Your Reliable HDI PCB Manufacturer in China
PCBMay is a professional high density interconnect (HDI) PCB manufacturer in China with over 12 years of experience, we could offer many different types of HDI PCBs for you.
- Over 500 workers in the workshop
- Follow up your local working time and quote in time
- 7/24 sales and engineering tech support for your order
- 24h quick-turn service for your prototype of HDI PCB
PCBMay: Your Leading HDI PCB Supplier in China
As for your best partner for HDI PCB, we offer you a better solution for your HDI PCB design. Our CAM engineering department could provide some good suggestions when your project has some design problem so that it will save you some cost.
We offer different types of HDI PCBs such as 1+n+1, 2+n+2, 3+n+3, and any layer HDI PCB. PCBMay also offers a wide range of raw materials for your choice, including Shengyi, KB, NanYa, ITEQ, FR408, Rogers, Taconic, Arlon, and Nelco laminates.
We assure you to meet every detailed requirement of the Gerber file, if there is any design issue, we will inform you immediately via email prior to starting the manufacturing.
HDI PCB assembly is one of our areas of expertise. This information is provided to you so that you can learn more about our product offerings.
HDI PCB Series
The 1 step HDI PCB contains a single build-up of high-density interconnected layers, so it’s the most common form of HDI PCB. When constructing this PCB, it requires one sequential lamination on each side of the core. One build-up layer with a rigid core allows through vias from surface to emerge as a layer. Micro vias are used to build up the layer.
The 2 step HDI PCB has two HDI layers and allows micro vias to be staggered or stacked across layers. Complex designs usually incorporate copper-filled stacked micr ovia structures. One build-up layer with a rigid core allows through vias buried in the core and from surface to surface. This allows for variable depth micro vias or stacked micro vias.
The 3 step HDI PCB is that two or more build-up layers with a rigid core allow through vias buried in the core and from surface to surface. Stacked micro vias are used. For many PCB manufacturers, 1 step and 2 step HDI boards are easy and form the bulk of their HDI manufacturing business. 3 step HDI will also cost more.
The 4 step HDI PCB designs often require laser micro vias created with laser drills. These drills generate a laser at up to 20 microns in diameter, which can effortlessly cut through both metal and glass, creating very tiny but clean holes. You can get even smaller holes by using alternative materials.
This is a 12 layer with 5step high density interconnect(HDI) PCB, it needs better Laser Direct Imaging (LDI) technology, LDI is the go-to for fine lines and minute spacing because it can verify even the most demanding processes, continually expanding our capabilities and allowing for smaller form factors.
This is a 14 layer with 6step high density interconnect(HDI) board, Conventional core board laminating times are 3 times, this product needs to be laminated 6 times which is very complicated. The applications of this kind of HDI PCBs are automotive, aerospace, mobile communications, and medical devices, etc.
HDI PCB by Types (5)
HDI PCB by Shape & Size (5)
HDI PCB by Materials (5)
HDI PCB Advantages




PCBMay HDI PCB Properties
Our HDI manufacturing capacity allows us to fulfill any HDI PCB requirements you may have.
Low dielectric loss tangent or dissipation factor (Df)
Copper thickness 0.5oz to 10oz
Board type: Rigid and Rigid-flex
Board Thickness: Up to 10mm
Copper Thickness: Surface finish: ENIG, Lead-free HASL, OSP
Drill Hole Diameter: Mechanical (≥0.15mm) or laser (0.1mm)
We accommodate special requests too.


PCBMay HDI PCB Production
Advanced PCB fabrication technologies are used to create our quality HDI PCB.
We follow ISO 9000 and ISO 1400 standards, and we have Quality Control and Environmental Management Systems in place.
We employ the safest PCB manufacturing processes to ensure that your goods perform properly.
You can collaborate with our senior engineering team on your PCB.
We can assist you with circuit board design if necessary.
Even with a short lead-time, we can quickly produce custom-made HDI PCB. No hassle or delays.
PCBMay is a Custom HDI PCB Manufacturer for You
As a UL certificated PCB company, PCBMay manages the quality and assure to offer our customers high standard HDI PCB.
If you want to have a PCB supplier for your business, PCBMay is always here to support you.
