Transitioning from Rigid to Flex / Rigid-Flex PCB Manufacturing

History of SEC

Peak of North American PCB Industry

Trough of North American PCB Industry m

illio

ns

year

Keys to Recovery

• Hold Production Quality Standards

• Pursue additional certifications

• Wide range of volume and technology

• (layers, materials, blind/buried, etc.)

• (proto through volume)

• Continued investment reduces cost by:

• Increasing operating efficiencies while reducing yield loss

Acquisition Details

• Formerly known as Proto Circuits, established 1978

• No investment since 1997 (or before)

• No sales force

• Few new customers within the last 10 years

• All certs dropped over time

Acquisition Challenges

• Customers designing around Proto’s weaknesses

• Loose systems

• Neglectful vendor base

• High cost structure

• Lack of management structure

Current Operating Results

• Attained profitability within 14 months

• Producing >10 layers rigid flex

• 2 mil line / spacing outer layers

• Complex blind / buried / sequential lamination builds

• In process of reinstating ISO9000 and Mil-Prf-31032

Ease of Transition

Dependent on Starting Point

• Standard 2-6 layer rigid shop?

• Blind / Buried; HDI; Advanced Technologies shop?

Identifying transferrable skills

• Drill development

• Tooling for multi-Lam registration

• Imaging Techniques

Myths

• Black Magic

• Materials difficult to handle

• Materials difficult to register

Truths

• Black Magic

• Materials difficult to handle

• Materials difficult to register

Truths

Black Magic = Experience and Learning

• Stackups

• Various flexible materials (adhesive vs. adhesiveless)

• Hybrid constructions

• Coverlay vs. Soldermask

• Sequential laminations

• Laminating with Cavity cutouts

Truths (cont.)

Materials difficult to handle

• 1 to 3 mil cores of flex material are commonplace

• Leaders are commonplace (increase labor content)

• Automation is very different than in rigid shops

Truths (cont.)

Materials difficult to register

• Standard rigid tooling systems no longer apply

• Multiple pins for each sequential lamination and drill cycle

Flex material has no grain

• Material behavior very different from FR-4

• Often expands rather than contracts

Change Management

Extract better parts of Rigid MFG system and apply to Flex

• Automation

• Quality Control verifications

• Sales / Service

• QTA offerings

Equipment

Standard Rigid Equipment can easily be used

• Slight re-tooling may be required

• Leaders for conveyorized processes

AOI and Testers

• Specialized for thin materials

All in all, not so much work needed here…

SO LONG AS YOU INVEST TIME TO ENGINEERING THE PROCESS

General Workforce

• Rigid shop machine operators simply operators

• Especially lower technology shops

• Subsequent inspection steps for filtering out bad parts

• With rigid-flex, however…

• No such thing as “just an operator”

General Workforce

Continuous Training should be required

• Engineering reviews for new part #’s

• Discussion of yield loss

• Root cause

• Potential actions that could have corrected for this

• Operators should be aware of selling prices and raw materials costs

• Dramatically higher than rigid prices and costs

Management

Rigid Shops (especially lower tech) tend to minimize costs via:

• Minimal Engineering

• Reduced training initiatives

• How to do the job vs. what the job means

• Throughput is paramount

Management, cont.

Demands of a Rigid-flex environment

MGT must provide financial/organizational support to the following:

• Continuous Process Engineering

• Promote Workmanship

• Sacrifice Throughput for better yield

Management, cont.

Continuous Process Engineering

• Tremendous amount of upfront engineering (establish that baseline)

• Drill Quality

• Lamination control

• Registration

• Adjust to changing designs / stackups

• Engineering on-the-fly is commonplace

Management, (cont.)

Promote Workmanship

Significantly increased training at the operator level

• Extra handling care

• Extra process setup verification

• More in-process testing

• Every operator needs to become an inspector

Management, cont.

Sacrifice Throughput for better yield

Rigid Production

• Based on number of panels per hour

Rigid-Flex

• Focused on number of perfect panels per hour

Management, cont.

Flex Customers are typically more scrutinizing

• Medical

• Military

• High-End Commercial

Flex’s scrupulous nature results in higher-reliability

Management, conclusion

Transitioning effectively from Rigid to

Rigid-Flex requires a commitment from

Management to absorb the educational

requirements necessary to not only

comprehending the Product but are also

vital to understanding Process Flows.