How does PCB laser drilling work & what are the advantages of using it?

By | Date posted: | Last updated: March 1, 2022
pcb-laser-drilling

When it comes to establishing connections between different layers of a PCB or placement of components, the advantage of laser drilling cannot be overestimated. Laser drilling ensures accuracy even when you need to drill even small holes. It uses concentrated laser energy for PCB laser drilling a hole as opposed to mechanical drilling.

The growing importance of PCB laser drilling

The importance of laser drilling is increasing on account of the fact that the use of HDI technology for PCB designing necessitates the use of microvias. These microvias being small in size require extremely precise and controlled depth drilling. This level of precision is made possible with the use of lasers. The use of mechanical drilling isn’t possible in such cases on account of the following:

  • Mechanical drilling causes drill vibration.
  • It isn’t suitable for drilling holes that are less than 6 mil in diameter.
  • Mechanical drilling does not lend itself to precisely controlled depth drilling.
  • Mechanical drilling is also both expensive as well as a time-consuming process.
  • Mechanical drilling is an expensive, time-consuming process. In a milieu where quick go-to-market is an essential requirement, this does not bode too well.
  • Since mechanical drilling involves hand selection of proper tools, the process can be replete with manual errors. This can lead to costly restarts impacting the overall project cost and timelines.

Laser drilling, on the other hand, can drill holes as small as 2.5 to 3 mil vias on a thin glass reinforcement. Where there isn’t a reinforced dielectric, it is possible to drill 1-mil vias as well.

Advantages of PCB Laser Drilling

If one was to look at the major advantages of laser drilling, therefore, they include:

  • No drilling vibration – Since laser drilling is a non-contact process, it does not lead to any drilling vibration. There is also no damage induced to the material.
  • Accuracy – The big advantage with laser drilling is that it is possible to control the beam intensity, heat output as well as the duration of the laser beam. That it means precision and accuracy in the kind of holes, is a given!
  • High Aspect Ratio – With laser drilling, it is possible to offer a high aspect ratio. A typical microvia is known to have an aspect ratio of 0.75:1.
  • Multi-Tasking – It is also possible to use laser machines for processes such as welding and cutting.

Different Types of laser drilling

laser-drilling-pcb

Laser drilling is possible in several types: important among those being:

Single pulse/Shot laser drilling

This kind of drilling is one where both the source of laser as well as the work material is kept static and where a single shot of laser beam is fired.

Percussion laser drilling

In this method, a series of laser pulses are shot. It works well in creating deeper and smaller holes.

Trepanning

In this process, a laser beam is guided around a predefined locus. It is particularly helpful where the diameter of the required via is larger than the diameter of the laser beam.

Helical laser drilling

In this method, the laser beam follows a helical path while rotating on its own axis.

Although laser drilling comes with a wide variety of advantages as detailed earlier, there are also some considerations that need to be kept in mind when using it.

Consideration for PCB Laser Drilling

Non-homogeneity of the stack-up

It is important to remember that different materials tend to absorb energies at different rates. It is, therefore, important that the PCB stack-up is kept homogenous as far as possible. With PCB materials that have varying optical and thermal properties, the reaction of the laser beams is also different. In turn, this leads to inaccurate drilling.

The thickness of copper

As a thumb rule, the thickness of the target copper layer should be twice the thickness of the top copper layer.

To Sum Up

As long as aspects such as the above are taken care of, laser drilling is indeed the best choice in creating microvias. With the increase of miniaturization as well as high density of wiring and components, the use of laser-drilled microvias is only slated to increase.

Technotronix is one of the leading PCB manufacturers based in the USA. We have adopted advanced methods and technologies, which can give you the finest PCB manufacturing services. We are adhering to strict high-quality standards and compliant with the RoHS (Restrictions of Hazardous Substance) directives. In case you have any questions, please feel free to contact us via email at [email protected] or call us on 714/630-9200.

The Significance of AS9100D Certification in Aerospace PCB Manufacturing!

