IC is some of the essential components of almost every technology, so they continue to undergo extensive growth. Do you happen to be working in the electronics industry? If so, then you must comprehend the importance of IC packaging. With efficient IC packaging, you get to achieve a lot. You protect your electronic products, such as PCBs, from corrosion or physical damage.
By going through this article, you’ll understand more about the importance of IC packaging. Better yet, you’ll get to understand several types of IC packaging and which one suits you the most.
(An IC on an isolated white background)
1. What is IC packaging?
IC is the material containing a semiconductor device. If you open your printed circuit board, you’ll see them. On the other hand, the package is a case surrounding the circuit material to protect them, especially from corrosion. It also gives room for easy mounting of electronic contacts on a PCB.
In the manufacture of ICs, the packaging is of high importance, though it comes last in the process. Therefore, IC packaging is the encasement whose aim is to shield electrical components from physical damage and corrosion. It also assists in holding leads and contact pins that connect a device from external circuits.
2. What are the types of IC packaging?
Two types of IC packaging are mostly standard. They depend on their manner of mounting on a printed circuit board. They are:
2.1 Through-hole mounting package
The design of the through-hole mounting package is simple. Here, you mount the lead pins through a single side of the board and solder on the other part. They find heavy use in electronic equipment as a means of compensating for a board’s cost limitations and space. Under through-hole mounting, we find the following types of packages:
DIP package ：
These are some of the most heavily relied upon IC packages. If you are keen enough, you’ll notice that the pins are parallel to each other. They also extended somewhat perpendicularly and laid out on some black plastic housing. The housing is rectangular in most cases. Based on the size and the difference in the PIN, the package sizes will vary. Mostly, the numbers range from 4 to 64. There are several types of DIP Packages. However, Molded Dual In-Line Package (MDIP) and Plastic Dual In-Line Package (PDIP) are the most common.
Standard is another type of through-hole mounting package. If you didn’t know, Standard is the most common and popular type of IC packaging. Many PCB assemblers and those in the electronics industry rely on this type of packaging. The spacing of the pins here is at 0.1 inches apart. The space between the terminal rows in this type of packaging is 7.62mm.
Shrink is also another popular through-hole integrated circuit mounting package. Even though shrinks are quite similar to standard ones, the lead pitch is 1.778 mm. They are a bit smaller and tend to employ high pin density packaging.
Zigzag (ZIP) in linear package ：
The insertion of pins in this type of packaging is perpendicular to the circuit board. The alignment of pins in the package is vertical and tends to sit close to each other. Zigzag linear packaging wasn’t that popular across the electronics industry. Zigzag goes down in history as a short-lived technology that mostly saw its heavy use in dynamic RAM chips. Today, not so many electronics makers even think of using it anymore as IC packages. Most of them rely on DIP Package, Standard, and Shrink Packaging.
2.1.1 Surface mount packaging
Surface mount packaging is the technology that involves picking and placing components on a bare PCB. While this fabrication process is quite fast, on the other side, it may come with its defects. Defects may arise due to the miniaturization of components, which is common in this type of technology.
When you place parts close to each other, it becomes impossible to detect defects. Nevertheless, it’s a form of IC packaging. Manufacturers can achieve surface mount IC packaging in two ways, as explained below:
Small size L-shaped lead package -This type of packaging consists of gull-wing type leads. These leads tend to draw out correctly in either direction in an L fashion from the body. Manufacturers can easily mount them on the board based on their simple rectangular shapes with horizontal edges. These types of packages are prevalent in integrated circuits used to power flash memories and RAM.
Ball grid array (BGA) -A ball grid array or BGA, in short, is a chip that carries a surface-mount package mostly seen in computers. But unlike other IC packages where a perimeter can connect, the entire bottom surface is easily mountable on BGA. Based on shorter ball connections, you’ll notice that BGAs offer ICs some of the highest speeds. Ball Grid Arrays are other types of IC packages that use plastic molds.
2.2 Classification of IC packages by structure
Based on formation, there are a variety of ways where we can categorize IC packages. There are two common types of IC packages: lead frame type and substrate type. Lead frame packaging finds heavy use in almost all IC packaging. In lead frame packaging, the frame consists of a thin copper layer. Of importance to note is in this type of packaging, one size doesn’t always fit all. More than often, customers ask for customized lead frames. All this depends on the size of the ICs on the printed circuit board.