PCBMay is an advanced HDI PCB supplier with over 12 years of experience and our customers are all around the world like the USA, Canada, Germany, UK, Spain, Italy, Israel, and so on.
The product applications are medical devices, aerospace, defense, military, industrial controls, LED lighting.
Your Qualified HDI PCB Manufacturer


Are you looking for a PCB supplier who could help you to solve all issues for your design? Good news! PCBMay proudly tells you that we are your best choice and perfect for all types of HDI PCBs for your demand.
For over 12 years in this industry, we have had full capabilities and a lot of experience with regard to PCB fabrication. Our HDI PCB will suit your requirement.
We have the quick turn service for the prototype PCB, therefore, when you need to produce HDI PCB as fast delivery, please send your Gerber data to us, we will provide a quotation with 1-2h.
As an ISO 9001 certificated factory, PCBMay strictly controls the quality of products and provides customers with high-quality HDI PCBs. We also ensure to deliver the product within the scheduled delivery time.
HDI PCB Fabrication
Our company’s mission statement includes taking good care of you as a customer.
The HDI PCB that we will send you will meet all of your industrial or personal PCB needs.
Advanced PCB fabrication technologies are used to create our quality HDI PCB.
We keep a close eye on Quality Control and Environmental Management Systems since we follow ISO 9000 and ISO 1400 standards.
Our HDI PCB is created using the most up-to-date PCB techniques available.
We practice strict Quality Assurance protocols.
We always follow international norms. We want to make certain that your order arrives in perfect condition.
Automated Optical Inspection (AOI), Flying Probe Testing, In-Circuit Testing, and Fixture Testing are some of the methods we use.
If you have any questions about PCB testing, just ask!
HDI PCB Applications
Our HDI PCB is used in power applications such as automotive power boards, electric car batteries, and power electronics.
For maximum durability, HDI PCB for Commercial Applications can be equipped with gold fingers. Automotive Dashboard is a good illustration of how it may be used.
Low-loss and high-speed functionality are required by HDI PCB for Computer Applications. It’s intended for usage in entertainment and communication devices.
Telecom, Mobile Phone, Backplane, and Cell Phone Module are all covered by HDI PCB for Telecomm applications. Immersion Gold is preferred as surface finish.
There is less radio frequency interference and electromagnetic wave interference on our HDI PCB for Medical Applications. This is why it’s popular.
HDI PCB Production Details As Following Up
- Production Facility
- PCB Capabilities
- PCB Materials
- Shipping Methods
- Payment Methods
- Send Us Inquiry
Item | Capability |
Layer Count | 1-40layers |
Base Material | KB、Shengyi、ShengyiSF305、FR408、FR408HR、IS410、FR406、GETEK、370HR、IT180A、Rogers4350B、Rogers4000、PTFE Laminates(Rogers series、Taconic series、Arlon series、Nelco series)、Rogers/Taconic/Arlon/Nelco laminate with FR-4 material(including partial Ro4350B hybrid laminating with FR-4) |
Board Type | Backplane、HDI、High multi-layer 、blind&buried PCB、Embedded Capacitance、Embedded resistance board 、Heavy copper power PCB、Backdrill. |
Board Thickness | 0.2-5.0mm |
