Effect of membrane wetting on the performance of PVDF and PTFE membranes in the concentration of pomegranate juice through osmotic distillation. 4. Published in: 2006 International Conference on Microwaves, Radar & Wireless CommunicationsFigure 6. If it absorbs energy from loss tangent then you suffer on transmission loss and return loss and hence sensitivity. 0210 IPC-4101 /98 /99 /101 /126 UL - File E41625 Grade PCL-FR-370HR 370HR is the industry's “best in class” lead-free compatible product for high-reliability applications across a wide range of markets. 2–12. 4 %PTFE also has a very low loss tangent with a typical value of tan δ = 4 × 10 −4 , which decreases by a factor of 2-3 from 300 K down to 4 K [51, 52]. CuClad Laminates by Arlon. North America Asia Europe IsoDesign Tools Contact Us. Compos. [Dally] Advanced Board Dielectrics 32 ~1. 23 and 0. This measurement method allows us to determine the permittivity and the loss tangent of homogeneous materials. / Need More Data? What if users need data for a specific grade?To achieve polymer-based composites for electronic packaging with low dielectric constant, low dielectric loss tangent and high thermal conductivity, silane coupling agent KH550 modified hexagonal. PTFE has low dielectric constant ε ′ r ∼ 2. Thermal. However, it is explained in Section. PTFE loss tangent was set to zero, as the realistic loss tangent of PTFE is extremely small anyway, and the shortness of the line further reduces any significant losses in the coaxial line. The basic reason for the relatively high loss tangent exhibited by. 4. Tapes, sheets and finished products can be supplied etched. This page titled 10. The result is a low loss material which can be fabricated using standard epoxy/glass (FR-4) processes offered at a competitive price. Each experimental setup has three main parts: water reservoir, DNAPL reservoir and main column (porous medium). It is possible to create low-cost RF circuit cards on FR-4, but the losses will always be much higher than on PTFE-based boards from reputable suppliers. 3. 3E-4 @3. 2021, 11, x FOR PEER REVIEW 7 of 9 . 1) Specification Sheet (see 1. 4 a–b. 6 to 1. a) Dielectric loss (in dB per unit length, length is in the units used for λ. 2. The ε of the PTFE composite film (PTFE/BN/m-AlN) with 90 wt% filler content was only 3. 6648. These materials have lower loss tangent than FR4 materials, so signals can travel farther without attenuating and still fall within acceptable margins. Additionally, as shown in [14,15] fleece fabric provides sufficient thickness for an adequate bandwidth. 24 3. CuClad laminates feature low dielectric constants (Dk) ranging from 2. 1. 2 for comments on expected behavior for permittivity as a function of frequency. 24. Low loss, low density dielectrics typically range in dielectric constant from 1. The scanned data may also be saved on disk. PTFE Teflon® Type A L=4. The ratio of dissipation to stored energy is defined as tanδ. 4 a–b. Loss Tangent (RC 64%) @10GHz: 0. 031 at 0. The dissipation factor remained constant, being about 2 × 10 −5. from. 11) Reinforcement (see 1. 2. There is also an add-on Material Library product, which contains up to 24 separate material properties and 10,328 materials with more than 84,000. Polymers are important dielectric materials that are often used for a wide range of applications, including high-energy-density capacitors 1,2,3,4,5,6,7,8,9, high-voltage cables 10. The effect of surface treatment on the morphology, thermal conductivity and dielectric properties of PTFE-based composites is investigated. It can be clearly seen that the profile of -NRW in Fig. PTFE is often used in high-frequency and microwave applications due to its low signal loss and superior electrical performance. 5 GHz at room temperature and also for temperatures varying from –30°C to 25°C at a frequency of 3. It is observed that G ′ and G ″ increased at different PTFE concentrations as ω increasing from 0. 25 Of particular concern in many low-temperature measurements is the dc resistance and rf loss, which can create ohmic heating and degradation of quantum information. Since the signal propagation speed and. PTFE is known as non-absorbent (k close to 0), its relative permittivity n=2. PTFE Teflon® Type A L=4. 85*10-12 F/m), ε 0 - dielectric constant of silicon (11. However, the changes of the electrical property (including dielectric constant and loss tangent) are complex and hard to be obtained and analyzed. 