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.
All Different Types of HDI PCB Grow Your Projects
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. 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 surface. Micro vias are used to build up the layer.
The 2step 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 materials such as uniform glass, which has a low dielectric constant.
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.
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 an HDI 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.
Related HDI PCB Boards
HDI PCB Production Details As Following Up
We’re capable of manufacturing HDI PCB up to 30 layers in various structures, please check our HDI PCB capabilities by reviewing the table found below:
|Min Board Thickness||0.35mm (13.78mil)||0.3mm(11.8mil)|
|Max Board Thickness||4.2mm (250mil)||6mm (236mil)|
|Min Initial Copper Foil Weight||1/3 oz||1/3 oz|
|Min Mech Drill Diameter||0.2mm (7.87mil)||0.15mm (5.9mil)|
|Min Laser Drill Diameter||0.1mm (4mil)||0.1mm (4mil)|
|Min Finished Hole Size||0.1mm (4mil)||0.1mm (4mil)|
|Blind Via Finished Hole Size||0.1mm (4mil)||0 (Fully Plated shut)|
|Buried Via Finished Hole Size||0.1mm (4mil)||0.1mm (4mil)|
|Minimum Trace Width/Spacing||3mil/3mil||2.75mil/2.75mil|
|Min Pad Size for E-test||6mil||6mil|
|Minimum Wire Bond Pad size||> 6mil||5mil|
|Controlled Impedance Tolerance||+/-5%, +/-10%||+/-5%, +/-10%|
|Solder Mask Registration||+/-2mil||+/-2mil|
|Solder Mask Min Dam Size||0.1mm (4mil)||0.1mm (4mil)|
|Min Diameter Rout Cutter Available||0.6mm (24mil)||0.6mm (24mil)|
|Laser Hole Location Tolerance||0.5mil||0.5mil|
|Thickness Tolerance||10% (as per stack-up)||< 10% (as per stack-up)|
|Sequential Lamination||3 or fewer lamination cycles||> 3 lamination cycles|
|Buried Vias||2 or less||> 3|
|Conductive Filled Vias||Yes||Yes|
|Non-Conductive Filled Vias||Yes||Yes|
|Aspect Ratio||-10:1(HASL Lead-free, HASL Lead, ENIG, Immersion Tin, Immersion silver, ENEPIG);||-10:1(HASL Lead-free, HASL Lead, ENIG, Immersion Tin, Immersion silver, ENEPIG);|
|Flash Gold (Electroplated Gold)||Yes||Yes|
|Flash Gold (Electroplated Gold)+Gold finger||Yes||Yes|
|Immersion Silver+Gold Finger||Yes||Yes|
|Immersion Tin+Gold finger||Yes||Yes|
|V-Cut, Edge to Copper||0.25mm (9.8mil)||0.25mm (9.8mil)|
1, Why Should I Turn To HDI?
At some level of circuit complexity, turning to architecture with blind and buried vias will result in better yield and lower cost than would a through-hole design. In this presentation, we discuss several design examples and illustrate the relative costs and benefits of different architectural approaches.
2, What Is The Standard Delivery Time For HDI Boards?
We can produce the prototype of HDI boards with 1-2 weeks for standard leading time, 3-4 weeks for mass production of HDI PCBs.
3, What Is A Microvia Hole?
A micro via is a blind structure with a maximum aspect ratio of 1:1, terminating on a target land with a total depth of no more than 0.25mm measured from the structure’s capture land foil to the target land.
4, What Is Meant By A Blind Via Hole?
It is a hole that runs from an outer layer to the inner layer, but not through the entire PCB. These holes can be drilled mechanically or using laser technology.
5, What Is Meant By A Buried Via Hole?
This is a hole that runs between one or more inner layers. They are normally mechanically drilled.
6, How Do I Select Materials For HDI?
Materials play a large role in terms of manufacturability and the direct cost of your circuit board. Here is a tip: The goal is always to select the right material for manufacturability that, at the same time, meets your temperature, and your electrical requirements. When it comes to materials, make sure that your high-speed material is also suitable for your HDI design. They are many other factors that come into play when selecting the proper materials for your design. Use our free Material Selector to find out which materials will suit your application the best.