Copper Thickness | Min. 1/2 OZ, Max. 10 OZ |
PTH Wall | 25um(1mil) |
Maximum Board Size | 1100*500mm(43”*19”) |
Min laser drilling size | 4mil |
Min. Spacing/Tracing | 2.7mil/2.7mil |
Solder Mask | Green, Black, Blue, Red, White, Yellow, Purple matte/glossy |
Surface Treatment | Flash gold(electroplated gold)、ENIG、Hard gold、Flash gold、HASL Lead-free 、OSP、ENEPIG、Soft gold、Immersion silver、Immersion Tin、ENIG+OSP, ENIG+Gold finger, Flash gold(electroplated gold)+Gold finger, Immersion silver+Gold finger, Immersion Tin+Gold finger. |
Min. Annular Ring | 3mil |
Aspect ratio | 10:1(HASL Lead-free 、HASL Lead、ENIG、Immersion Tin、Immersion silver、ENEPIG);8:1(OSP) |
Impedance control | ±5ohm(<50ohm), ±10%(≥50ohm) |
Other Techniques | Blind/Buried Via |
Gold Fingers | |
Press Fit | |
Via in Pad | |
Electrical Test |
Here there’re many laminate material datasheets, they’re useful and helpful for you, please see them:
SUPPLIER | PCB LAMINATE | TYPE | MATERIAL DATASHEET | TG | TD | DK(1MHZ) | DK(1GHZ) | DK(10GHZ) |
KB | KB-6160 | FR4 | DOWNLOAD | 135 | 305 | 4.35 | – | – |
KB-6160A | FR4 | DOWNLOAD | 135 | 305 | 4.35 | – | – | |
KB-6160C | FR4 | DOWNLOAD | 135 | 314 | 4.7 | – | – | |
KB-6150 KB-6150C | FR4 | DOWNLOAD | 132 | 305 | 4.6 | – | – | |
KB-6164 | FR4 | DOWNLOAD | 142 | 330 | 4.8 | – | – | |
KB-6164F | FR4 | DOWNLOAD | 145 | 340 | 4.8 | – | – | |
KB-6165F | FR4 | DOWNLOAD | 150 | 346 | 4.8 | – | – | |
KB-6167F | FR4 | DOWNLOAD | 170 | 349 | 4.8 | – | – | |
SHENGYI | S1141 | FR4 | DOWNLOAD | 135 | 310 | 4.6 | – | – |
S1141KF | FR4 | DOWNLOAD | 140 | 350 | 4.7 | – | – | |
S1000 | FR4 | DOWNLOAD | 155 | 335 | 4.9 | – | – | |
S1170 | FR4 | DOWNLOAD | 170 | 335 | 4.6 | – | – | |
S1000-2 | FR4 | DOWNLOAD | 170 | 335 | 4.8 | – | – | |
S1155 | FR4 | DOWNLOAD | 135 | 370 | 4.7 | – | – | |
ITEQ | IT-158 | FR4 | DOWNLOAD | 150 | 340 | 4.6-4.8 | – | – |
IT-180 | FR4 | DOWNLOAD | 180 | 350 | 4.5-4.7 | – | – | |
TUC | TU-768 | FR4 | DOWNLOAD | 180 | 350 | – | 4.3-4.4 | 4.3 |
TU-872 | Modified Epoxy | DOWNLOAD | 200 | 340 | – | 3.8-4.0 | 3.8 | |
ROGERS | RO 3003 | Cer/PTFE | DOWNLOAD | – | 500 | – | – | 3 |
RO 3010 | Cer/PTFE | DOWNLOAD | – | 500 | – | – | 10.2 | |
RO 4003 | Hydrocarbon/Cer | DOWNLOAD | >280 | 425 | – | – | 3.38 | |
RO 4350B | Hydrocarbon/Cer | DOWNLOAD | >280 | 390 | – | – | 3.48 | |
RT/duroid 5880 | PTFE/Glass | DOWNLOAD | – | 500 | – | – | 2.2 | |
ISOLA | Polyclad 370HR | FR4 | DOWNLOAD | 170 | 340 | 4.8-5.1 | – | – |
FR406-HR | FR4 | DOWNLOAD | 190 | 325 | 3.91 | 3.86 | 3.81 | |
FR408-HR | FR4 | DOWNLOAD | 200 | 360 | 3.72 | 3.69 | 3.65 | |
P96 | Polyimide | DOWNLOAD | 260 | 416 | – | 3.78 | 3.73 | |
Hitachi | MCL-BE- 67G | Modified Epoxy | DOWNLOAD | 140 | 340 | 4.9 | 4.4 | – |
MCL-E-679F | FR4 | DOWNLOAD | 170 | 350 | 4.2-4.4 | 4.3-4.5 | – | |
MCL-LX-67Y | Special Laminate | DOWNLOAD | 185-195 | 325-345 | – | 3.4-3.6 | – | |
Nelco | N4000-13 | Modified Epoxy | DOWNLOAD | 210-240 | 365 | – | 3.7 | 3.6 |
N4000-13EP | Modified Epoxy | DOWNLOAD | 210-240 | 350 | – | 3.4 | 3.2 | |
N4000-13SI | Modified Epoxy | DOWNLOAD | 210-240 | 350 | – | 3.4 | 3.2 | |
N4000-13EP SI | Modified Epoxy | DOWNLOAD | 210-240 | 350 | – | 3.4 | 3.2 | |
Taconic | TLX-6 | PTFE | DOWNLOAD | – | – | – | – | 2.65 |
TLX-7 | PTFE | DOWNLOAD | – | – | – | – | 2.6 | |
TLX-8 | PTFE | DOWNLOAD | – | – | – | – | 2.55 | |
