SMT, PCB Electronics Industry News

Raw Material Choices for PCBs

Oct 18, 2018

This article provides recommendations for choosing materials to manufacture multilayer PCBs that achieve two critical requirements: limit manufacturing problems (e.g., bowing or twisting, as well as mis-registering; and meeting performance standards. A successful PCB production begins with proper material selection. For a low number of board layers, your PCB manufacturers default materials are usually your best choice as they are reliable and cost effective. However, when designs have special requirements or incorporate a high number of layers, then it is worth a designer’s effort to become more familiar with the available material options, in order to make the best decisions for their product. 

The most important material for PCB manufacturing is raw laminate. It also represents the largest cost of all other materials needed to produce a multilayer PCB. Raw laminate has a critical impact for the prices and the delivery time of PCBs. Due to the amount of material needed for PCB fabrication, it is essential to optimize the size of your designs; even a small difference in size can result in a significant difference in cost. Different materials incur different costs and possess different characteristics, but higher quality laminates are typically also more expensive. The following are some of the main characteristics to take note of when comparing properties of different laminates: 

Tg = Glass Transition Temperature – Temperature at which a critical change of physical properties will occur. In the case of laminates, it transitions from a hard, glassy material into a soft, rubbery material 

Td = Decomposition Temperature - Temperature at which the laminate chemically decomposes 

Dk = Dielectric Constant (also referred to as ?r in electromagnetics) – Indicates the relative permittivity of an insulator material, which refers to its ability to store electrical energy in an electric field. For insulating purposes, a material with lower dielectric constant is better and in RF applications a higher dielectric constant may be desirable 

Df = Dissipation Factor – Indicates the efficiency of an insulating material by showing the rate of energy loss for a certain mode of oscillation, such as mechanical, electrical, or electromechanical oscillation 

Our fabrication facilities are located in China, so it is advisable to choose high-quality local laminates in order to minimize shipping cost and lead time. The Shengyi S1000-H (Tg 150) laminate is generally our default choice for a high-performance, mid-Tg laminate. Shengyi S1000-H is comparable to Isola FR406 (Tg 150), a standard North American laminate option. As outlined in Table 2 below, FR406 does slightly outmatch Shengyi S1000H in terms of Dielectric Constant and Dissipation Factor, but some clients may be willing to compromise on these factors for a lower cost and/or a faster lead time. 

Table 1: Comparison of PCB Materials 

Shengyi S1141 (TG 130) is a good alternative to lower the cost of your project, at the sacrifice of some quality. In cases where higher quality is needed, we recommend Shengyi S1000-2M (TG 170) which is the closest in quality to Isola FR406 (Tg 170). Where quality is the highest priority, we would recommend utilizing ITEQ IT180A (TG 180) which is also RoHS compliant. ITEQ IT180A (TG 180) is comparable in quality and to Isola 370HR (TG 180). We at Bittele would suggest using Shengyi S1000H (Tg 130) for typical projects. We would recommend using one of the higher quality laminate materials if any of these three conditions occur: if the PCB Design has 8 or more layers, if Copper Board is heavy with a copper weight heavier than 3oz, or if PCB Board is thin with a board thickness of less than 0.5mm. 

The next element to consider is the dielectric thickness, which must be specified for impedance requirements. Multilayer materials range from 0.125mm to 1mm in thickness. Thin laminates (i.e. 0.1mm or less) are necessary for some low-power applications as well as the continued densification of multilayer circuit PCBs. 

Table 2 lists the core material thickness with copper weight for normal FR4 Material

  • 1/1 = 1 oz. copper per square foot on BOTH sides of the sheet
  • 1/0 = 1 oz. copper per square foot, coated on only 1 ONE side of the sheet
  • H/H = 0.5 oz. copper per square foot, coated on BOTH sides of the sheet
  • 0/0 = UNCLAD (NO Copper).


Table 2: Core material thicknesses at available copper weights 

Thickness including copper (mm.)Copper Weight (oz.)

0.145 mm.H/H oz.

0.17 mm.1/1 oz.

0.185 mm.H/H oz.

0.2 mm.1/1 oz. or H/H oz.

0.25 mm.1/1 oz. or H/H oz.

0.3 mm.1/1 oz. or H/H oz.

0.4 mm.1/1 oz. or H/H oz.

0.5 mm.1/1 oz. or H/H oz.

0.6 mm.1/1 oz. or H/H oz.

0.7 mm.1/1 oz. or H/H oz.

0.8 mm.1/1 oz. or H/H oz.

0.9 mm.1/1 oz. or H/H oz.

1.0 mm.1/1 oz. or H/H oz.

1.1 mm.1/1 oz. or H/H oz.

1.2 mm.1/1 oz. or H/H oz.

1.5 mm.1/1 oz. or H/H oz.

1.6 mm.1/1 oz. or H/H oz.

2.2 mm.1/1 oz.

2.4 mm.1/1 oz.

2.5 mm.1/1 oz.

3.0 mm.1/1 oz.


Prepreg is a bonding material used in the fabrication of multi-layer PCB boards which, after curing has the same properties as the core /base layer materials. Prepregs have various glass styles 106, 1080, 3313, 2116 and 7628 used by board fabricators. Board fabricators use a variety of prepreg glass styles. These styles include 106, 1080, 3313, 2116 and 7628. Limitations may apply to the number and types of prepreg, so it is best to contact a Bittele representative for further details. 