66-78. Meanwhile, the dielectric constant and dielectric loss of PTFE/CNT (5 wt%) nanofiber membranes are 58. RT/duroid 5880 laminates has a low dielectric constant (Dk) and low dielectric loss, making them well suited for high frequency/broadband applications. 3). Temperature stable low loss PTFE/rutile composites using secondary polymer. A new kind of ZrTi2O6 filled polytetrafluoroethylene (PTFE) microwave composite substrates was fabricated through the hot-pressing process. Low dielectric loss and low-cost recycled borosilicate (BRS) glass-reinforced polytetrafluoroethylene (PTFE) composites were fabricated for microwave substrate applications. The coefficient of sliding friction between PTFE and many engineering materials is extremely low and when sintered with wear reducing compounds, an industrially important class of bearing materials are formed. Loss tangent (tan (δ)) is a measure of signal loss as the signal propagates down the transmission line. In the present work, fillers having different temperature coefficient of permittivity ( τ ε r ) were incorporated in the PTFE matrix near to the optimum filler loading, and we studied the effect. Permittivity and loss tangent of the composite substrates were measured at X-band frequency region (8. The Lynch formula [1] can be used to predict the change in Loss tangent loss Rule of Thumb #116. For example, teflon (a. 2. See. 1 50-170 - 0. 1. Teflon is the brand name that Dupont Corporation uses for its PTFE materials, and it is so well-known that people use Teflon PCB to refer to PTFE substrate PCBs used for. Because RO4350B is processed using a standard epoxy resin/glass (FR-4) process, it also has a low line processing cost. Most plastics have relatively lower dissipation factor at room temperature. Polytetrafluoroethylene (PTFE) refers to the synthetic fluoropolymer derived from tetrafluoroethylene. 5" Positive slope due mostly to sintered glass. PTFE has become the material of choice where low friction, excellent thermal properties, chemical inertness, and exceptional dielectric properties are required. 00022. BZV-filled HDPE composite shows a εr value of 4. 0021: Industry Approvals IPC-4101 Specification Number: /102 IPC-4101E/102 Validation Services QPL. 2: Loss tangent defined in terms of the real and imaginary components of the complex permittivity [Math Processing Error] ϵ c. 07 and 0. tan (δ) or Df is the result of electromagnetic wave absorption by the dielectric. 7–5. A certain SiC, Si, and PMMA powder mass was weighed. c. 8 and have a loss tangent of 0. SFR can be applied to low-roughness copper foil, whereas PTFE can only. XRD patterns of pure AgNO 3, pure PMMA, pure PVdF, different wt% ratios of PMMA and PVdF with constant AgNO 3 (5 wt%) are shown in Fig. Rick Lovelady. 004 to 0. This family of advanced laminates offers exceptional electrical and mechanical stability. The dielectric loss increases with increasing values of Df. constant of 2. Those values increase with frequency to between about 3. 6 Hz. The metallic parts, i. 44 × 10 −3, respectively, by the improved free-space. 2 dB with a thickness of 2. Appl. It has excellent chemical resistance, is unaffected by. 0 ()1. Compared to traditional dielectric resonator loaded metal cavity method, it has advantage of small sample size (*2–3 orders of magnitude smaller than the old method), and much higher sensitivity to measure small loss tangent values as small as 10-5 at around 7 GHz bandPTFE- substrate” and relatively insensitive to based composites for use as a printed circuit board substrate is designed to provide enhanced heat-transfer through “Best-In-Class” thermal conductivity, while reducing dielectric loss and insertion loss. PTFE is chosen as polymer matrix because of its excellent dielectric properties (low relative permittivity∼2. PTFE-based ceramic-polymer dielectric composites have been widely researched in the communication field due to their good processing, wide range frequency and temperature stability and being able to provide tunable dielectric constant in a scale. Larger error bars due to stability of lab ambient temperature. 44 × 10 −3, respectively, by the improved free-space. 5. 13. Atomic Force Microscopy (AFM) is no longer used as a nanotechnology tool responsible for topography imaging. 008 87 Loss modulus (MPa) 336 ±70 375 ±83 Storage modulus (GPa) 3. 0% BN/PTFE composits in ablation process is 21. This type of PCB stackup is suitable for. PTFE has dielectric constant of 2. These substrates use direct bond copper (DBC. Rutile filled PTFE composites have been fabricated through Sigma Mixing, Extrusion, Calendering and Hot pressing (SMECH) process. 