TLX-9 | PTFE | DOWNLOAD | – | – | – | – | 2.45 | |
RF35 | PTFE | DOWNLOAD | <315 | – | 3.5 | – | 3.5 | |
TLC-27 | PTFE | DOWNLOAD | – | – | – | – | 2.75 | |
TLC-30 | PTFE | DOWNLOAD | – | – | – | – | 3 | |
TLC-32 | PTFE | DOWNLOAD | – | – | – | – | 3.2 | |
Arlon | Arlon 25N | Cer | DOWNLOAD | 260 | – | – | – | 3.38 |
Arlon 25FR | Cer | DOWNLOAD | 260 | – | – | – | 3.58 | |
Arlon 33N | Polymide | DOWNLOAD | >250 | 353 | 4 | – | – | |
Arlon 35N | Polymide | DOWNLOAD | >250 | 363 | 4.2 | – | – | |
Arlon 85N | Polymide | DOWNLOAD | 250 | 387 | 4.2 | – | – | |
Stablcor | ST325 | – | DOWNLOAD | Thermal conductivity:75w/m.k(with 1oz copper) | ||||
ST10 | – | DOWNLOAD | Thermal conductivity:325w/m.k(with 1oz copper) | |||||
Panasonic | R-1566W | FR4 | DOWNLOAD | 140 | 330 | 4.95 | 4.7 | 4.65 |
Ventec | VT-901 | Polymide | DOWNLOAD | 250 | 390 | 4.2-4.5 | 4.0-4.3 | – |
VT-90H | Polymide | DOWNLOAD | 250 | 390 | 4.2-4.5 | 4.0-4.3 | – | |
Bergquist | ht-04503 | – | DOWNLOAD | Thermal conductivity:2.2w/m.k(with 1oz copper) |
Delivery
PCBMay offers flexible shipping methods for our customers, you may choose from one of the methods below.
1. DHL
DHL offers international express services in over 220 countries.
DHL partners with PCBMay and offers very competitive rates to customers of PCBMay.
It normally takes 3-7 business days for the package to be delivered around the world.
2. UPS
UPS gets the facts and figures about the world’s largest package delivery company and one of the leading global providers of specialized transportation and logistics services.
It normally takes 3-7 business days to deliver a package to most of the addresses in the world.
3. TNT
TNT has 56,000 employees in 61 countries.
It takes 4-9 business days to deliver the packages to the hands
of our customers.
4. FedEx
FedEx offers delivery solutions for customers around the world.
It takes 4-7 business days to deliver the packages to the hands
of our customers.
5. Air, Sea/Air, and Sea
If your order is of large volume with PCBMay, you can also choose
to ship via air, sea/air combined, and sea when necessary.
Please contact your sales representative for shipping solutions.
Note: if you need others, please contact your sales representative for shipping solutions.
On our website you can use the following payment methods:
Telegraphic Transfer(TT): A telegraphic transfer (TT) is an electronic method of transferring funds utilized primarily for overseas wire transactions. It’s very convenient to transfer.
Bank/Wire transfer: To pay by wire transfer using your bank account, you need to visit your nearest bank branch with the wire transfer information. Your payment will be completed 3-5 business days after you have finished the money transfer.
Paypal: Pay easily, fast and secure with PayPal. many other credit and debit cards via PayPal.
Credit Card: You can pay with credit card: Visa, Visa Electron, MasterCard, Maestro.
Related Other PCBs
HDI PCB: The Ultimate FAQ Guide
The size of PCBs has been changing day by day. HDI PCB technology allows for the downsizing of printed circuit boards while simultaneously increasing wire and circuit density.
The demand for smaller and compact products with more performance and speed is vastly increasing day by day.
As a result, HDI technology brings such evolution in the PCB industry.