Besides the lead frame type, there’s the substrate type packaging of ICs on a circuit board. Here a package substrate finds use in packing the core ICs. Lead frame IC packaging ensures the transmission of electric signals between the ICs and the circuit board. This type of packaging is ideal as it shields expensive semiconductors from instances of external stress.
Apart from the basic lead frame and substrate type IC packaging, there are other ones worth noting. The following are some of them:
Pin grid array is an integrated circuit packaging standard that finds heavy applicability in many second – through fifth-gen processors. Socketing relies on them the most, with the array packages being either square or rectangular. Pin grid is ideal for processors consisting of larger-width data buses since they can correctly handle the needed number of connections. This type of integrated circuit packaging comes with a few advantages. For instance, there are plenty of pins per integrated circuit and cheaper than BGA.
Square flat packaging (Lead-free lead frame packaging)
As long as ICs existed, so is leaded packaging. This packaging type is easy to identify as they spot a semiconductor die with IC’s rest of plastic mold encapsulation. Here, the metal leads do surround the perimeter of the package. Also, the name square flat packaging is one of the most heavily used package types. Most PCB makers use this type of IC packaging when manufacturing their boards.
Quad Flat No-lead
Finally, yet importantly, is the Quad Flat No-lead IC packaging. It is a tiny or rather miniature IC packaging. This type of packaging depends typically on the chip’s size and most common in surface mounting. Mostly, sizable integrated circuit boards rely on this type of packaging. However, you need to know that Surface Mount Device (SMD) technology heavily applies here. Quad Flat No-Lead packing is low cost and ideal for high-frequency use. Still, it’s relatively easy to operate them and very high when it comes to matters concerning reliability.
(A through-hole IC)
3. Through-hole Mounting VS Surface Mounting
As noted earlier, two types of IC packaging are common: through-hole mounting and surface mounting. The following are notable areas of comparisons between the two.
Through-hole mounting a package requires large components. If you compare the sizes of ICs on plated-through hole PCBs and those under SMT, you’ll notice a big difference. SMT allows for smaller PCB size, meaning that the ICs here are small and compact, unlike in plated through-hole. If you are concerned about size when packaging your ICs, your better choice is surface mount over through-hole. Since the surface mount is small, it means that you can save on space also.
Component density ：
surface mounts IC packaging results in high component density, unlike through-hole packaging. With surface mount, it’s possible to fit everything in a much smaller space while achieving functionality. That’s not the case when it comes to through-hole, where components tend to be too large. As an example, several 14 or 16-pin dual in-line processors that measure around 0.80 inches x 0.35 inches can perfectly fit in an area of one square inch or smaller. But on the other hand, such would be impossible would it have been plated through-hole packaging.
Assembly error correction：
At some point, errors are prone to occur regardless of the type of technology employed. When errors occur, correction or repairs may be necessary. When looking at error correction, you can undertake such quite fast with plated through-hole packages. The components are large enough for visibility and ease of repair. But such isn’t always the case with SMT. Since the parts tend to be small and sit close to each other, error correction becomes a tricky affair.
Electromagnetic compatibility is the ability of electronic components to work as desired. They should do so in their electromagnetic environment. There’s better electromagnetic compatibility in SMT compared to through-hole. The reason for such is that SMT offers a shorter return path. The quicker return path comes about since components sit close to each other as opposed to through-hole.
With through-hole, there’s some significant cost-saving, unlike SMT. For instance, packaging using through-hole doesn’t require the use of detailed and expensive equipment. This type of mounting may end up saving circuit makers hundreds of thousands of dollars. But when it comes to surface mount, the manufacturing costs tend to be slightly higher. For instance, manufacturers have to utilize a pick-and-place machine, one of the most expensive markets.
(A surface-mounted PCB)
4. Integrated Circuit Packaging Material
Electronic packaging is one of the most materials-intensive applications lately. Manufacturers need to use several materials here.
Types of materials：
The types of materials here include semiconductors, glasses, ceramics, composites, metals, and polymers. Glasses and ceramics work as insulators or dielectrics, while polymers work as conductors. Metals, on the other hand, work as conductors in the package. Composites contain a mix of materials that can work as electrical conductors or thermal enhancements.
The patch material：
The patch material is what you will have to use to make patches should you find yourself in such a situation. A patch is a piece of fabric that covers an undesirable opening. Plenty of patch materials that you can use exist. During IC packaging, you can use several of them. However, some of the ideal material is a piezoelectric material.
