Multilayer PCB's represent one of the most complicated products in the PCB industry. A breakdown of a multilayer PCB shows that it consists of three basic elements: thin rigid laminates, prepreg sheet for bonding the laminates and copper foils.
Purpose of Multilayer PCBs
1) To accommodate a larger number of interconnections that steadily increasing use of high pin-count integrated circuits(IC).
2) To establish an electrical performance of the multilayer PCB, such as voltage and ground planes, EMC-shielding and circuit speed etc.
The purpose of stackup is to interleave the thin laminates and the prepreg sheets in correct sequence and ensure correct layer-to-layer registration. The stackup of multilayer boards can be done in many different ways.
The process of multilayer PCB
1) In general, a multilayer board consists of a number of very thin print-and-etch inner layers, but drilling of holes has not been carried out. Outer layers of the multilayer board remain unetched.
2) Layers from top to bottom are bonded together in close registration by means of thin plies of prepreg. The bonding is performed under close temperature and pressure control in a lamination press.
3) After lamination, they are the processed in very much the same way as an ordinary double-sided PTH boards, i.e. holes are drilled, cleaned and plated. Outer layers are etched to develop the circuit pattern. Solder masks are applied and solder coating (HAS, ENIG etc) is performed.
Thin laminate (base masterial FR-4)
|SHENGYI||S1141||0.05-3.2 mm||17-105 μm||≥130||≤5.4|
|SHENGYI||S1170||0.05-3.2 mm||17-105 μm||≥170||≤5.4|
|ITEQ||IT-140||0.05-1.5 mm||17-175 μm||>135||＜5.4|
|ITEQ||IT-180||0.05-1.5 mm||17-175 μm||>170||＜5.4|
|ITEQ||IT-180A||0.05-1.5 mm||17-175 μm||>170||＜5.4|
Comparison of different Prepreg.
|Type of Prepreg||Finished Thickness||Resin Content|
Payment & Shipping Terms:
|Glass Epoxy:||FR-4 Tg150℃, Er<5.4.IT-158, ITEQ Supplied||Board Thick:||1.6 Mm ±0.16|
|Outer Copper Thick:||1 Oz||Inner Copper Thick:||1 Oz|
|Surface Finish:||Immersion Gold (22.1% ) 0.05 µm Over 3 µm Nickel||Solder Mask Color:||Green|
|Colour Of Component Legend:||White||TEST:||100% Electrical Test Prior Shipment|
1.1 General description
This is a type of multilayer PCB built on FR-4 substrate with Tg 150°C for the application
of X-ray equipment. It's 2.0 mm thick with white silkscreen(Taiyo) on green solder mask
(Taiyo) and immersion gold on pads. The base material is from ITEQ supplying 2 up
PCBs per panel. They're fabricated per IPC 6012 Class 2 using supplied Gerber data.
Each 20 panels are packed for shipment.
1.2 Features and benifits
A. Very Low Moisure Absorption and better CAF resistance
B. Excellent surface planarity for CSP mounted components to reduce failure rate during
assembly and soldering.
C. High assembly density and small size
D. Comprehensive equipment management and maintenance and process control
E. ISO9001, ISO14001, UL certified manufacturing factory.
F. Eligible products rate of first production: >95%
G. No MOQ, low cost for prototypes and small runs quantity.
Dsl Modem, Bluetooth For PC, Vehicle Tracker, GPS Vehicle Tracking, Wi Fi Antenna,
Electronic Counter, USB Wireless Router, DCDC Converter, Multicoupler Antenna,
Space probe equipment
1.4 Parameter and data sheet
|PCB SIZE||221 x 281mm=2PCS|
|BOARD TYPE||Multilayer PCB|
|Number of Layers||4 layers|
|Surface Mount Components||YES|
|Through Hole Components||YES|
|LAYER STACKUP||copper ------- 18um(0.5oz)+plate TOP layer|
|Prepreg 7628(41%) 0.185 mm|
|copper ------- 35um(1oz) MidLayer 1|
|FR-4 1.48 mm|
|copper ------- 35um(1oz) MidLayer 2|
|Prepreg 7628(41%) 0.185 mm|
|copper ------- 18um(0.5oz)+plate BOT layer|
|Minimum Trace and Space:||5.7 mil/ 5 mil|
|Minimum / Maximum Holes:||0.5 mm /3.2 mm|
|Number of Different Holes:||8|
|Number of Drill Holes:||315|
|Number of Milled Slots:||8|
|Number of Internal Cutouts:||16|
|Number of Gold finger:||0|
|Glass Epoxy:||FR-4 Tg150℃, er<5.4.IT-158, ITEQ Supplied|
|Final foil external:||1 oz|
|Final foil internal:||1 oz|
|Final height of PCB:||2.0 mm ±0.2|
|PLATING AND COATING|
|Surface Finish||Immersion gold (22.1% ) 0.05 µm over 3 µm nickel|
|Solder Mask Apply To:||TOP and Bottom, 12micron Minimum|
|Solder Mask Color:||Green, PSR-2000GT600D, Taiyo Supplied.|
|Solder Mask Type:||LPSM|
|CONTOUR/CUTTING||Routing, stamp holes.|
|Side of Component Legend||TOP and Bottom.|
|Colour of Component Legend||White, IJR-4000 MW300, Taiyo Supplied.|
|Manufacturer Name or Logo:||Marked on the board in a conductor and leged FREE AREA|
|VIA||plated through hole(PTH), minimum size 0.5mm.|
|FLAMIBILITY RATING||UL 94-V0 Approval MIN.|
|TEST||100% Electrical Test prior shipment|
|TYPE OF ARTWORK TO BE SUPPLIED||email file, Gerber RS-274-X, PCBDOC etc|
|SERVICE AREA||Worldwide, Globally.|