Interposer PCB

Venture Electronics offers custom designed interposer board and adapter solutions for a wide range of applications.

They are most used as an interface to adapt obsolete components to an “old” circuit board that cannot be redesigned or is impractical to redesign.

But now due to global shortage of ICs, more and more customers choose to use easy to buy ICs to replace long lead time or hard to get ICs, at the same time without modifying your board design.

By developing a customized interposer board to “translate,” the circuit functions from one IC’s to the “old” application and package footprint.

In addition, this allows the customer to add features & functions not contained in the original design by incorporating them onto the new adapter or interposer PCB board.

Interposer PCBs are substrates which are used to attach components as an intermediate step to directly attaching to your mainboard PCB.

The interposer PCB board then becomes the new package for attaching onto the printed circuit board.

The substrate can be produced from a wide range of materials, including FR4, Polyimide, Rogers.

Printed circuit boards (PCBs) are mainstays in several devices and appliances we use today. Therefore, it is very relevant and comes in different variants.

But today, we will be looking at an essential variant of the PCB, which we call interposer PCB.

So we will be providing answers to several questions involving the interposer PCB.

What Is An Interposer PCB?

Interposer PCBs are PCBs whose circuit comprises interposers. This means that manufacturers use interposers in making the printed circuit board.

Interposer boards are underlying layers that act as an interface between components and the mainboard.

First, manufacturers attach components to the interposers, forming a sort of package. Then, the manufacturer then attaches the package to the motherboard.

Interposer PCB

What Are The Types of Substrates In Relationship With The Interposer PCB?

People use the word substrate interchangeably with interposers. Substrates are materials that serve as a base or platform for other electronic components.

There are two main types of substrates on the basis of their mechanical characteristics.

Tape Substrate

These kinds of substrates are flexible and relatively thin. Polyimide is the root material for tape substrates.

As a result, they boost high temperature and strength. Let’s see an advantage of tape substrate.

As they perform their task, acting as a base for electronic components to be built upon, they are mobile.

Other advantages include;

• Best fit for cases where manufacturers need microvia features
• Very cost-effective compared to other substrates
• Lightweight and flexible

However, there are some drawbacks of tape substrate, so let’s see what they are;

• A poor coefficient of thermal expansion
• Although it is lightweight and flexible, they prove challenging in the PCB manufacturing process
• Prone to warping

Rigid Substrate

From its name, you will notice that this substrate is in no way near flexible. We can also call it a laminate substrate since it consists of a pile of laminates.

As opposed to tape substrates which consist of polyimide, the rigid substrate consists of several more materials: Bismaleimide-Triazine (BT) and FR4

• FR4: this is a glass-reinforced material having epoxy laminate. As a result of its components, it is fire-resistant, which is the reason for the tag “FR-4.” It boasts good mechanical strength and insulating quotient.
• Bismaleimide-Triazine (BT): this continues to be the leading choice when it comes to laminate materials. It has excellent insulation features, high glass transition temperature(Tg), and low dielectric constant.

It’s best also to note that, continuous advancement in technology influences the emergence of newer substrate materials.

What Are The Types Of Interposer Designs For Interposer PCB?

There are a few designs relevant to interposers. They include

• Ball Grid Array – Ball Grid Array Design
• Pin Grid Array- Pin Grid Array Design
• Ball Grid Array- Pin Grid Array Design
• Surface Mount Technology to Dual In-line Package
• Ball Grid Array to Quad Flat Package Design
• Quad Flat Package to Ball Grid Array Design
• Surface Mount Technology to Surface Mount Technology
• Coefficient of Thermal Expansion Matching
• Joint Test Action Group

What Are The Considerations For Interposer Design For An Interposer PCB?

How you go about the interposer design influences the efficiency and quality of the PCB.

So for best results, there are a few things to consider as you venture into designing the interposers.

Let’s see what these crucial factors are;

Design of Pad

Pads are vital for PCB. On the circuit board, there are uncovered areas that are usually metals. These areas serve as lead soldering points, and we call them pads.

From the explanation above, you will see that it’s worth considering. The first is to determine the type of pad design.

Is it the surface mount pads or through-hole pads?

Concerning the pad design, you should note the following;

• Use an aspect ratio with good resistance to the stress the plating process exerts
• For each PCB application, ensure to comply with the standards for insulation spacing and tolerance for the padding system
• The connection between vias and traces should be quality

Other points of consideration include;

• A good plan on how the connection will go. The connection should follow industry manufacturing standards.
• A contingency plan for multi-die support
• A suitable bump pattern must feature
• A good management plan for the collection of pads, which we call nets

What Are The Efficiency Tips For The Interposer PCB?

Of course, it is a big blow to manufacture an interposer PCB with low quality.

