technological trends in the field of circuit board design and manufacturing

Technological Trends in the Field of

Circuit Board Design & Manufacturing

Published by:

|www.toradex.com Toradex® is a registered trademark of Montadex GmbH Aug’15 2

CHAIRMAN

Introduction

Circuit boards are found in all electronic products. The advancement in

semiconductor technology is driving the giant electronics industry. PCB industry

has been quickly responding to the rapidly evolving global electronics market.

Today, circuit board designers should have a thorough knowledge of both

electrical engineering and manufacturing technology. Collaborating with EMS

vendors during early stages will helps the designers to reduce design risks and

find cost effective solutions.

This article will provide a brief overview of the technological trends prevailing

in the field of printed circuit technology and serve as a walkthrough to the

lesser known technologies in the printed circuit market.


CHAIRMAN

Market trends:

43%

0%1%

11%

16%

14%

6%

4%5%

0% 0%

Global PCB Market: Based on Geography

China

Hong Kong

India

Japan

South Korea

Taiwan

Other Asia

West Europe

North America

Central and South America

Israel and North Africa


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11%

37%

15%

15%

18%

3%

1%

Global PCB Market: Based on Technology

Rigid 1-2 Sided

Standards Multilayer

HDI / Microvia / Buildup

IC Substrate

Flexible Circuits

Rigid Flex

Others


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Asian countries continue to fulfil the majority of the global PCB demand.

China, South Korea, and Taiwan continue to fulfill the huge demand created

by markets for smartphone, tablet computers, display monitors, and TV.

Export to western countries also accounts for a major chunk of the global PCB

demand because of highly competitive pricing offered by the Asian PCB

manufacturing industry.

The European PCB industry focuses on low volume and high-end markets like

instrumentation and control, automotive, medical, military, and aerospace.

Production in North America is dominated by the USA, largely occupied by

military, aerospace and defense sectors.

From technological point of view, a standard multilayer PCB still commands a

large share of the market. With global trend of miniaturization of electronic

products, HDI and Rigid-Flex technology will continue to grow in future.


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Industry Challenges

With advancement in ICs package technology, mobile revolution, and IOT

kicking in, PCB geometries will continue to shrink. Designing ultra-thin printed

circuit boards which meets the required signal integrity and EMC specifications

at low cost will be challenging.

Technology Trends

Printed circuit boards can be broadly classified into:

1) Conventional PCB (Single-sided, Double-sided and Multilayer PCB)

2) Flexible and Rigid-Flex PCB

3) High Density Interconnect (HDI)


CHAIRMAN

Example HDI board using “2-N-2” HDI Buildup (N = number of standard layers)


CHAIRMAN

HDI technology has been used in manufacturing products like wearables,

smartphones, and tablet devices.

One of the major challenges faced by the PCB industry is increasing the layer

count and reducing the thickness of the circuit boards without compromising the

structural rigidity and electrical performance of a PCB. The average thickness of

a PCB is around 0.5 mm to 0.7 mm and is expected to be less than 0.4 mm in

next few years.

Compared to the 0.7mm pitch BGA package used in smartphones a few years

ago, latest smartphones uses 0.4 mm pitch BGA package which offers a higher

pin count in smaller PCB real estate. The IC industry has already been working on

0.3mm pitch BGA technology for next generation microprocessors and FPGAs.


CHAIRMAN

IC substrate manufacturers have developed “mSAP” (Modified Semi Additive

Process) process which is capable of creating fine lines with better conductor

geometry. The HDI PCB industry is adapting to the mSAP process to tackle the

upcoming challenges. While 90% of production uses the Contact Imaging Process

today. Laser direct imaging (LDI) looks like a promising technology for the future.

With 0.3 mm pitch BGA, microvia pad/hole size is expected to be in the order of

150um/75um, respectively. While, PCB industry will continue to use CO2 laser

for drilling microvia in near future. New lasers with picosecond pulse are coming

to the market which offers finer holes and drastically lower thermal damage.

ALV (Any Layer Via) HDI technology is currently expensive and requires a state-

of-the-art facility. In coming years, 10 to 12 layer microvia layer buildup will be

common in next generation handheld and wearable devices.


CHAIRMAN

Rigid flex technology has enabled designers to replace the PCB connectors and

wire with single PCB, offering improved performance, reliability, and reduced

weight. Rigid Flex HDI offers designer to build next generation electronics

device which can follow the form. With wearable technology gaining

popularity, the use of Flex and Rigid Flex HDI technology will continue to grow.

Embedded Components

Since several years, various 3D-Integreation approaches have been explored to

keep the pace with the continuing trend towards electronics miniaturization

and densification. PCB embedding of passive and active devices has emerged

as a highly potential and scalable technology that enables a substantial

increment in the functionality and system performance. Though, the

technology is not new and has been used in high tech aerospace and military

applications, since 1980s.


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In recent times, the technology has only recently become a commercially viable

solution.

Embedded Passives


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Embedded passives are passive components (like resistor, capacitor, etc.)

buried into the substrate material. The IPC document “IPC-2316 – Design Guide

for Embedded Passive Devices Printed Circuit Board” provides necessary

information for incorporating embedded passive components in the PCB.

Embedding resistor with the circuit board uses “thin file” (subtractive process)

and “thick file” (additive process).

Thin file technology uses bi-metal alloy film like NiP, NiCr or NiCrAlSi, which is

deposited on the copper foil. The copper and nickel are then etched to create

nickel resistors with copper terminations. The technology offers limited

resistance range: 25 to 250 ohm/square.