By | Date posted: | Last updated: February 24, 2022
Aerospace PCB Manufacturing

When it comes to mission critical industries, printed circuit boards have to meet rigorous standards. The boards have to be high on reliability, low on maintenance and also have to perform under difficult environmental conditions.

It is for this reason that the AS9100D certification has been instated as a global aerospace manufacturing standard for the aerospace industry. It covers:

  • Aircraft component and materials manufacturers
  • Aircraft part and assembly designers
  • Quality management organizations and other companies that work with aerospace manufacturers

The certification ensures that certified PCB manufacturers and designers work relentlessly towards delivering highest quality PCBs.

What really is the AS9100D certification?

Released in 2009, this standard incorporates all the requirements of ISO 9001 requirements with additional industry specific requirements for aerospace and defense industries. In fact, most aerospace manufacturers and suppliers require compliance with AS9100 as a condition of doing business with them.

Broadly AS9100D focuses on 5 core processes in the aerospace industry, namely:

  • Quality Management Systems
  • Management Responsibilities
  • Resource Management
  • Product Realization
  • Measures of Improvement

By doing this, it ensures there is uniform compliance.
As far as the certification process for AS9100 goes, it is quite extensive and among other things involves:

  • 2 on-site audits
  • Various internal audits
  • Annual surveillance audits, and more

To obtain this certificate, electronics manufacturers have to follow a stringent list of standards over and above the basic ISO 9001 requirements. Not just that, contract manufacturer has to continue to fulfill the accepted standards year on year for renewals. Some of the standards that need to be fulfilled include:

  • Better configuration management than ISO9001
  • Risk management procedures
  • Industry-critical processes
  • Focus on timely delivery
  • Supplier approval process
  • Prevention of counterfeit components

Essentially, the goal of the certification is to demonstrate that the electronic contract manufacturing partner can offer products that meet statutory guidelines as well as customer requirements.

The AS9100D certification is contingent on the following aspects:

  • Product safety – This of course is the key consideration of the certification. Product safety needs to be demonstrated through the entire cycle of the PCB as also high-temperature applications.
  • Risk Based Thinking – Risk of course needs to be factored into all products including PCB boards. With rules around risk management becoming more stringent, proactive steps need to be taken to remain compliant.
  • Counterfeit Parts Prevention – The latest certification includes a whole lot of clauses that ensure that the use of fraudulent products is identified and stopped.
  • Human Factors – Under this certification, human failures are seen as a part of the failure of the system and it therefore offers an opportunity to improve the overall process.

Advantages of AS9100D certification in aerospace PCB manufacturing

With an AS9100D certification, you can rest assured that the contract manufacturer is committed to providing high-quality aerospace electronics PCB assembly & design. Some of the advantages offered include:

  • Customer Satisfaction – Whether you are looking at prototypes or full production runs, with an AS9100D certification you can be assured of complete satisfaction whether it is to do with PCN quality and its adherence to stringent quality standards or that the boards will be delivered on time.
  • Optimal Costs – With the AS9100D certification offering continuous improvement to the manufacturing operations, what it also brings is cost-effective price points.
  • Turnaround times – The processes so honed, offer quick turnaround times that make go-to-market that much easier.

Keeping up with AS9100 certification

Once electronics manufacturing companies earn the certification, they need to go through regular renewals. This ensures that they are complying with revisions if any. Recertification audits ensure that compliance is fully followed. While the recertification audit verifies compliance with all clauses of the standards, surveillance audits only review a sample of the clauses.

To sum up

With AS9100D Certification, you can rest assured that your Aerospace PCB Assembly will come with:

  • Improved product and process reliability
  • On-time delivery
  • Increased efficiency, reduced waste, better resource utilization
  • Improved bottom-line

Doing business with an AS9100D certified company will help you achieve a reliable product, better performance and efficient ways of working. Clearly then, the certification is the defining factor that stands between financial success and costly mistakes.