41Speciality grades Higher stiffness grades (separate data sheets available) Grade Process Characteristics Typical applications DELRIN® 510GR Injection DELRIN® 510GR is a 10% glass fibre reinforced, Parts requiring very high strength and stiffness. 45 MPa) and bending modulus (522 MPa), better thermal. 3 and 0. comThe dielectric constant (Dk) of a plastic or dielectric or insulating material can be defined as the ratio of the charge stored in an insulating material placed between two metallic plates to the charge that can be stored when the insulating material is replaced by vacuum or air. • FR-4 Loss Tangent = 0. maximum achievable distance by radar sensor. 6 Thermal stability of AlN/PTFE composites. Polytetrafluoroethylene (PTFE), commercially known as Teflon, is a semi-crystalline fluoropolymer. 18 and 0. 2. 4 for all desired frequencies. Polytetra uoroethylene (PTFE) has an extremely low dielectric constant and dielectric loss tangent among uoropolymers, as well as excellent chemical resistance, weather resistance, and heat. - Suitable for high-frequency electric wires since both the dielectric constant and the dielectric loss tangent are small - Coefficient of friction is so small that it can gain the excellent slipperiness. 0010 to 2. Successful Design of OC-48/2. 5 S/m. 6 for the entire band while loss tangent varies from 0. Loss Tangent @ 1MHz – 0. 5 Repeat 5. Using precision control of the fiberglass/PTFE ratio, CuClad laminates offer a range of choices from the lowest dielectric constant and loss tangent to a more highly reinforced laminate with better dimensional. 1: Permittivity of Some Common Materials is shared under a CC BY-SA 4. Electromagnetic simulations demonstrate that both the resonant frequency and quality factor of the sensor vary considerably with the dielectric constant and loss tangent of the liquid sample. An intermediate layer is often. which are ideal for most of the electronic applications [11]. 46 and 2372. 1Thermally conductive low loss laminate. Loss Tangent (RC64%) 10 GHz (SPC method) 0. The conductivity of PTFE/CNT (5 wt%) nanofiber membranes reached 1. 4 times higher dielectric loss tangent and effective relative dielectric permeability compared to unmodified. If the capacitor is used in an AC circuit, the dissipation factor due to the non-ideal capacitor is expressed as the ratio of the resistive power loss in the ESR to the reactive power oscillating in the capacitor, orThe loss tangent may increase or decrease with increasing temperature depending on the frequency and the moisture content condition, as shown in Fig. At frequencies less than 1kHz the loss tangent of wood above the FSP may decrease sharply as the temperature is reduced below freezing. 5. The surface of SrTiO 3 powders were successfully coated by silane coupling agent (vinyltrimethoxysilane, VTMS). 1 and extremely low loss. TEM transmission line, loss tangent of 0. PTFE-based composites are widely used for the fabrication of microwave circuit boards [3], [4]. 5 RT Duroid RT Duroid is Glass Microfiber Reinforced PTFE (polytetrafluoroethylene) composite produced by Roger Corporation. 1). Materials with a low loss tangent and low relative permittivity are essential for the next. 7 and a loss tangent of. 019 and 0. How-ever, disadvantages of PTFE substrate include a high linear coefficient of thermal expansion (CTE) and low surface en-ergy. 1. 2. Article. maximum achievable distance by radar sensor. , the maximum dielectric loss tangent is 0. 54*10-5. If tanD is zero, there is no loss due to dielectric. Variation of density and dielectric constant with respect to weight fraction of fused silica in the PTFE matrix is shown in Fig. The only way you can reduce it is to use a dielectric with a very low loss tangent, or low dielectric constant. Hao Wang, Hao Wang. In fact, IDTechEx's benchmarking studies in their "Low-loss Materials for 5G and 6G 2023-2033" report finds that commercial PTFE laminates have a loss tangent that is, on average, 6x less than commercial epoxy-based laminates. 008 from 75GHz to 100GHz. Overall, these findings provide a simple and effective route for preparing high-performance NBR composites with large thermal conductivities and dielectric constants. Stretching is more important at lower frequencies and data rates, which affects the trace. 3 GHz and 5. 