respectively. For tanδm , samples A–Chave 0.018 ± 0.001, 0.061 ± 0.003, and 0.084 ± 0.004at 1 GHz, respectively. According to Snoek’s law [21], higherinitial permeability lowers ferromagnetic resonance, which isrelated to higher magnetic loss. This explains why the higherμ′

r sample shows higher tanδm . The extracted data have beenshown to satisfy Kramers–Kronig relationship in [22].

Another sample B′, which has 50% metal loading, butlower density than sample B, was also synthesized to studythe relationship between the density of composite material


Fig. 11. Extracted properties of MD samples B and B′. (a) ε′r . (b) tanδe. (c) μr . (d) tanδm .

Fig. 12. Simulation and measurement of return loss of cavity with sample B inserted. (a) Permittivity. (b) Permeability.

and the resulting material properties. The densities ofsamples B and B′ were 3.65 and 2.75 g/cm3, respectively.Fig. 11 shows the comparison between extracted materialproperties of samples B and B′. Sample B′ showsε′

r = 6.5 ± 0.2 and μ′r decreased from 1.8 to 1.4 in

the frequency range 1–4 GHz. Comparing samples B and B′,lower density sample B′ has lower ε′

r and μ′r than sample B.

Lower density nanocomposite can have higher porosity inthe composite than higher density composite and this cancause increased distance between metal particles therebydecreasing both permittivity and permeability. From this,it can be concluded that MD, using metal–polymer systemwith desired permittivity and permeability values can besynthesized by optimizing metal loading percentage and


Fig. 13. Effect of air gap to measurement error.

density of nanocomposite material. Details on the mixingrules and resulting material properties are described in [22].

To validate these extracted properties, SIW cavitymeasurements were compared to CST simulations. Extractedproperties of complex permittivity and permeability were usedin CST for simulating the return loss of the SIW cavity.These simulations were compared to measurements as shownin Fig. 12 for the seven cavities. A feature selective validationtechnique [23]–[25] was used to compare the datasets of sim-ulations and measurements and it gives a good quality of com-parisons. The accuracy of the extracted measurements has beenvalidated based on the resonant frequency of a Planar Inverted-F Antenna which was fabricated and measured suing theMD sample with 50% loading [26]. The results indicate thatthe MD material properties are close to the extracted values.

VI. AIR GAP ANALYSIS

The measurement result of the CPT shownin Sections IV and V assumed that there were no airgaps around the inserted sample. When the sample is insertedinto the hole in the SIW cavity, any air gap around thesample can alter its extracted properties. Hence special carewas taken to ensure that the sample was suitably sized to fitexactly into the cavity. In this section, we analyzed the errorintroduced due to the presence of any air gap, using simulationwith CST. Sample with εr = 7, μr = 2, tanδelec = 0.001, andtanδmag = 0.001 was used for analysis at 2 GHz. Return lossof the SIW cavity with the inserted sample was simulated asthe volume of the sample was decreased. From Fig. 13, it canbe seen that a reduction in sample volume of 5% resulted ina 4.2% error in the extracted relative permittivity. However,a similar reduction in volume resulted in only a 2.5% errorfor the extracted relative permeability.

VII. CONCLUSION

In this paper, a CPT with SIW cavity resonators hasbeen proposed and experimentally investigated to measurefrequency dependent complex permittivity and permeabilityof MD material. A single SIW cavity resonator can be used toextract both properties by changing sample insertion locationinside of the cavity. For complex permittivity measurement,the sample was inserted at the E-field maximum and forcomplex permeability measurement, the sample was insertedat the H -field maximum. The isolation between electric and

magnetic measurement was shown through simulation andexperiment. cobalt–fluoropolymer was used to synthesizeMD material and was measured in the frequencyrange 1–4 GHz in this study. Three different metal loadingcomposites were measured in order to analyze its effectson material properties. As the metal loading in compositeincreased, both real permittivity and permeability valueswere increased as well as the loss was increased. AnotherMD sample with different densities was also synthesizedand characterized. By reducing the density of the sample,the permittivity and permeability decreased even though thesample had the same metal loading percentage. Effect of airgap around inserted sample also analyzed using an EM solverin this paper. The complex permittivity and permeability ofthe cobalt–fluoropolymer MD material reported in this paperare the best reported for any metal–polymer system at 1 GHz.