Table 3: Prepeg material choices 

Prepreg /Glass StylesPressed Thickness (mm)Prepreg Resin content

1060.05 mm.Approx. 73%

10800.075 mm.Approx. 65%

33130.09 mm.Approx. 57%

21160.115 mm.Approx. 55%

76280.185 mm.Approx. 46%

7628H0.195 mm.Approx. 51%



Lastly, the thickness of copper layers should be specified. This specification is usually decided based on the amount of current that is expected to pass through the traces of a board. Use our Trace Width Calculator to determine standard trace widths for a given copper thickness. Thicker traces can safely handle more current than thinner traces of the same width. You may also wish to specify thicker copper layers for a more robust board if you expect the board to be operating in harsh conditions. 

Copper clad FR-4 laminate materials are measured using ounce(oz.) weight per square foot. The following are available sizes and their equivalent layer thickness

  • 0.25 oz. = 0.00035” (8.75?m)
  • 0.5 oz. = 0.0007” (17.5 ?m)
  • 0.75 oz. =0.00105” (26.25?m)
  • 1.0 oz. = 0.0014” (35 ?m)
  • 2.0 oz. = 0.0028” (70 ?m)
  • 3.0 oz. = 0.0042” (105 ?m)
  • 4.0 oz. or more = 0.0056” (140 ?m) or more

Bittele Electronics is capable of fabricating multi- layer PCB boards with a maximum copper weight of 10 oz. Copper weight of 4 oz. or higher will require an additional estimate, and may also affect lead times.

http://www.flason-smt.com/new/Raw-Material-Choices-for-PCBs.html

When SMT matter to your business, partner with Flason. Where innovation takes form.
reflow oven lead free reflow oven LED strip reflow oven dual rail reflow oven custom reflow oven China reflow ovenSMT Peripheral Equipment SMT reflow oven 
wave soldering machine pick and place machine lead free wave soldering machine custom wave soldering machinecustom pick and place machine SMT Assembly line
SMT Reflow Oven Manufacturer Wave Soldering Mahchine Manufacturer Pick and Place Machine Manufacturer Reflow Oven Manufacturer SMT Spare Parts LED Pick and Place Machine
Andrey: sales@flason-smt.com Wechat whatsapp:+86 13691605420 

Keywords: Reflow Oven SMT Reflow Oven Wave Soldering Machine SMT Stencil Printer Pick and Place Machine SMT Inspection machine SMT Assembly Line SMT Peripheral Equipment SMT Spare Parts reflow oven lead free reflow oven LED strip reflow oven dual rail reflow oven Custom reflow oven China reflow oven SMT Peripheral Equipment SMT reflow oven wave soldering machine pick and place machine lead free wave soldering machine custom wave soldering machine custom pick and place machine SMT Assembly line SMT Reflow Oven Manufacturer Wave Soldering Mahchine Manufacturer Pick and Place Machine Manufacturer Reflow Oven Manufacturer SMT Spare Parts LED Pick and Place Machine

For More information,visit US: Reflow Oven Manufacturer or SMT Reflow Oven Wave Soldering Machine SMT Stencil Printer Pick and Place Machine SMT Inspection machine SMT Assembly Line SMT Peripheral Equipment SMT Spare Parts SMT Feeder SMT Nozzle Feeder storage cart USB Flash Drive Manufacturer wave soldering machine manufacturer Email us: sales@flason-smt.com

Dec 08, 2018 -

Lead-Free (Pb-Free) Solder and Composition

Dec 08, 2018 -

All about Semiconductor

Dec 08, 2018 -

Top 10 Consumer Electronics Companies in the World

Dec 08, 2018 -

How Electronic / Electrical Circuit Works

Dec 08, 2018 -

Ball Grid Array (BGA) Package

Dec 08, 2018 -

SMT Dictionary – Surface Mount Technology Acronym and Abbreviation

Dec 08, 2018 -

Printed Circuit Board (PCB) for Surface Mount Technology (SMT)

Dec 08, 2018 -

Basic Soldering Guide – How to Solder Electronic Components

Dec 08, 2018 -

RoHS Guide in Electronics: RoHS, WEEE and Lead-Free FAQ

Dec 08, 2018 -

Electronic Components, Parts and Their Function

133 more news from Flason Electronic Co.,limited »

Oct 19, 2021 -

XJTAG Ultra-Fast Flash Programmer

Oct 18, 2021 -

Summit Interconnect Earns IPC-1791, Qualified Manufacturers Listing (QML) as Trusted Electronics Fabricator

Oct 18, 2021 -

Insituware Application Engineer Presenting at SMTAI

Oct 18, 2021 -

Join KYZEN in Person at SMTA International to Find the Right Solution for Any Process

Oct 18, 2021 -

CiRCLE Engineers Purchases Hentec/RPS 1325 Odyssey Lead Tinning System for Israel Facility

Oct 17, 2021 -

Transition Automation to Exhibit at SMTA Austin Expo and Tech Forum on October 19th

Oct 17, 2021 -

Southwest Systems Technology to Demo Thermaltronics Robotic Soldering Systems at the SMTA Austin Expo

Oct 17, 2021 -

XDry to Discuss Humidity Controlled Storage Cabinets at SMTA Austin Expo

Oct 17, 2021 -

PCBASupplies to Represent Its Full Line of PCB Assembly Products at SMTA Austin

Oct 17, 2021 -

STI Recognizes Pam Whalen's 15-Year Anniversary

See electronics manufacturing industry news »

Raw Material Choices for PCBs news release has been viewed 477 times

Reflow Oven

Voidless Reflow Soldering