4" L=10. Unlike PTFE based high performance materials, RO4000 series laminates do not require specialized via preparation processes such as sodium etch. Using PEC as a material with infinite. ( CC BY-SA 4. The shape of PMMA was limited to spherical. 05, high signal loss Tg – 130°C max glass transition temperature Flammability – Self-extinguishes but not fastest suppression. Relative permittivity is the factor by which the electric field between the charges is decreased relative to vacuum. The low loss tangent is a consequence of the symmetrical conformation of the polymer backbone, which effectively neutralizes the dipole forces of the C–F bonds yielding a net zero dipole moment. It is a hemispherical skin of microwave-transparent material of radius R and thickness t, supporting a pressure difference, Δp between its inner and outer surfaces. The formula to calculate the dissipation factor of an insulator is as follows: Where: DF is the dissipation factor or loss tangent; δ is the phase angle between the voltage and current waveforms in the insulator; I R is the resistive current; I C is the. 195" RG 400 Loss (Attenuation) & Power. Over different frequency ranges, PTFE is stable and possess low dielectric constant ɛ r ∼ 2. 02 in this frequency range. 2. Dissipation Factor is a dimensionless measure and hence no units. In fact, IDTechEx's benchmarking studies. 95, 062903 (2009) Article Google Scholar Download. 011: GOOD Dielectric Constant 4. ties such as stable dielectric constant, low loss tangent, and good chemical resistance. 05 (CW) to 2. SrTiO 3 /PB composite exhibits a high dielectric constant of 21. 1 FILTRATION Selecting the Best Filter for Your Application Choosing a filter does not have to be complicated – Corning has simplified the process. Resonac considers the difference between SFR and LCP as the difference in dielectric loss based on Dk and Df. 1), extremely low loss tangent (tg δ = 10 −4 at 1 GHz), corrosion resistance, excellent chemical resistance, and is stable in a wide range of frequencies [8], which make it a. The only way you can reduce it is to use a dielectric with a very low loss tangent, or low dielectric constant. Volume resistivity. 018;. 14) The term tan d is called loss tangent (dissipation factor or loss factor) and it represents Fluoropolymer film provides low-loss dielectric constant loss tangent; Low moisture absorption for consistent performance; RoHS Compliant; The fluoropolymer in Pyralux® TK is chemically similar to the PTFE fluoropolymer utilized in rigid high speed laminates and standard procedures to drill and activate such boards should be applicable. Substrate materials like FR-4 (epoxy resin), PTFE (Polytetrafluoroethylene), Ceramic, and metal core (copper or aluminum) are used. Rogers RO3010 advanced circuit materials are ceramic-filled PTFE composites that offer a higher dielectric constant with excellent stability. Low values of Df result in a “fast” substrate while large values result in a “slow” substrate. 6” • PTFE (Teflon) 25dB loss is 22. Toray's electrically pure, low-loss materials and syntactics ensure maximum radome efficiency. The core materials that they provide constitute properties of high frequency like Teflon (PTFE). Total RF Transmission Line Loss. Figure 7 shows the variation of moisture absorption of PTFE/SiO 2 composites with the mass ratio of small size particle. 2. Some key advantages of PTFE include: Low dielectric constant and loss tangent: PTFE offers a low dielectric constant and low loss tangent, which results in minimal signal loss and distortion at high frequencies. The two critical material properties in determining radome performance are the dielectric constant, ε r, and the electric loss tangent tan δ. 0015 0. 4 plots the storage (G′) and loss (G″) modulus, complex viscosity (η*), and tangent of the phase angle shift (tan δ) against frequency (ω) for PP and its blends, respectively. The values below are relative permittivity for a few. 009 to 0. @ 5 GHz. PTFE), which is commonly used as a dielectric, has a loss tangent of 0. Step 3: Select the correct membrane area to. Sci. The PTFE/PVDF coating (containing 20 wt% of PTFE) exhibits synergistic effect with high water contact angle (CA, 153. fre- Moisture absorption significantly influences electrical properties of the composite since water has high dielectric constant and loss tangent. Relative permittivity is the factor by which the electric field between the charges is decreased relative to vacuum. Loss Tangent 0. 