7, Is There Any Minimum Order Quantity For HDI Boards?
No, we can produce 1 to 10,000 pieces, what’s more, there is also no minimum order surcharge or additional fees
Your Qualified HDI PCB Manufacturer.
Are you looking for an HDI 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 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 of HDI 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’ high-quality HDI PCBs. We also ensure to deliver the product within the scheduled delivery time.
If you have any HDI PCB demand, PCBMay is your best supplier. When you have some questions or inquiries with regard to the HDI PCB product, please send an email to us immediately.
HDI PCB: The Ultimate FAQ Guide
HDI PCB is a high-density interconnection technology, which is one of the technologies used by printed circuit boards.
HDI is mainly produced by the technology of micro-blind buried vias.
The characteristic is to make the electronic circuit distribution in the printed circuit board have a higher circuit density, and due to the large increase in circuit density.
It also makes the printed circuit board made of HDI unable to use ordinary drilling.
The hole formation method requires a non-mechanical drilling process for HDI.
There are many non-mechanical drilling methods, among which “laser hole formation” is the main hole formation solution of HDI high-density interconnection technology.
- What is HDI PCB
- Through Holes and Micro-Holes in HDI PCB
- What is the Function of Blind Holes in HDI PCB?
- Basic Types of Blind Holes in HDI PCB
- So, Here are the Four Main Types of Blind Holes in HDI PCB:
- How to Make Cheap HDI PCB?
- How to Design HDI PCB on Allergo?
- Role of Coupon in Production of HDI PCB
- The Reliability of HDI PCBs
- Major Applications of HDI PCB
- Structure of Several Different HDI PCB Types
- HDI PCB Board Design Guidelines
- Improvement of Wiring Density by HDI PCB
- Why HDI PCB?
What is HDI PCB
PCB products are diversified. From the perspective of output value distribution, PCBs are mainly four types of products with the largest proportions of soft boards, multilayer boards, HDI, and IC substrates.
The reliability of HDI PCB is directly affected by the quality of the copper connections and the base material.
Copper compounds are tested on a special test sample – coupon, by cyclic thermal effects, using a special method – the IST (Interconnect Stress the Test).
HDI PCB (High-Density Interconnect) is a high-density interconnection technology, which is one of the technologies used by printed circuit boards. HDI is mainly produced by the technology of micro-blind buried vias.
The characteristic is to make the electronic circuit distribution in the printed circuit board have a higher circuit density and due to the large increase in circuit density.
It also makes the HDI PCB unable to use ordinary drilling. The hole formation method requires a non-mechanical drilling process for HDI.
There are many non-mechanical drilling methods, among which” laser hole formation” is the main hole formation solution of HDI high-density interconnection technology.
Through Holes and Micro-Holes in HDI PCB
In the process of designing a printed circuit board, the developer sometimes faces the need to make blind holes – that is, transitions from one layer to another, without drilling the printed circuit board through. This may be due to various reasons:
- A complex component with a small pin pitch, such as a BGA with a pitch of 0.5 mm or less.
- Too tight routing with a small PCB, and the need to create additional routing “channels” in the area under the via.
- The need to eliminate that piece of the via that is not involved in the electrical contact between layers (the so-called stub), so as not to create unnecessary problems for high-speed signals.
- The need to limit signal propagation to only a few layers, with shielding of the remaining layers – for example, when separating the analog and digital parts of the circuit.
What is the Function of Blind Holes in HDI PCB?
To designate such holes, the terms blind via are used (the hole goes to only one of the outer layers), buried via (the hole is completely inside the board, connecting two or more inner layers), micro via, or via (the hole is made by a laser between two adjacent layers).
In general, the blind holes in HDI PCB technology, which implies a high density of connections, very small gaps and width of the conductor on the board, and the use of blind holes, is collectively called HDI PCB (High-Density Interconnect, or “high density interconnects”).