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Kyu Han received the B.S. degree in electricaland computer engineering from the Universityof Arizona, Tucson, AZ, USA, in 2005, and thePh.D. degree in electrical and computer engineeringfrom the Georgia Institute of Technology, Atlanta,GA, USA, in 2015.

He joined Viasat, Carlsbad, CA, USA, as anAntenna and Microwave Engineer. His currentresearch interests include antenna miniaturizationand magneto-dielectric material characterization.

Madhavan Swaminathan (M’95–SM’98–F’06)received the M.S. and Ph.D. degrees in electricalengineering from Syracuse University, Syracuse,NY, USA, in 1989 and 1991, respectively.

He was a Joseph M. Pettit Professor of Electronicsand Electrical Communication Engineering and theDeputy Director of the NSF Microsystems Pack-aging Research Center with the Georgia Instituteof Technology (Georgia Tech), Atlanta, GA, USA.He was with IBM, Armonk, NY, USA, where hewas involved in packaging for supercomputers.

He was the Founder and Co-Founder of two start-up companies, such asE-System Design, Johns Creek, GA, USA, and Jacket Micro Devices, Atlanta.He is currently the John Pippin Chair in Electromagnetics with the School ofElectrical and Computer Engineering and the Director of the Interconnect andPackaging Center with Georgia Tech. He has authored over 400 refereed tech-nical publications, authored and co-edited three books, and holds 29 patents.

Dr. Swaminathan was the Founder of the International IEEE ElectricalDesign of Advanced Packaging and Systems Conference. He has served as aDistinguished Lecturer of the IEEE Electromagnetic Compatibility Society.

Raj Pulugurtha received the B.S. degreefrom IIT Kanpur, Kanpur, India, in 1993, theM.S. degree from the Indian Institute of Science,Bangalore, India, in 1995, and the Ph.D. degree inceramic engineering from Rutgers University,New Brunswick, NJ, USA, in 1999.

He co-developed several technologies, whichinclude low-cost capacitor and inductor integration,advanced thin film precision analog and RFcomponents with nanomagnetic and nanocompositedielectrics, and their package integration as

functional modules. He is currently a Research Professor and the ProgramManager for the Power and RF Functional Components and Modulesprogram with the 3-D Systems Packaging Research Center (PRC), GeorgiaInstitute of Technology, Atlanta, GA, USA. He provides leadership in theareas of power-supply component integration on silicon, glass, and organicsubstrates for power conversion and integrity, RF and precision components(antennas, diplexers, matching networks, and nonlinear devices), andfine-pitch interconnections with PRC. He has co-authored 215 publications,eight books, and holds eight patents with others pending.

Dr. Pulugurtha received more than 13 best paper awards for his conferenceand journal publications, which include the Distinguished Scholar Awardfrom the Microbeam Analysis Society, the IEEE TRANSACTIONS ON

ADVANCED PACKAGING Commendable Paper Award, the IEEE OutstandingTechnical Paper, the IEEE ECTC Best-Poster Award, and the Philips BestPaper Award. He is the Co-Chair of the IEEE Components, Packaging,and Manufacturing Technology Society (CPMT) Nanopackaging TechnicalCommittee, and the Track Chair of Nanopackaging in the IEEE InternationalConference on Nanotechnology. He is also the Co-Chair and served as theSession Chair of the High-Speed, Wireless & Components Thrust in the IEEECPMT and the IEEE Electronics and Component Technology Conference.

