Circuit Board Laminates as a part of High Frequency PCB
Transcription
Circuit Board Laminates as a part of High Frequency PCB
Circuit Board Laminates as a part of High Frequency PCB Aspocomp – Piirilevytekniikkaa 2015 Oulu on 10.2.2015 Mika Sillgren Content • Panasonic Electronic Materials Business Division brief • High speed laminate trends • Dielectric material production process • Key Characteristics of dielectric laminates for high speed circuit boards – Resin system • • – Copper foil • • – Dk/Dielectric constant Df/Dissipation factor Roughness Inner layer treatment Glass cloth • • Glass cloth style (E-glass vs. NE-glass) Spreading of Glass cloth • Panasonic circuit board material offering for high speed applications • Summary and Key takeaways Panasonic 2 Trends Process Characteristics – Resin – Copper foil – Glass cloth © Panasonic Corporation Electronic Materials Business Division Materials Summary Panasonic Corporation - Four Company System Electronic Materials Business Division 3 © Panasonic Corporation Electronic Materials Business Division Product Development from viewpoint of customer Requirements ・Switches ・Base Stations ・etc. ・Servers ・Routers Networking Equipment IC Substrates IC Substrate Materials series Products Low Dk/Df and High Tg Circuit Board Materials series ・ ・ ・ ・ ・ LED, Automotive, Power Device High thermal dissipation Materials ・BOCs (Black type) ・PC-BGAs Evaluation and Analysis Acquired Technology Technology ・ ・ ・ ・Halogen-free FR-4 ・Halogen-free CEM-3 ・Halogen-free FR-1 Automotive series ・ ・ ・ PreMulti Material Design Technology Halogen free ・etc. High Reliability Circuit Board Materials Process Technology series ・LED back light ・ECUs, Headlamp ・LED lightings ・etc. ・CSP Cards (Mass laminations) ・Automotive ・etc. Flexible Circuit Board Materials series Advanced Films ・TVs ・Note PCs ・DVCs ・DVD Players ・Printers ・DVD-ROM drives ・etc. ・Laundry machines Home Appliances PC-related Devices 4 © Panasonic Corporation Electronic Materials Business Division series ・Tablet PCs ・Note PCs ・Digital Audio Players ・etc. ・Smart phones ・DSCs Mobile Products Global Production System We have production bases in China, Asia, Europe and Japan to effectively support customer’s global production. Multi-layer Materials Foundation 2000 R&M PIDM Europe R&M Foundation 1995 Multi-layer Materials CEM-3 R&D Circuit Board Multi-layer Materials Foundation 1999 PIDM Guangzhou PIDM Suzhou R&M Molding Compounds Encapsulation materials Research & Marketing Group PIDM Shanghai Europe N.America China Japan Asia Foundation 1970 Multi-layer Materials Encapsulation materials PreMulti Foundation 1961 Molding Compounds Molding product Advanced Film Flexible CCL PIDM Koriyama PIDM Singapore Foundation 1996 Paper Phenolic CCL Molding Compounds Encapsulation materials Foundation 2001 Multi-layer Materials Foundation 1986 CEM-3 Flexible CCL Encapsulation materials PMF Ayutthaya 5 Foundation 1987 Multi-layer Materials PIDM Yokkaichi PIDM Taiwan © Panasonic Corporation Electronic Materials Business Division Electronic Materials Business Unit PIDM Koriyama West Factory PIDM Yokkaichi South Factory High speed laminate trends – Examples of Applications Navigation systems 1.2–1.6 GHz Bluetooth 2.4 GHz RFID W-LAN 850–950 MHz 2.4 – 5.8 GHz Mobile phones 800 Mhz – 3.8 GHz WIGIG 60 GHz Networking systems 3 – 6 GHz Optical systems >10 GHz Router 5-14GHz Server 4-12 GHz Car radar systems FM Radio 24 – 79 GHz 88 - 108 MHz TV broadcasting D-TV satellites VHF: 50 - 230MHz UHF: 470 - 890MHz Frequency 100MHz 1GHz 10 Wave length [m] UHF 6 11 – 15 Ghz 1m 10GHz 1-1 VHF © Panasonic Corporation Electronic Materials Business Division 10cm 100GHz 1-2 SHF 1cm 1-3 EHF 1mm High speed laminate trends – ICT segment Source: LinLin ECWC13 7 © Panasonic Corporation Electronic Materials Business Division High speed laminate trends – ICT segment Source: LinLin ECWC13 8 © Panasonic Corporation Electronic Materials Business Division Dielectric material production process – raw materials Copper foil Copper Clad Laminate (Fully cured) Resin Prepreg (Semi-cured) Glass cloth Raw materials 9 Products © Panasonic Corporation Electronic Materials Business Division Customer products Laminate and Prepreg Production process Acceptance of raw materials 1 Varnish Blending 2 Varnish Impregnation Produces the varnish by blending epoxy resin, solvent, catalyst and hardening agent. 