So, what about a broad discussion on HDI PCB?
Following this FAQ guide, you will be familiar with a number of fundamental facts concerning HDI PCBs. These might be helpful for you to give you a clear image of the PCB.
HDI is an abbreviation for High-Density Interconnect. It is a complex PCB design technology. HDI PCB technology enables the shrinking of printed circuit boards in the PCB sector. High performance and a larger density of wires and circuits are also provided by this technology.
By the way, the design of HDI circuit boards differs from that of ordinary printed circuit boards.
HDI PCBs Are More Complex Ones Than Traditional PCBs
HDI PCBs are powered by smaller vias, lines, and spaces. HDI PCBs are very lightweight, which goes hand in hand with their downsizing.
On the other hand, HDI features high-frequency transmission, control redundant radiation, and impedance control on PCB. The board density is high because of the miniaturization of the board.
Micro vias, blind and buried vias, high performance, thin materials, and tiny lines are all features of HDI printed circuit boards.
Engineers must have a thorough understanding of the design and HDI PCB manufacturing processes. The microchips on the HDI printed circuit boards need special attention throughout the assembly process, as well as superior soldering techniques.
The smaller sizes and weights fit the HDI PCBs in compact designs like portable computers, mobile phones, etc. Because of their smaller size, HDI PCBs are also less prone to cracks.
As we mentioned before, the HDI printed circuit boards are not the same as the typical PCBs, so you need to keep some facts while doing the HDI PCB design.
As a PCB designer, you should follow the following HDI PCB design guidelines.
Keep Space Priority In Mind
As the main objective of HDI PCBs is the density of the components, you must think about as many components as you can implement. Along with a lot of components, you must consider the future maintenance of the PCBs.
On the other hand, ensure the proper spacing among the components. Keep in mind that you must give importance to the via diameter, trace width, pad diameter for the flawless HDI PCB manufacturing process.
Understanding Via Essence
Vias are one of the most important factors in HDI PCB design. You must understand the via implication on your HDI circuit board design.
Understanding Via Is Essential for Designing HDI Circuit Boards
The vias play a vital role in making the HDI boards. They also affect the signal performance of the HDI printed circuit boards.
The uses of vias are different from through-holes.
Keep Solder Related Issues In Mind
To avoid shoddy connections, avoid the use of a via-in-pad. If not possible for valid reasons, then use a solder mask to cover the via-in-pad. Be careful while using a solder mask, as there are different complications of the solder mask itself.
HDI PCB Stackup
Select and implement the right HDI PCB stackup. Because the PCB stackup for the HDI multilayer PCBs impacts the drilling cycles.
The video below demonstrates how to incorporate HDI technology into printed circuit boards.
Vias are holes in PCBs that connect the different layers in the PCB electrically. Using multiple layers and connecting them using vias reduces the PCB size.
As the main goal of HDI circuit boards is to reduce their size, vias are one of the most important factors for them. Vias are available in different types.
Various Types Of Vias In PCB
Through-Hole Vias
It passes through the whole PCB, from its surface layer to its bottom layer, and is known as a through-hole via. By this point, they connect all of the layers of the printed circuit board. But, through-hole vias take more space and reduce space for components.
Blind Vias
Blinds vias just connect the external layers of the PCBs with the internal layers. No need to drill the entire PCBs.
Buried Vias
Buried vias are used to connect the internal layers of the PCBs. Buried vias are not visible from the outside of the PCBs.
Microvia
Microvia is the smallest via size less than 6 mils. You need to use laser drills for forming micro vias. So, basically, micro vias are used in HDI circuit boards.
It is because of its size. As you need component density and no way to waste space in HDI PCBs, it is wise to replace other common vias with micro vias. Also, micro vias don’t create thermal expansion issues (CTE) as they have short barrels.
Let’s see how to set up micro vias in PCB.
Depending on the design requirements and application, HDI PCBs are formed in different structures.
Let’s have a look at a quick illustration of the HDI PCB construction in the next section.
1+N+1: The Simplest Structure
A “build-up” high-density connectivity layer is included in the 1+N+1 construction. In this configuration, there are fewer I/O counts available in BGA.