0000 0. Jul 2011;. Dielectric PTFE 0. 4= loss tangent measurements as specified in 5. Because of the high loss tangent, don't try to make any filter structures! Properties of FR-4. This is ideal for applications including automotive radar (77 GHz), advanced driver. Comparing Equation 3. Solid PTFE has a dielectric constant of 2. Where tan δ is the dielectric loss factor of the substrate and f is frequency. 5. 7. 3 to 10. However, the application of PTFE was hindered by its high CTE (∼400 ppm/ o C) due to its room temperature phase transformation. Loss Tangent: A. It can be seen that the PTFE/recycled BRS composite shows a lower dielectric constant, loss tangent, moisture absorption and CTE than the. PTFE loss tangent AFM study: (a). 33 x 107 MΩ-cm 2. The use of composite engineering to tailor structural composite materials for damping results in enhancement of the loss tangent, with negligible, if any, reduction of the storage modulus. Membr. Measurements on PTFE versus frequency have shown that for this material both real part of permittivity and dielectric loss tangent are practically constant in frequency range of 100 MHz-20 GHz. 1885 0. This is first, because the low dissipation factor of the dielectric itself reduces attenuation, especially at higher frequencies, and second the low dielectric constant of a microporous dielectric allows the use of a larger. The dielectric loss tangent of the hBN/PTFE/PDMS composites with (a) no hBN, (b) no PTFE, (c) hBN 40 vol% and (d) PTFE 40 vol% at 18. In an ideal capacitor without any dielectric losses, the insulation current is exactly 90° leading according to the applied voltage. Megtron 6’s electrical properties are competitive with PTFE–based materials, but with improved processability. PTFE also has a very low loss tangent with a typical value of tan δ = 4 × 10 −4 , which decreases by a factor of 2-3 from 300 K down to 4 K [51, 52]. fiber reinforced PTFE laminates yet it has a loss tangent that is lower than traditional chopped fiber reinforced laminates. Dielectric ceramics and substrates are electrical insulators with dielectric strength, dielectric constant and loss tangent values tailored for specific device or circuit applications. 2: Loss tangent defined in terms of the real and imaginary components of the complex permittivity [Math Processing Error] ϵ c. PTFE 2. Polytetrafluoroethylene (PTFE) polymer is an example of a linear fluoropolymer. 1 Understanding Dielectric Constant and Loss tangent on Radome and Antenna Design誘電正接（ゆうでんせいせつ、dissipation factorあるいはLoss tangent）とは、誘電体内での電気エネルギー損失の度合いを表す数値である。 その定義から「タンジェント・デルタ」、あるいは略して「タンデルタ」「タンデル」と呼ぶこともある。PTFE is a semi-crystalline non-polar polymer whose main chain is [CF 2-CF 2] n . The values from the associated chart are obtained by the analysis of both the moulding and extrusion process. Moreover, the PTFE/T-GF exhibited improved dielectric constant (2. It also can be seen that the dielectric loss tangent exhibits strong frequency dependence in the low frequency region (10 2 −10 5 Hz),. 002 at 10 GHz; Low coefficient of thermal expansion. The loss tangent is defined by the angle between the capacitor's impedance vector and the negative reactive axis. = 진공의 유전율 은 진공 상태에서 / 값으로, 다음과 같이. How can I define this new material in CST? It is noteworthy that the material has complex permittivity. 003 at 10GHz. In the design of the. The PTFE/CNT (1 wt%) composite nanofiber membrane displayed an optimal reflection loss of −53. BNT/PTFE composites with high dielectric constant and low loss properties were prepared via powder processing technique. My Research and Language Selection Sign into My Research Create My Research Account English; Help and support. In addition, the PTFE/F-GF composite shows improved density (2. The 30 vol% BN-PDA-KH560/NBR composite not only exhibited relatively high dielectric constant (9 at 100 Hz) but also remained low dielectric loss tangent (0. Materials with a low loss tangent and low relative permittivity are essential for the next. e. It doesn't mean that you don't have this property in any other types of circuit. 0005 0. Measured tanδ for partially cross-linked SU-8 was 0. 6 mm thick fabric polytetrafluoroethylene (PTFE) substrate with a dielectric constant of 2. 5-10. 8" L=8. 8 × 10 −4, at 15 K. 2021, 11, 6813 7 of 9. 9. PTFE loss tangent AFM study: (a). 0041. 0, 4. CLTE-XT™ Laminates. 1 at 10 GHz (Fig. 1 rad/s to 100 rad/s in Fig. 8°,. 009: BETTER Dielectric Constant 3. 