Himani Sharma is currently a Research ProgramManager with the 3-D Systems Packaging ResearchCenter (PRC), Georgia Institute of Technology,Atlanta, GA, USA. She is responsible for the powermodule research and development, in particular,in the area of nanopower components with PRC.She is also actively involved in the developmentalresearch program on component integration on glasssubstrates. She has authored or co-authored severaljournal papers, book chapters, and peer-reviewedconferences.

Dr. Sharma received the 2011 IEEE ECTC Best-Poster Award for her workon high-density capacitors.

Rao Tummala (M’88–SM’90–F’94) was a fellowof IBM Corporation, Armonk, NY, USA, wherehe invented a number of major technologies forIBM’s products for displaying, printing, magneticstorage, and packaging. He was a lead MaterialsScientist pioneering the industry’s first plasmadisplay in the 1970s and the Technical Leader forthe industry’s first low-temperature co-fired ceramicin the 1980s. He is currently a Distinguishedand an Endowed Chair Professor of Electrical andComputer Engineering and Materials Science and

Engineering with the Georgia Institute of Technology, Atlanta, GA, USA.He is also the Founding Director of the NSF Engineering Research Centercalled the Microsystems Packaging Research Center (PRC) pioneering thesystem scaling or Moore’s law for systems by his system-on-package vision.The PRC has been one of the largest and most comprehensive academicmicro-systems packaging research, education and industry collaborationcenters involving more than 100 students and 15 faculty from ECE, ME,ChE and MSE departments, and 70 global companies from the U.S., Europeand Asia. He is also an Eminent Scholar for the state of Georgia. He hasauthored over 400 technical papers, the first modern reference book entitledMicroelectronics Packaging Handbook (1988), and the first undergraduatetextbook in 2001, and holds 71 U.S. patents and inventions.

Prof. Tummala is a fellow of the International Microelectronics Assemblyand Packaging Society and the American Ceramic Society, and a memberof the National Academy of Engineering. He received 30 academic,industry, and professional society awards. He was the President of the IEEEComponents, Packaging, and Manufacturing Technology Society and theInternational Microelectronics and Packaging Society.


Brandon M. Rawlings received the B.S. degree inchemical engineering from the California Instituteof Technology, Pasadena, CA, USA, and thePh.D. degree in chemical engineering from theUniversity of Texas at Austin, Austin, TX, USA.

He joined Intel Corporation, Santa Clara,CA, USA, in 2012, as an Advanced PackagingEngineer. His current research interests includeorganic polymeric packaging materials, photoresists,and electrical, magnetic, and optical functionalmaterials for package integration.

Vijay Nair (F’00) was a Distinguished Memberof the Technical Staff with Motorola Labs, Tempe,AZ, USA. He joined Intel Corporation, Santa Clara,CA, USA, in 2003. He is currently a PrincipalEngineer with Components Research–TMG, SantaClara. He has authored over 120 papers in refereedjournals and presented papers in many internationalconferences and workshops, and holds 22 issuedU.S. patents. He has also authored several chaptersfor technical books and co-authored a book entitledRF and Microwave Circuit and Component Design

for Wireless Systems. His current research interests include small form factorsystem-in-package building block technologies and integration of disparateactive and passive components in low profile packages for notebooks andsmart phones.

Dr. Nair served as a member of the IEEE MTT-Society’s AdministrativeCommittee reporting to the Society President from 2002 to 2012. He was theGeneral Chairman of the IEEE International Microwave Symposium, Phoenix,AZ, USA. The IEEE Microwave Theory and Techniques Society electedhim as a Distinguished Microwave Lecturer for a three-year term in 2007.He gave technical talks in many international forums around the world onHeterogeneous Wireless Communication Devices: Present and Future.

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1850 IEEE TRANSACTIONS ON COMPONENTS, PACKAGING AND ... · 1852 IEEE TRANSACTIONS ON COMPONENTS, PACKAGING AND MANUFACTURING TECHNOLOGY, VOL. 5, NO. 12, DECEMBER 2015 Fig. 3. Field