As an AS9100D certified PCB manufacturer, we combine state-of-the-art technology with our advanced engineering to deliver unparalleled quality aerospace PCB manufacturing services. With our four decades of experience, you can rest assured that we are cognizant of the industry’s best practices and will keep you ahead of the curve. Visit to know more about aerospace electronics PCB assembly & design or feel free to contact us. Also, you can drop an email to us at [email protected] or call us on 714/630-9200.

Challenges & top considerations to make your high-speed board design project successful!

By | Date posted: | Last updated: February 15, 2022
High-Speed Board Design

Two decades ago, if you spoke of high-speed data rate, you were in all probability referring to 3 Gbps. Today, of course, engineers can be dealing with as much as 25Gbps. While we are pushing for faster rates, we are also parallelly making smaller devices given the trend of miniaturization.

With high speed also come a number of challenges, primary among them being interference. In fact the faster the data rates, the harder it can get to protect the integrity of signals.

Making your high-speed board design project success, therefore, involves paying attention to a number of factors.

Here are some of the aspects to watch out for High-Speed Board Design:

Have a plan in place

This might sound like an obvious thing to do, but the fact remains that without a proper plan in place you are likely to suffer a whole lot of setbacks. The plan needs to include aspects such as:

  • Having a visual diagram for the sub-circuits and return current.
  • Knowing the frequency and fastest rise time of each signal.
  • Having a plan to meet requirements for differential signals, controlled impedance and more.
  • Documenting voltage and power requirements.

Document details of your board stackup

It is important to determine which material you will be using for the board and what are the specific constraints that need to be followed in terms of the design rules. FR4, for example, works well when you are working with speeds < 5Gbps. When it comes to between 5-25 Gbps clock speeds, Nelco, SI or Megtron work well. For high-speed designs, Rogers as a material is known to work well. Once the PCB material has been chosen, layer stackup strategies need to be kept in mind. Some of these include:

  • Placing a signal layer adjacent to a plane layer
  • Routing high-speed signals on the inner layers of the board
  • Using multiple ground planes to lower reference impedance.

Power and Ground Planes

The ground plane should not be split with any routed signals. Split it can lead to EMI and signal timing issues. In case a ground plane has to be split, a 0 Ohm resistor needs to be added.

Keeping size of land patterns minimum

With high-speed designs since the board real estate is at a premium, you need to save space. To this end, the minimum oversize of the pads should be kept at 0-5% of the size of the component pins. Also, the less the space given to vias, the more room there is for differential pairs, vias and more.

Route Signals for Maximum Shielding Benefits

To ensure that signals do not interfere with each other or with any component, some of the guidelines to be followed include:

  • Ensure you do not keep long, parallel signals
  • Maintain distance between signal traces
  • Route signals orthogonally

Path for Current Return

Using vias to return currents to their termination is recommended. Ensure also that the vias are impedance matched, differential vias. Return vias also need to be placed close to signal vias.

3W Rule

The 3W rule comes in handy to minimize coupling. The rule states that the separation between traces must be equal to three times the width of a single trace from center to center.

20H Rule

To prevent coupling between power and ground planes, it is advisable to sue the 20H rule. It states that the power plan must be made 20 times smaller than the dielectric thickness between adjacent power & ground planes.

General Routing Guidelines

When it comes to routing guidelines, the following tips will come in handy:

  • Avoiding 90-degree angle bends in your traces.
  • Length match tuning in the PCB design software is necessary.
  • Designing transmission lines with the use of microstrip or stripline traces is imperative.

To sum up

Overall arming yourself with strategies and knowledge to combat issues such as interference can go a long way in maintaining integrity of signals. Choosing the right electronics contract manufacturer who has the necessary experience, expertise and access to industry best practices is something that you must do in order to make your high-speed design successful.

We have over 4 decades of experience in providing innovative high-speed PCB design & manufacturing services. We take an extra step to reach out to your exact PCB manufacturing requirements, high-quality standards, and a strong customer support service to provide quick turnarounds and on-time delivery to our customers. In case you have any questions, please feel free to contact us via email at [email protected] or call us on 714/630-9200.

The Importance of FCT Testing in PCB Manufacturing & Assembly!