This will affect your company’s credibility or give a poor consumer experience as an end-user.

Sure, there are quick tips that can transform the interposer PCB manufacturing process into that with a great end product.

Let’s see the crucial ones.

• Give priority to optimal connection. Remember, you are going to use the input and output signals on both sides of the interposer. So ensure they are tight, in good patterns, and in good shape.
• Ensure proper signal distribution on the interposer
• Consider using Bismaleimide-Triazine (BT) in place of FR-4 for optimal performance
• Do not comprise the appropriate number of vias for the interposer. This will cover both blind and buried vias.
• Traces should remain in the smaller regions of the BGA pad.

Are There Flexible IC Interposers For An Interposer PCB?

Yes, there are flexible IC interposers. They are still interposers but this time more flexible.

Flexible interposers are products of tape substrates hence their flexibility.

Flexible IC Interposers

They still perform the duties of basic interposers but also add more benefits. For example, flexible IC interposers have a wider range of applications due to their flexibility.

What Materials Make Up The Interposer PCB?

The interposer PCB has its name because its board comprises interposers.

These are underlying layers that serve as a conduit between the board and other IC components.

The interposer PCB owes its performance to its constituent materials.   Now, let’s check out the materials.

Polyimide

For sure, this is a famous mention in the PCB industry. Hardly will you go through the PCB concept without referring to polyimide.

Polyimide consists of a double bond of 2 acyl groups with nitrogen from its chemistry background. However, it is also a high-level polymer belonging to the imide monomers class.

Why is polyimide suitable for interposer PCB?

The following are the reasons.

• Amazing resistance to chemical
• Optimal mechanical performance
• It resists radiation and other environmental elements
• It doesn’t wear out easily
• Suitable for a wide temperature range
• Superb compressive and tensile strength

Although polyimide seems to be the manufacturer’s first choice, its major downside is its high cost.

Rogers Material

This is material from the Rogers company. They are usually void of central glass fiber and are of a high-frequency ceramic base. In addition, Rogers materials are suitable for high-speed designs.

Let’s see a few of its features.

• Superb temperature stability
• Minimal water absorption
• High dielectric constant

FR-4

It’s an abbreviation for flame resistant-4. This is a glass-reinforced material having epoxy laminate. As a result of its components, it is fire-resistant. In addition, it boasts good mechanical strength and insulating quotient.

Other materials are Stablcor and Getek.

What Are The Benefits Of Interposer PCB?

On a basic, the printed board circuit (PCB) provides several industrial benefits as well as benefits to the end-users. The same feats transits to the interposer PCB.

The interposer PCB has the following benefits.

• Since it is portable and lightweight, the interposer PCB produces much smaller systems and appliances. In addition, unlike the regular PCB, interposers have smaller linewidth and space.
• In the case of PCBs having out of date components and can not be redesigned, the interposer helps to support its component
• Due to its Technology, interposer PCB increases the performance of equipment and appliances of application
• It promotes minimal power loss in appliances of application

By virtue of its material quality, it also provides the following in areas of application

• Durable appliances
• Cost-effectiveness

What Is A 2.5D Interposer For Interposer PCB?

The concepts of the 2.5D interposer launch us to the idea of packaging technology.

Have you heard about the word “interposer technology”? That’s another name for the 2.5D interposer.

2.5D interposer

It is a packaging pattern where manufacturers arrange numerous electronic devices side by side on the same underlying layer.

From basics, you can see the interposer as a house taking in electronic components and giving them a connection to the outside world.

The big question is, why the 2.5D interposer?

Well, assembling the components with the interposer started out with the basic 2D Technology, where each component has a separate package.

Let’s make it a bit practical; they are laid in sections and then connected with thin wires.

This brought a few limitations, but the 2.D interposer steps up the practice with the following benefits.

• It creates the possibility of integrating materials of different nature, parameters, and requirements into one unit.
• It uses lesser space since components are not packaged separately. As a result, you can have systems of smaller sizes.
• They create room for lesser power outages, hence saving power
• Possibility for seamless integration which prevents the redesigning of components
• 5D interposer creates a shorter distance between components than regular circuits. When there are shorter distances, signals travel more swiftly and result in better performance.

What Are The Types Of Interposers For Interposer PCB?

There are a variety of interposers that features printed circuit boards. Without wasting time, let’s see what they are;

Organic Interposers

They consist of organic elements, for example, epoxy resin. Organic interposers are the cheapest interposers around the industry,

However, despite their low cost, they have much-reduced performance. Their usage also bears huge limits because they have little resistance to high temperatures.

Silicon Interposers

They are the most popular and accepted interposers in terms of usage. From its name, you see that it has its root from silicon.

The silicon interposer is far from cheap due to its high cost. And have an operational frequency limit.