3 4 Drying Cutting Drying of varnish-impregnated glass cloth, and detection of foreign materials by appearance inspect. Prepregs are ready. Solvent Copper foil Catalyst Hardening agent Epoxy resin Glass cloth Epoxy resin Yarn 5 6 7 8 9 Build-up Build-up Press Break-down Inspection Packing Cover prepregs by copper foil and stainless plates. Lamination process for CCL. Lamination of copper foil to prepregs by pressure and heat in vacuum press. Remove the stainless plates from copper clad laminate. Stainless plate Copper foil Prepreg Copper Clad Laminate 10 © Panasonic Corporation Electronic Materials Business Division Inspection of CCL appearance and packing. Electrical characteristics of resin and glass (Dk and Df) ※@1MHz 10-1 Dissipation factor Thermosetting Resin Epoxy 10-2 Polyimide Thermoplastics Resin PPO 10-3 PP PE PS PTFE 10-4 Polymethylpentene 10-5 1 2 3 4 5 Dielectric constant Properties of glass 11 Final properties of laminates and prepregs are combination of properties of resin- and glass cloth used. © Panasonic Corporation Electronic Materials Business Division Electrical characteristics of resin (impact of resin + glass to Dk) 12 Dk level of laminate is depending on resin content (ratio of glass cloth and resin) used, and is varying even for same laminate product. © Panasonic Corporation Electronic Materials Business Division Electrical characteristics of resin – Why Low Dk/Df for HS boards? Formula for impedance Zo = 5.98h 60 ln √εr π(0.8W+t) 100um 13 150 140 130 120 110 100 90 80 70 60 50 Cu thickness :t=35μm Impedance:50 Ω 2 3 Dk 4 5 Cu thickness :t=35μm Impedance:50 Ω 0.45 Dielectric thickness [mm] Circuit width [um] 0.25 mmt 0.4 0.35 0.3 0.25 0.2 0.15 0.1 2 3 4 5 Dk Lower Dk ⇒ Wider circuit patterns and thinner dielectric layers Easier manufacturability, more robust design (tolerances), product miniaturization (thickness), etc. © Panasonic Corporation Electronic Materials Business Division Electrical characteristics of resin – Why Low Dk/Df for HS boards? 14 Signal transmission loss is sum of conductor loss and dielectric loss. Dk and Df are both impacting on transmission loss. © Panasonic Corporation Electronic Materials Business Division Electrical characteristics of resin – Panasonic HS product offering 15 © Panasonic Corporation Electronic Materials Business Division Electrical characteristics of resin - Transmission Loss comparison PCB construction Transmission Loss (dB/m) 0 -5 16 35um -10 -15 [RT] -20 [RT] -25 [RT] -30 R-1566 [RT] -35 R-1755V [RT] -40 Copper type: RT 0 1 2 3 4 Frequency (GHz) 5 6 Lower Dk/Df of materials has direct impact on signal transmission loss. © Panasonic Corporation Electronic Materials Business Division 250um Key Characteristics – Why copper foil roughness is important? • “Skin effect is the tendency of an alternating electric current (AC) to become distributed within a conductor such that the current density is largest near the surface of the conductor, and decreases with greater depths in the conductor. The electric current flows mainly at the "skin" of the conductor, between the outer surface and a level called the skin depth. The skin effect causes the effective resistance of the conductor to increase at higher frequencies where the skin depth is smaller, thus reducing the effective cross-section of the conductor.” Source: Wikipedia (http://en.wikipedia.org/wiki/Skin_effect) Frequency Skin effect depth 10 kHz 660 μm 100 kHz 210 μm 1 MHz 65 μm 10 MHz 21 μm 100 MHz 6.6 μm 1 GHz 2.1 μm 10 GHz 0.7 μm Higher the frequency - more significant the impact of skin effect to transmission loss. 17 © Panasonic Corporation Electronic Materials Business Division Higher Resistance Key Characteristics – Why copper foil roughness is important? Signal path Higher Resistance Signal path Low frequency signals High frequency signals Copper profile is one of the main contributors for transmission loss for high frequency signals. 