CHAIRMAN

Thick film technology uses polymer thick films which are printed either

directly on the etched copper terminations or on screened silver plate

terminations. Interposing screened polymer silver paste between the copper

and resistor results in highly reliable and stable resistor. As multiple

materials can be printed on the same layer, thick film technology offers wide

resistance range: 20 ohm to 10 Mohm.

Embedded capacitors uses planar embedded capacitor laminates. These high

dielectric laminates are used to create planer capacitor layers which are

accessed using VIAs. New smaller packages discrete passive component also

known as embed discrete which can be buried in the PCB materials adds new

possibility with the embedded component technology.


CHAIRMAN

The advantage of using embedded passives components are:

- Improved system performance: Improved signal integrity, reduced EMI and

reduce parasitic.

- Achieve higher active circuit density and board yield.

- Reduction in circuit board size and weight.

- Reduction in assembly cost.

Embedded Actives

Embedded actives refer to the technology of embedding active devices into

the circuit board. It is most commonly found in integrated circuit packaging.

As integrated chips are turning into chip-sets, 3D packaging of the integrated

circuits is quite common.


CHAIRMAN

Embedding ICs within the circuit board may vary based on the following

approaches:

1) Embedded wafer level package

2) Embedded Chip Buildup

3) Chip in polymer

Substrate materials

Glass fiber / epoxy prepregs have dominated the PCB market for decades. FR-4

has become the standard substrate for PCBs, which uses only woven fiberglass

and epoxy. Traditional printed circuit board (PCB) laminate materials have their

limitations to support these high-speed and RF/Microwave applications. The

demand for higher frequency and faster data transmission rates has been

rapidly increasing.


CHAIRMAN

New substrate materials like Resin Coated Copper (RCC) / Resin Coated Film (RCF), Liquid

Crystal Polymer (LCP), and vacuum-laminated films have been introduced. PCB laminate

manufacturers like ROGERS, ISOLA, ARLON, ITEQ are offering high performance – low and

ultra-low dielectric loss (Df < 0.007) and cost effective solutions with the rapidly changing

electronics market.

Following image represents the performance v/s cost comparison of the few substrates in

the market.


CHAIRMANCategory Relative Cost wrt.

FR4 substrate

Tier 1 1x

Tier 2 1x

Tier 3 1x

Tier 4 1.5x

Tier 5 3x


CHAIRMAN

Creating your next embedded carrier board

Toradex computer-on-modules make use of the latest PCB technology to create

high performance embedded computer modules. Toradex’s embedded

computing solutions (system-on-modules and carrier boards) takes advantage of

both HDI technology and industry standard multilayer technology. This unique

combination enables our customers to create next generation embedded

solutions at a very low cost.

Accelerated development and reduced design risks: In order to speed up your development time and reduce the development risk associated with custom carrier board development, Toradex provides reference designs of our carrier boards in electronic format.

https://www.toradex.com/computer-on-modules


https://www.toradex.com/products


https://www.toradex.com/products/carrier-boards-for-system-computer-on-module



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These reference designs include all schematics, layout, and IPC-7351 compliant

component libraries in Altium designer format. By reusing hardware subsystems

already deployed on our off-the-shelf carrier board solutions, you can ensure that

you are starting with a design which works and has been designed to specifically

support Toradex’s computer-on-modules.

Toradex Carrier Board Design Guide helps circuit designers to gain better understanding of the embedded computer module solution offered by Toradex and other interfaces in-order to create a custom carrier board.

The Toradex Pinout Designer is a powerful tool for configuring the pin muxing of the Colibri and Apalis modules. The tool allows comparing the interfaces of different Toradex modules. It's easy to check whether existing carrier boards are compatible with the latest Toradex modules.



http://developer.toradex.com/hardware-resources/arm-family/carrier-board-design

https://www.toradex.com/products

http://developer.toradex.com/knowledge-base/pinout-designer

https://www.toradex.com/computer-on-modules/colibri-arm-family

https://www.toradex.com/computer-on-modules/apalis-arm-family


CHAIRMAN

Custom carrier board design often includes high speed interfaces like PCIe, SATA, USB, Ethernet, etc. Toradex layout design guide provides a wealth of very valuable technical information to help you with designing your own custom carrier board. Important information regarding circuit design and layout helps ensure that you get your design right first time.

Manufacturing: Updated Bill of material for Toradex carrier boards is available on the Ciiva BOM management tool. Ciiva provides a fully traceable, version-controlled BOM management.

Generating 3D design data: Toradex PCB footprint libraries include accurate 3D

step models for most of the components. During design phase, it helps provide

designers the provision to inspect the carrier board in 3D view. It allows PCB

design engineers to work in collaboration with the industrial design team. 3D-

step models can output of the custom carrier can be generated and can be

shared with the industrial engineering team and vise-versa.




CHAIRMAN

Please refer the below for more information;

http://developer.toradex.com/hardware-resources/arm-family/carrier-board-design

www.developer.toradex.com

www.toradex.com

|www.toradex.com Toradex® is a registered trademark of Montadex GmbH 12/1/2015 23

Thank

you!

technological trends in the field of circuit board design and manufacturing

Documents

global pcb market

global pcb demand

pcb geometries

technology rigid

european pcb industry

standard multilayer

manufacturing technology

chairmanhdi technology