Silicon Bridges

It still has good potential for the future, acting as an alternative to the silicon interposer. Simply put, they are interposers without through-silicon vias (TSV).

This kind of interposer takes relevance in situations where there is a need for lower cost, and the number of chips is quite small.

The bridge suggests that the interposer boycotts internal connections but makes direct connections with the chips.

Glass Optical Interposers

These interposers consist of glass and run with photons rather than electrons. However, when we take a look at its operational concept, it is unarguable that they are challenging to manufacture.

Therefore glass optical interposers are tipped to be the highest performing interposers.

What Is 3DIC Technology In Terms Of Interposer PCB?

The 3DIC stands for Three-Dimensional Integrated Circuit. It is a technology that involves stacking silicon dies or wafers.

After which, they are connected vertically using a copper-copper connection or the famous through-silicon vias.

3DIC Technology

It is one dimension ahead of the 2D since it adds the extra Z direction in circuit design and packaging. With 3DIC, you can merge several IC units into one package.

The 3DIC holds the following benefits.

• It makes designs more flexible and creates opportunities for redesigning circuits
• Supports the emergence of smaller devices and appliances since it ensures components occupies less space
• It supports the production of devices with higher bandwidth
• This Technology reduces costs significantly
• It supports heterogeneous integration.
• Since it involves a shorter wire connection, there is less power consumption

What Is The Difference Between 2.5D And 3D Packaging In Terms Of Interposer PCB?

When we talk about interposers in relation to PCBs, there are mainstay technologies that we can’t neglect.

They include 2.5D and 3D integrated circuit technology. So it’s time we analyze how these three technologies differ.

2.5D Packaging

It is a packaging pattern where manufacturers arrange numerous electronic devices side by side on the same underlying layer.

From basics, you can see the interposer as a house taking in electronic components and giving them a connection to the outside world.

Some of its benefits include;

• They create room for lesser power outages, hence saving power
• 5D interposer creates a shorter distance between components than regular circuits. When there are shorter distances, signals travel more swiftly and result in better performance.
• It uses lesser space since components are not packaged separately. As a result, you can have systems of smaller sizes.
• It creates the possibility of integrating materials of different nature, parameters, and requirements into one unit.

3D Packaging

The 3DIC stands for Three-Dimensional Integrated Circuit. It is a technology that involves stacking silicon dies or wafers.

After which, they are connected vertically using a copper-copper connection or the famous through-silicon vias

Therefore the major difference between the 2.5D and 3D is that 3D has an extra dimension (Z) in its setup, connection, and stack-up.

What Are The Applications Of Interposer PCBs?

Just as every other PCB, the interposer PCB has varying applications in several industries. This is owing to its structure, material, and overall Technology.

Consumer Electronics: Several electronics for end-user today comprise interposer PCB. You can find them in television sets, washing machines, refrigerators, etc.,

Automobile: You find its application in several automobile chips and packages.

Medical devices: With the advancement in Technology, several devices feature in the medical industry. They include computed tomography, insulin pumps, pacemakers, etc.

Military: this includes an underwater navigation system, firearms, control tower system, radio communication system, etc.

Telecommunications: this includes routers, telecom towers, mobile phones, etc.

They also feature in several industrial equipment and machinery.

What Is A Power Interposer For Interposer PCB?

Recall that the interposer acts as a base for several electronic components. One of these components constitutes the power unit of the circuit.

Power Interposers

The power interposer is a substrate that makes up the power supply unit.

What Is PCle Interposer?

Pcle stands for peripherical component interconnect express. The Pcle interposer is an intermediate layer that links high-speed components.

What Is BGA Interposer In Terms Of Interposer PCB?

BGA stands for Ball Grid Array. From the background, it features integrated circuits as a surface mounting package.

BGA Interposers

So the BGA interposer is an interposer founded on the BGA design. BGA interposers mainly appear in circuits with tin/lead solder profiles. It is also primary for low-temperature boards.

See some advantages of BGA interposers.

• Ball Grid design fosters reliability in devices for applications in the telecommunication, military, medical, and automobile industry.
• Perfect for the transition of the BGA device. It makes the cost much lesser.
• It creates the possibility for customizable circuits.

Does the Global Interposer Market Hold Good Tidings For Interposer PCB?

The fact is , the interposer market is very lucrative and holds good prospects for the interposer PCB.

The market analysis for 2021 creates an atmosphere to estimate the potential trend till 2026.

There is an estimation that the interposer market will hit 639.2 million dollars come 2026. This portrays an estimated growth of 18% in just five years.

The products in this market include 2D interposers, organic interposers, 2.5D interposers, silicon interposers, 3D interposers, etc.

For all affordable and reliable interposer PCBs, contact us now.