Micro vias, tiny lines, and registration technologies are all found in 1+N+1. These can produce a 0.4-mm ball pitch. Furthermore, the mounting stability and reliability of this design are exceptional. It also has a copper-filled vial in it.
This HDI structure is used in cell phones, GPS devices, memory cards, and other devices.
2+N+2: Moderate Complex HDI Structure
Basically, there are at least two connecting layers in this architecture. More layers of build-up might also be employed. Micro vias are utilized in various PCB layers, and they may be stacked or staggered in their placement.
A 2-4-2 Construction Of High-Density Interconnect PCB
This structure is often utilized in the construction of high-level signal transmission systems. This unique structure facilitates the routing procedure in complex design situations.
By the way, this is particularly well suited for BGAs. Where the BGAs have tiny ball pitches and a high I/O count, the BGAs are superior.
This HDI structure is used by portable video recorders, mobile phones, and gaming consoles.
Every Layer Interconnection (ELIC): Most Complex HDI Structure
Every layer is powered by high-density interconnects in this topology. This also enables all layers to communicate with one another through micro vias.
It is the HDI design’s most complicated structure. This very complicated topology provides huge pin connectivity options for large pin-count devices. CPUs and GPUs, as well as cell phones, are examples.
This complicated HDI structure is used by GPUs, CPUs, cellphones, and computer gadgets.
As HDI printed circuit boards are designed with complex and highly advanced technology, high-end electronics use them.
The devices that use HDI circuit boards are highly complicated and generate excellent performance.
HDI Printed Circuit Boards Are Used In Varieties Of Applications
The following are the applications mentioned of HDI PCBs according to industries.
Consumer electronics: smartphones, touch screens, laptops, digital cameras, 4,5 G network communications, military communication system, etc.
Aerospace industries: use HDI circuit boards where decreased weight is a concern.
The automotive industry: is becoming more computerized and highly microprocessor-dependent. Smart cars are increasing the use of auto control, GPS, rear cameras, backup sensors, etc., through HDI PCBs.
Medical equipment: such as monitoring, imaging, surgical, laboratory devices, etc., are using HDI.
Industrial automation and IoT are becoming more popular. HDI PCBs are the common power providers of them.
HDI PCBs are capable of doing a lot with a little size. The fundamental objective is to make electronics smaller.
As a result, HDI circuit boards are compact, take up less space and perform better. HDI printed circuit boards enable the deployment of more transistors by reducing the distance between the trace space. In addition, HDI uses less electricity and provides better signal transmission.
HDI Circuit Boards Are Compact In Size And Lightweight
Aside from these, the following advantages are found using HDI PCBs.
- HDI is cost-effective when you properly plan and implement the design manufacturing.
- HDIs are advantageous with faster production.
- Micro vias are used in HDI printed circuit boards. they are reliable, dependable, less space-consuming, and allow more space for the components.
Base materials are used for HDI PCB in different categories. They are categorized as follows.
Regular Speed And Dielectric Loss Tangent
These types of materials are from the FR4 family. They are loss-prone to the dielectric. The regular speed materials are used in a particular range of bandwidth. Isola 70HR is an example of this material family.
FR4 Family Materials Are Used In Making HDI Printed Circuit Boards
Moderate Speed And Loss
Responsive frequency curves are a kind of material. Also, holds a moderate Dk level as well. Dk loss is half that of standard speed materials in this case. These materials are appropriate for frequencies up to 10 GHz. Nelco N700-2 HT is one of the examples of moderate speed and low loss materials.
High Speed, Low Loss
These types of materials are high-frequency based and lose low dielectric. The use of high-speed and low-loss materials results in a considerable reduction in noise. For example, Isola I-Speed material.
Large High Speed, Signal Integrity, And Deniable Loss
They are highly responsive to frequency, produce high frequency, and allow the lowest Dk loss. This high-end material is used for higher bandwidth. An example: ISOLA Tachyon 100G.
Laser Direct Imaging is the abbreviation for LDI. The HDI circuit boards portions, on the other hand, are processed using LDI and contact imaging.
LDI is more costly than contact imaging in this case. However, if you want a finer line, spacing, or annular ring, you’ll need a lot more control.
Laser Direct Imaging Is Perfect For Small-Sized PCB Processing
LDI is superior to contact imaging, yet contact imagery is still commonly utilized. In an SC100 room, contact imagery is employed.