There are several international standards related to HDI boards, their design, production, and quality control, for example:
HDI Cross Section
The terms “blind holes”, “buried holes”, “micro-holes”, etc. are used, while these terms, as far as I understand, are not always understood in the same way by different specialists.
Basic Types of Blind Holes in HDI PCB
When forming blind holes, when describing them in CAD of printed circuit boards, it would be nice to understand in advance what technology will be used by the manufacturing plant to create them.
In this article, we will describe several basic types of blind holes. We will use the example of making a 4-layer PCB with a blind hole between layers 1 and 2.
Moreover, we will also give recommendations on their use in your projects, including the case of using high-frequency materials and prepregs, such as the Rogers 4000 series.
The information is based on the recommendations of various foreign manufacturers of printed circuit boards, with which the PCBMAY company – manufacturer of printed circuit boards “PCB technology”.
Based on this information, you will be able to create more complex designs in the future by combining these types of holes and these technologies.
So, Here are the Four Main Types of Blind Holes in HDI PCB:
1. Stack up + HDI (extrusion with foil on the outside plus micro-holes)
2. Core + Core + HDI (core plus core plus micro-holes)
3. Drill + Resin flow (drilling plus resin flow)
4. Drill + Resin plug (drilling plus resin driving)
Let us describe these options in more detail, having considered the sequence of the main operations for their manufacture, and give recommendations for the design of such boards.
How to Make Cheap HDI PCB?
The fewer press cycles and the fewer types of vias, the cheaper your board will be.
On average, each additional type of blind vias can add 20 to 50% to the cost of ordering a PCB.
Note that at the same time, the presence of such holes can allow you to reduce the total number of layers in the board, lower design standards, and reduce the overall dimensions of the board.
And often, as is the case with BGA components with a pitch of 0.5 mm, blind holes cannot be dispensed with at all.
Support for Blind Holes in CAD
It should be noted that modern CAD systems support blind hole technology quite well.
For example, in CAD Cadence Allegro and its OrCAD subset, it is possible to create a pad stack for a given pair of layers in one click, simply based on the through-pad stack you have selected in the design.
In the process of routing, the user can choose from which layer to which he needs a transition, and at the same time indicate which type of blind holes existing in the project to select for this operation.
When generating design documentation and Gerber CAD files, it automatically generates the required set of drilling files.
How to Design HDI PCB on Allergo?
In addition, Allegro has a special option, the Allegro PCB Miniaturization Option, designed specifically for working with HDI boards, and allowing you to work not just with individual micro-holes, but with their ladder and stack structures as “topology objects”.
In this case, the object “structure of micro-holes” can be not only placed on the board but also modified to meet the requirements of a particular situation.
For example, stepped micro-holes connected into a single structure in layers 1-2, 2-3, and 3-4 can be the way the developer needs.
It is oriented in topology to simplify routing. Also, the Allegro Miniaturization option allows you to fulfill all the necessary technological requirements (DFM – design for manufacturing, “development for production”) to ensure the possibility of efficient design and high-quality production of printed circuit boards from the very first iteration.
Support in CAM systems
Modern CAM systems used to inspect HDI PCB manufacturing files do a good job of supporting blind holes.
For example, the Gerber file editor CAM350 version 14 allows, at the time of loading Gerber and NC-drill files, to conveniently sort them and indicate between which pairs of layers certain blind holes should be located, and specify the type of micro-holes.
Moreover, the CAM350 offers to automatically retrieve the connection table based on the layer and hole topology.
If you have the ability to extract a similar netlist from your CAD, you can use the CAM350 to check the resulting Gerber files for correctness and compliance with this netlist.
Role of Coupon in Production of HDI PCB
The coupon is manufactured in the same product and has the same characteristics as the corresponding printed circuit boards: the same design, copper weight characteristics, hole sizes, mesh sizes, and copper plating.
The coupon goes through at least 500 heat cycles or until it suffers damage, leading to an increase in resistance of at least 10%, which occurs due to the formation of microcracks in the copper coupon joints due to thermal effects.
Possible damage to the base material is determined by measuring the capacity between the coupon layers before and after testing.