18 © Panasonic Corporation Electronic Materials Business Division Key Characteristics – Copper profile classification by IPC Copper profile classification based on IPC-4562: >10.2 μm Standard (S) Mat side Conventional (Low Profile) 5.2 – 10.2 μm Low profile (L) <= 5.1 μm Rz=6~8μm H-VLP Very Low profile (V) No Treatment or Roughness (X) RT (Reverse Treated) Rz=3~4μm Rz=1~2μm Typically high frequency laminates use either Low profile or Very Low Profile copper profile types. Low/No Peel strength limiting X-style copper usage. 19 © Panasonic Corporation Electronic Materials Business Division Key Characteristics – Transmission loss vs. Cu foil type Cu Thickness:35μm Cu Type :H-VLP, RT, Conventional Inner treatment Type: None ・Core : 6MIL (0.13t) (#2116x 1ply), Mat side ・Prepreg: #1080 RC64% *2ply Line length : 200, 100mm Impedance : 50 Ω H-VLP Rz=1~2μm Transmission loss (dB/100mm) 0 RT -2 H-VLP Rz=3~4μm -4 [H-VLP] RT Conventional (Low Profile) [RT] -6 Conventional Rz=6~8μm -8 0 5 10 Frequency (GHz) 15 20 Copper profile impact on transmission loss is getting bigger with higher frequencies. Usage of conventional copper profile increase transmission loss significantly. 20 © Panasonic Corporation Electronic Materials Business Division Key Characteristics – E glass vs. NE glass Dk & Df (MEG7) NE-glass (Low Dk glass) reduces effective Dk of the material by 0.2 – 0.3 vs. E-glass. Df of NE-glass version is slightly better than E-glass version. 21 © Panasonic Corporation Electronic Materials Business Division Key Characteristics – E glass vs. NE glass transmission loss (MEG7) The difference of transmission loss between E-glass and NE-glass version of MEGTRON7 material is ~4dB/m at 20GHz. The impact is almost on the same as the difference between H-VLP and RT copper foil. 22 © Panasonic Corporation Electronic Materials Business Division Key Characteristics – Spreading of glass cloth Differences in Propagation delay & loss are minimized with Spread Glass Conventional glass cloth 23 © Panasonic Corporation Electronic Materials Business Division Spreaded glass cloth Key Characteristics – Dk difference between glass and resin Glass DK = 6.4 (IPC-4412) 3.1.6.1 Dielectric Constant for Base E-Glass The DK of base E-glass to be used for printed board applications is 6.4 @ 1 GHZ (as measured by IPC-TM-650, Method 2.5.5.9) Resin/Filler DK = 2.5 - 4.5 RC VS DK@1GHZ STD FR-4 FILLED FR-4 FILLED LOW LOSS A FILLED LOW LOSS B 5.5 FILLED LOW LOSS C FILLED LOW LOSS D FILLED LOW LOSS E DK @ 1GHz 5 4.5 4 3.5 3 RC% 24 © Panasonic Corporation Electronic Materials Business Division 85 75 65 55 45 35 25 15 2.5 Key Characteristics – Dk difference between glass and resin 25 © Panasonic Corporation Electronic Materials Business Division Key Characteristics – Conventional Glass vs Spread Glass Delay Time vs Frequency Delay Tim e vs Frequency(#1078) Delay Time vs Frequency(#1 0 8 0 ) 1.28E-09 1.28E-09 1.27E-09 Delay Tim e [sec] 1.27E-09 Delay Time [sec] 1.26E-09 Max 1.25E-09 1.24E-09 Min 1.23E-09 1.26E-09 1.25E-09 Max 1.24E-09 Min 1.23E-09 1.22E-09 1.22E-09 0 1 2 3 4 5 Frequency [GHz ] 26 1078 (spread weave) 1080 (conventional weave) © Panasonic Corporation Electronic Materials Business Division 6 0 1 2 3 4 Frequency [GHz ] 5 6 Electrical characteristic of resin – Panasonic HS product offering Dk: 3.7 / 3.4(N) Df: 0.002 / 1GHz, 0.0015 / 1GHz(N) Dk: 4.1 Df: 0.01 / 1GHz Dk: 4.4 Df: 0.016 / 1GHz Dk: 4.6 Df: 0.01 / 1GHz 27 © Panasonic Corporation Electronic Materials Business Division Dk: 3.8 Df: 0.005 / 1GHz Dk: 3.6 / 3.4(N) Df: 0.0015/1GHz 0.001 / 1GHz (N) Summary and Key takeaways • Higher the frequency requirements for your application/PCB more you need to understand laminates used in it. • Resin system, glass cloth and copper have all significant impact on transmission loss in high frequency PCB‘s – you can lose good performance by specifying wrong property for other parameter. • Low loss resin system, smooth copper profile and use of spreaded glass cloth style with Low Dk/Df properties help you tackle challenges of high frequencies. • Panasonic comprehensive circuit board material offering can meet your varying application requirements with good quality and high reliability today and in future! 28 © Panasonic Corporation Electronic Materials Business Division 29 © Panasonic Corporation Electronic Materials Business Division