The utilization of LDI is expanding day by day as long as demand and technology demand the latest innovation.
Because for the smaller-sized PCBs, LDI is extensively accurate. Electronics like smartphones, cameras, laptops are getting lightweight day by day because of HDI lightweight technology.
In this case, the need for cutting-edge and accurate technology like LDI is required for HDI processing.
Surface mount technology is a component placement technology on PCBs. It allows mounting components on the PCB without drilling the PCB for components.
As SMT components don’t need any drilling, they occupy smaller space. So, the components could be mounted in a compact space.
Surface Mount Technology Needs No Drilling For Component Placement
For this reason, SMT is used in higher-density designs like HDI.
There are many advantages of SMT technology. Theta er as follows.
- A smaller and compact PCB design is possible with SMT technology as you can mount more components in a compact space.
- SMT mounting process is faster and leaves fewer leads and leftovers.
- High-frequency PCB, fast signaling, etc., are created with SMT.
- You can mount the components on both sides of PCBs.
- SMT components create less electromagnetic interference.
- As the components are small and lightweight, the weight of the PCBs is reduced.
As we mentioned that the HDI circuit board is different from typical standard PCBs, you will face some challenges designing and manufacturing it. Let’s have a look at them.
Circuit Design
As might be assumed, the circuitry on HDI PCBs is more sophisticated than the circuitry on any other PCB type. The circuit has become denser, and the trace patterns have become closer to one another.
HDI Circuit Design Is Fairly Complex Than Standard PCBs
Drilling Holes (Vias)
Drilling holes are one of the most significant features of high-density interconnect (HDI) printed circuit boards. Because of the smaller and more compact design, it is not envisaged that typical holes will be present.
For HDI PCBs, you must utilize laser drilling or laser direct imaging as opposed to conventional methods.
Because conventional drilling will result in larger holes, which are not acceptable with HDI technology, traditional drilling is not recommended. In order to reduce the amount of wasted space in HDI, micro vias are used.
The length of the hole will rise in proportion to the increase in the number of layers. The maximum diameter of micro vias in HDI PCBs, on the other hand, is 50 µm.
While designing HDI printed circuit boards, you should consider some design facts in your mind. Since HDI is different from standard PCB design, it demands special consideration as expected.
Fill The Vias Holes In PCB
- Be precise for component selection. HDI boards need a high pin count SMD and BGA that is less than 0.65 mm. You need to select them wisely as they impact the via type, trace width, and HDI PCB stackup.
- You need to use micro vias in HDI boards. This will allow you to get double spaces than through-hole or other vias.
- It is necessary to use materials that are both effective and efficient. It is critical for the manufacturability of products.
- For getting a plain PCB surface, you should fill the vias’ holes.
- Try to select materials for all layers with the same CTE rate.
- Keep an eye on thermal management. Make sure you properly design and organize layers that can properly dissipate the excessive heat.
As an HDI board designer, you must know the following IPC standard for the HDI PCBs.
IPC-2315
HDI structures, as well as micro vias, are covered in detail in this chapter.
IPC-2226
High-definition interface (HDI) boards are described in detail in the IPC-2226 standard. These include the production of micro vias, the characterization of materials, the interconnection of structures, and so on.
IPC/JPCA-4104
IPC-4104 assists you in determining the kind of material used in HDI boards. This document also contains a description of the performance and qualification standard for the high-density structure of the printed circuit boards.
IPC-6016
This covers the features of the HDI materials that are consistent across time. Additionally, the performance and specifications of the HDI construction are described.
There are different types of HDI printed circuit boards in terms of layer counts, application, frequency ability, etc.
They are as follows.
HDI Multilayer PCB
Multi-layer reflects its name. There are at least three conductive layers that make a multilayer PCB. However, all layers are joint through vias in the PCB.
Multilayer PCB Stackup
The layer count could be 4,6,8, up to 40 layers, or more.
Rigid PCB
HDI PCBs are constructed from stiff materials, which are referred to as rigid PCBs. Rigid printed circuit boards (PCBs) are stiff and cannot be bent or twisted.
Flexible PCB
The PCBs that are made of flexible substrates are called flexible PCBs. High-grade flexible materials such as polyamide, TEFLON, etc are used in flexible circuit board design.