Lastly, when it comes to IC packaging, you may often hear of a sealant. But what are bonds and some of their uses? Just as the name goes, an adhesive is a material that individuals use to seal anything they want to close. The primary function of sealants is to ensure that the sealing devices are either watertight or airtight.
During IC packaging, sealants are necessary since they ensure that water or air doesn’t damage the IC’s rest. For these reasons, bonds are mandatory. Silicone sealant comes in as one of the ideal types of adhesives to use. They are long-lasting and perfect at protecting the whole package from cases of corrosion.
(IC packaging materials)
5. Assembly method of IC packaging
IC assembly electronically connects the output and input bond pads found on the IC to the corresponding bond pads on the package. In our case, the box is a system-level printed circuit board. There are several types of IC packaging that manufacturers use. Some of the most common ones include the following:
Dual-in-line package ：
Dual-in-line package or just DIP, in short, is one of the most common assembly methods of IC packaging. A dual in-line package is an electronic device package consisting of a rectangular housing. It has two adjacent parallel rows of electrical connecting pins. Take note that the box could either be through-hole-mounted to the PCB or just inserted in a socket. If you are keen enough, you’ll realize that most people refer DIP to DIPn. Here, n refers to the total number of pins. For example, a microcircuit package with two rows consisting of eight vertical leads would be a DIP18.
Small outline package ：
A small outline package is another IC packing assembly method that manufacturers use to achieve IC packaging, especially if they are small. The small outline package is slightly narrower and shorter than DIPs. The side-to-side pitch is 6 mm, while the body width is 3.9 mm. However, you need to be aware that the dimensions differ depending on the package in question.
Ball grid array ：
The Ball grid arrays use various assemblies to provide packages from 250 to 1089 input and outputs. It’s also one of the most common IC assembly methods.
Quad Flat Package ：
The Quad Flat Package is an IC assembly method that many manufacturers use. The reason for its heavy use is that it enables for one big reason. It allows SMD ICs consisting of high interconnections to find easy use in electronic circuits. Quad flat pack integrated circuits are in several formats with pins that vary in number.
(A Dual-in-line IC packaging)
6. How Should we Choose the Type of IC Packaging?
Before proceeding, we need to stress the importance of good packaging. Integrated circuits must stay in a package to ensure smooth handling and assembly on the PCBs. Choosing the right package is essential, as you’ll avoid cases of damage and corrosion. So, how do you go about choosing the right type of IC packaging? Continue reading to understand.
- The number of I/Os-First, the number of I/Os matters when choosing the package. Here, BGAs are the best for their high pin counts. But if you are on the market for a lower pin count, then the QFN package will be ideal for you.
- Heat management-Secondly, you need to consider matters to do with heat management. Today, the sizes of the ICs tend to be smaller but with more extensive capabilities. As such, they’ll most likely produce too much heat, a reason as to why heat management matters. BGAs tend to display effective heat dissipation, which is why you may want to go for them.
- High speeds I/Os-Third, when choosing your IC packaging, look at matters such as High-Speed I/Os. At any time, you do not want to interfere with the package’s quality to interconnect the IC I / O signals. For the best high-frequency signals, consider flip BGA.
- PCB assembly-Lastly, PCB assembly matters. Can you have the assembly of your IC package within the shortest time possible? Ensure that you factor in this factor beforehand as not every provider can offer you what you want.
(A correctly assemble IC chip)
7. Uses and advantages of IC packaging
IC play several essential roles in nearly all electronic circuits. They carry the entire processing of data and calculations. IC is also some of the most critical elements of storing data. Without ICs, an electronic circuit (such as a PCB) won’t function as intended.
IC packaging comes with several notable merits. For instance, IC packaging ensures the protection of the component from damage and corrosion. It also provides that there’s an adequate flow of current throughout the entire system.
IC packaging is also beneficial, with the package acting as a mechanism of “spreading apart” the connections from the tight pitch on the IC die. The box spreads these mechanisms to broad pitch areas that most PCB manufacturers require.
(Properly packaged ICs)
As you’ve seen, there’s much to IC packaging for electronics systems than you may think you know. Players, both old and new in the electronics world, need to get a clear picture of them. This way, it’s possible to stay abreast of new developments here.
Do you have questions concerning the various types of IC packaging or anything relating to PCBs? Feel free to contact us. We take pride in providing our clients with the information they need to make informed electronic parts decisions for their businesses.