2. Wang) The discussion in this section has assumed that [Math Processing Error] ϵ c is complex-valued solely due to ohmic loss. With its low Dk loss, RT/duroid 5870 laminates are well suited for high frequency/broadband applications where dispersion and losses need to be minimized. Dynamic mechanical analysis (DMA, TA Q850) was performed in tensile mode. 35 40 0. 2 Radome Design Elements. Hence, in this paper, PTFE and spherical CNT were chosen as polymer matrix and ceramic filler, respectively. 2E-4 @100 MHz. 1. The main attributes of MEGTRON 6/6G are: low dielectric constant and dielectric dissipation factors, low transmission loss and high heat resistance; Td = 410°C (770°F). , their dielectric constants are not dependent of the frequency as electronic polarization is instantaneous regardless of frequency. 305), decreased dielectric loss (9. In the case of cement–matrix composites, both loss tangent and storage modulus are greatly enhanced by the addition of silica fume. 3 Properties under impact stress 40 3. ER=4. 058 at 100 GHz and 2 THz, respectively. Dielectric constant: Although this is sometimes misunderstood, and everyone tends to just go for low-Dk laminates, but high-Dk. 0020 5 15 25 35 45 55 65 Loss Tangent Frequency (GHz) PTFE Teflon® Type A L=4. In loss tangent AFM, the AFM cantilever is excited, similar to amplitude modulation AFM (also known as tapping mode); however, the observable aspects are used to extract dissipative and conservative energies per cycle of oscillation. I am. RO3000® Series. /. 1 and a loss tangent<0. 1. The dielectric constant and dielectric loss of the PTFE substrate was obtained by testing at 1 GHz and 10 GHz, respectively. At 80% relative air humidity, chemically modified jute fabrics have 38–179% and 1. Utilizing extended technology for higher performance, CLTE-XT laminates are ceramic/PTFE microwave composites that provide. TC600™ Laminates are composites of PTFE, thermally conductive ceramic fillers and woven glass reinforcement. ThunderClad 3+’s electrical performance is competitive with PTFE-based, hydrocarbon-based very low loss materials, but capable for high layer count circuit board design with excellent thermal reliability. tetrafluroethylene (PTFE) is selected as the polymer matrix owing to its extremely low loss tangent, higher solvent re-sistance, low moisture absorption, etc. Tefzel® can be extruded or injection molded easily, using conventional techniques, and thus presents no unusual operator training. 1, its loss tangent is 0. Dk value: ~3. Using precision control of the fiberglass/PTFE ratio, CuClad laminates offer a range of choices from the lowest dielectric constant and loss tangent to a more highly reinforced laminate with better dimensional stability. 40 Glass Transition (Tg) >280 170 - ˚C TMA A - IPC-TM-650 2. 1 and loss tangent as low as 0. Note that loss tangent is zero for a lossless ((sigmaequiv 0)) material, and increases with increasing loss. 1. Figure 7d shows the loss tangent (tan. Dissipation Factor The ratio of loss current to charging current. 0005 0. SFR reduces transmission loss by about 20% at 60 GHz, compared with LCP and PTFE. 5 S/m. However, the changes of the electrical property (including dielectric constant and loss tangent) are complex and hard to be obtained and analyzed. However, the application of PTFE was hindered by its high CTE (∼400 ppm/ o C) due to its room temperature phase transformation. 5 ¥ 10-3 at 60 GHz which exhibits significant impact on total loss in mm-Wave device but the processing for PTFE is also known to be difficult. The loss tangent for ptfe is about 0. At 80% relative air humidity, chemically modified jute fabrics have 38–179% and 1. order to design a product with the advantages of low loss tangent and suitability for sequential lamination. The low loss tangent is a consequence of the symmetrical conformation of the polymer backbone, which effectively neutralizes the dipole forces of the C–F bonds yielding a net zero dipole. PTFE laminates are a specialty material despite. Despite relatively high signal loss and low thermal rating, FR1 PCB offered a low-cost material choice. Center Conductor: 0. Download scientific diagram | Dielectric constant and loss tangent for (a) PTFE, (b) polystyrene, and (c) nylon samples in the Ka-band by using NRW method and optimization solution. 3 TiO 3 (CNT) ceramic possesses both high dielectric constant ( εr ~100) and low loss tangent (5. Appl. Loss tangent presuming only ohmic (conduction) loss is given by Equation 3.