By | Date posted: | Last updated: January 24, 2022
FCT Testing

While it is important to stick to the highest quality standards in the process of PCB manufacturing, what is equally important is that you ensure that your board will operate as envisioned. This requires undertaking a set of tests at various stages namely prototyping, manufacturing as well as assembly.

PCB functional testing (FCT testing) comprises a whole range of tests that check for proper functioning of the board. Oftentimes, the manufacturer may also need to modify the PCB design for FCT in order to facilitate PCB functional testing. As long as the manufacturer understands your device’s functional requirements as well as your testing requirements, there will not be too many requirements for sending the design files back and forth. A cloud-based system for data access of course works best.

Let us look at PCB Functional Testing (FCT Testing) in some detail:

Simply put, PCB functional testing refers to a comprehensive testing regimen that determines that a manufactured board is ready to serve its purpose. The goal of PCB functional testing is to identify any defects that could impact its reliability. The defects could be by way of any missing components or as simple as any opens or shorts. PCB Functional testing, therefore, entails a wide variety of tests including but not limited to:

  • Visual Inspections
  • In-Circuit Tests
  • Flying Probe Tests
  • Bench Tests

Above everything else, PCB functional testing (FCT Testing) offers a comprehensive view of signal behavior. Some of the potent signal issues that can be identified through a PCB functional test include:

  • Power integrity issues: PCB functional testing can bring to light any issues such as jitter, low frequency noise, and more.
  • Signal distortion: Signal distortion, Skews and other such behavior can be identified through comprehensive functional testing.
  • Incorrect voltage: Incorrect Voltage can often be a result of a missing or incorrect component.

Comprehensive PCB functional testing involves building a custom test fixture. While this comes at a cost, with high volume manufacturing runs, the cost tends to quickly amortize itself, especially as it guarantees high quality

The Benefits of PCB Functional Testing (FCT Testing) Methods

  • Manual inspections – They are used to verify various aspects of the printed circuit board assembly process.
  • Automated Optical Inspection – It can be used to check issues such as:
    • Shorts
    • Any violations in spacing
    • Drilled hole breakout
    • Solder Paste Application
    • Location and orientation of components
  • X-Ray Inspection – X-Ray inspection can be used to examine components such as BGAs for solder defects.

Some of the systems that can undertake functional testing include:

  • Flying Probe Test: It can detect improper solder connections as also include some limited functional testing.
  • In-Circuit Test (ICT): This system works fast as also runs sophisticated functional tests. However, it isn’t used for low volume production as it is time-consuming and expensive.
  • CableScan: This relies on connectors as opposed to test points. It can search for assembly issues such as improper solder connections while also running functional test signals

Collaborating with the experienced PCB manufacturer

Collaborating early in the PCB design stage with the manufacturer is a great way to ensure the comprehensive testability of the board. With many PCB designs being put on hold before manufacturing, this is a great way to improve turnaround time. It’s important to check that the board complies with the manufacturer’s DFM recommendations and testing capabilities.

It is also important to evaluate that the PCB manufacturer offers the following services:

  • They have experienced test engineers that can develop hardware and software for functional testing, as also test fixtures and structures.
  • They have sophisticated testing equipment for a wide variety of testing such as flying probe tests, ICT and manual testing procedures.
  • They have existing relationships with component manufacturers.
  • They thoroughly document testing results.

To Sum Up

Clearly then, the abilities of the local electronics contract manufacturer are imperative to the success of the circuit board build. Done correctly, PCB functional testing is the most comprehensive testing regimen for determining whether a manufactured board is reliable for your purpose or not. Functional testing is integral to eliminating any errors that may crop up during the production phase, while also helping to reduce cost.

TechnoTronix is an ISO 9001:2015 certified company who delivers one-stop PCB manufacturing services with specialized support, reliable testing, and multi-functional features. Our consistent quality and quick turnaround time captivate us to our customers, who look on us as a one-stop-shop for all their PCB requirements.

If you have any requirements regarding our PCB manufacturing or need urgent assistance, contact us at [email protected] or call us on 714/630-9200.