The measurement results are compared. A change in the capacity of 4% or more indicates significant material damage.
The Reliability of HDI PCBs
The loss of reliability of HDI PCB boards is primarily due to the use of lead-free assembly technology.
It is produced at a temperature of about 260 ° C, while the FR-4 material has a limited temperature range.
Thermal expansion of the material along the vertical component at such temperatures causes stress “tension” of copper joints.
As a result, it leads to microcracks in the central zone through metalized holes.
If the board remains operational after 500 thermal cycles when tested up to 150 ° C, the test sample is considered as a reliable coupon, that is passed the IST.
The reliability of HDI PCB boards is also determined by the type of design.
A circuit with micro-holes stacked on top of each other is almost four times more “sensitive” to failure than a design with the same staggered structures. Well-made one- or two-layer micro-holes have virtually no early failures.
Boards with three or more micro-holes located one above the other are more likely to fail IST at 190 ° C and, accordingly, will have production problems.
HDI boards have the following distinctive characteristics:
- Thinner gaps and conductors, namely ≤75 μm
- Reduced vias (micro-holes) ≤100 μm
- Small via pads ≤260 μm
- The high density of placement of contact pads, more than 20 per cm2
- Special dielectric materials
- Sequential lamination
The main advantage of HDI PCB is the ability to fit a huge number of different elements on a small board.
Major Applications of HDI PCB
HDI boards are used in:
- Mobile communication devices
- Portable electronic devices
- Complex medical devices
- Video surveillance systems,
- Aviation devices.
Structure of Several Different HDI PCB Types
- HDI type 1: Vias and microvias.The number of layers varies and depends on the ratio of the vias and the thickness of the FR-4 dielectric, which can delaminate at very high temperatures.
- HDI Type 2: Here are micro vias used and buried vias. These vias are covered by additional layers after drilling. Micro vias can be used next to or above the buried vias. The number of layers is limited with this HDI type.
The difference between HDI type 2 and HDI type 3 is that there are at least two micros via layers on one side of the circuit board.
Micro vias can be placed directly over the hidden burrows. This HDI PCB board is suitable for very large and densely populated circuit boards with several BGA packages with many pins.
HDI PCB Board Design Guidelines
Minimize the number of hole types exiting the same layer or useless precision conductors and gaps in such a layer.
In general, it is possible to advise the developer, before designing the layer structure and creating new types of blind vias.
It is to work out the question of:
- How exactly HDI board will be manufactured?
- At which manufacturing plant;
- In what sequence are the cycles of pressing layers?
- Drilling and metalizing holes will be performed by filling holes with copper or resin, etc.
The fewer press cycles and the fewer types of vias, the cheaper your board will be. On average, each additional blind vias can add 20 to 50% to the cost of ordering a PCB.
Note: Note that at the same time, the presence of such holes can allow you to reduce the total number of layers in the board, lower design standards, and reduce the overall dimensions of the board.
And often, as is the case with BGA components with a pitch of 0.5 mm, blind holes cannot be dispensed with at all.
Improvement of Wiring Density by HDI PCB
The HDI PCB board is a build-up multi-layer PCB that uses a sequential stacking method developed from the need to interconnect packages with a large number of inputs and outputs.
It is characterized by using micro vias with a hole diameter of 0.15 mm or less and is an effective technology for mounting BGA devices with 1500 or more pins and 0.8 mm pin pitch.
When emphasizing thin and short consumer electronics, mobile devices, smartphones, and even wearable devices in recent years.
As for the rise of the Internet of Things (IoT), the use of FPC soft boards, HDI, and even Any Layer HDI high-density PCB; advanced PCB manufacturing process Brings a very high technical threshold and yield test.
Moreover, it also drives equipment suppliers to update and evolve from laminating machines, screen printers, drilling machines to AOI equipment…
Why HDI PCB?
The volume requirements of products are getting higher and higher, especially the size of mobile device products is developing in the direction of continuous shrinking.
For example, the current popular Ultra Book products, and even novel wearable smart devices, must be made with HDI high-density interconnection technology.
The carrier board, which further reduces the size of the terminal design.