Rigid-Flex PCB
Rigid-flex printed circuit boards (PCBs) are a hybrid of rigid and flex PCBs. Essentially, a stiff board is joined to another flex board and then bonded together to make the fundamental shape.
The layout of an HDI circuit board ensures the component and wire density along with ensuring the smallest possible size of the PCB.
The layout of the HDI board means the techniques to keep the trace width under 8 mils. The HDI layout consists of the following things.
A Visual Representation Of HDI PCB Layout
Vias Sized Small
Basically, micro vias are used in HDI circuit boards. They consume smaller space that ensures more space for the component placement. The size of the PCB becomes compact due to this reason.
Traces with Thinner State
Connecting circuits and vias is accomplished by the use of finer traces. Additionally, they are available as in-pad vias. Thinner traces are responsible for creating increased trace density in the background.
Layer Count Remains Higher
The HDI PCB layout contains a higher layer count. Counting 20 layers is a normal fact in HDI boards.
Low Signal Level
HDI circuit boards are not used for higher current flowing applications. The lower signal level is another fact in the HDI circuit board layout.
The HDI board’s sequential stack-up aids in the layer-by-layer construction of the HDI PCB stackup. Although this technology is used to create multilayer printed circuit boards, it is especially important for high-density to interconnect (HDI) printed circuit boards.
The sequential buildup is as follows.
Photoresist Deposition and Exposure
You will be able to specify the etching region of the PCB using this procedure. It will result in a pattern of conductors on the PCB laminate as a consequence of this.
Etching and Cleaning
Etch the traces with ferric chloride to make them more visible. After the etching process is completed, clean the surface of the PCBs. ensure that no photoresist is left on the surface
Via formation and Drilling
Drill the board using a laser direct imaging method to add micro vias. The remaining via holes are then chemically removed.
Sequential Layer Stackup In HDI Circuit Board
Metallization Of Vias
After you have established and structured the vias, you must metalize them in order to allow connections between the layers to be made.
Stack-up
The inner layers are now stacked in preparation for the outer layer processing.
Metalization is the process of depositing a thin copper coating on a dielectric surface. The metalized dielectric surface is located inside the vias that are drilled into the PCB layers in order to link them together.
When sequential construction is being carried out, it is essential to guarantee that each layer is metalized to the highest possible standard.
Metalization Process In HDI Printed Circuit Board
As a side note, you should be careful about the cracking of the vias and internal body of the printed circuit boards.
However, four types of PCB metallization are there. They are conventional electroless and electroplating copper, conductive pastes, conventional conductive graphite, and fully and semi-additive electroless copper.
The HDI PCB stackup is the organizing of the layers one by one. The number of layers or stackup could be determined based on the needs. However, this could be 8 layers to 40 layers or more.
But the exact numbers of layers are dependent on the density of traces. The multilayer stackup helps you to reduce the PCB sizes. It also reduces the cost of manufacturing.
By the way, to determine the layer count of your HDI PCB, you need to determine the trace sizing, and nets per layer. After determining them, you can calculate your required layer stackup of your HDI circuit board.
It is true that HDI circuit design takes more effort due to its complexity. For this, you must choose the right HDI PCB manufacturer for manufacturing this complex PCB to be done.
Because of the intricate nature of the design, the maker must possess exceptional qualifications. When looking for a manufacturer, you should look for the following characteristics.
- To make HDI PCBs, a manufacturer must be equipped with cutting-edge technology and production capabilities.
- They must have a quality management system that is integrated across the organization.
- Must hold IPC certification.
- Must have extensive experience in the field.
- The office staff must be highly trained and skilled.
The mentioned criteria will make a manufacturer fit for manufacturing the complex HDI printed circuit boards.
HDI PCB manufacturing is one of the toughest and most complex tasks in PCB manufacturing. You must have extensive infrastructure and experience to design and manufacture HDI circuit boards.
As you gain a brief knowledge about HDI printed circuit boards, you may realize the toughness of designing them.
So, there is no alternative to a highly experienced and organized PCB manufacturer to select.
PCBMay is your one-stop PCB manufacturer that manufactures extensively qualitative HDI PCBs.
You may contact us for the best quote today.